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51.
Colour evolution and colour changes were analyzed from small specimens of three heat treated wood species using the CIE L*a*b* colour space. Upon heat exposure, the wood substance became darker of species; this was accompanied by a steady reduction in lightness. As treatment conditions (e.g., time and temperature) increase, various shades of yellow were favoured for the surface of red‐bud maple wood (Δb = 1.22–9.79). For European hophornbeam wood, increased times at elevated temperatures make a blue (?b) colour the better choice. The total colour difference (ΔE) of the surfaces of wood substrates appear to be well correlated with the treatment temperature and time. The FTIR spectra suggest that the level of modification was insufficient for removing the major cell wall constituents of the wood substrates. All heat‐treated samples showed much less stability against colour difference in outdoor conditions. For red‐bud maple, the greatest improvement was achieved for samples that were treated at 150°C for 2 h (ΔE = 3.12). However, heat‐treated oak wood hadmuch less stability of colour difference for treatment conditions of 150°C for 10 h. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010.  相似文献   
52.
In this study, the effects of cutting forces on the support of horizontal woodworking milling machine are examined during profile cutting process using both experimental and analytical approaches. The support modeled in 3D using SolidWorks software is a crucial component of the horizontal milling machine used to locate and fix the wood workpiece during the cutting process on the workbench. The effects of cutting forces on the support specimens are measured experimentally considering vibration and failure analyses. Analytical stresses and modal analyses of the support were also calculated using finite element-based analysis approach. Chatter vibration forces of the cutting tool which resulted from cutting forces in x-, y-, and z-directions were calculated analytically during the profile cutting process. The results showed that both cutting and chatter forces are highly effective on the support component failure of the woodworking milling machines.  相似文献   
53.
We present a simple strategy to prepare doxorubicin (DOX) containing hydrogen‐bonded films of poly(2‐isopropyl‐2‐oxazoline) (PIPOX) and tannic acid (TA) which release DOX in acidic conditions while releasing a minimal amount of DOX at physiological pH. Water soluble complexes of TA and DOX (TA ? DOX) were prepared prior to film construction. PIPOX and TA ? DOX were deposited at the surface at pH 6.5 using the layer‐by‐layer (LbL) technique. We found that multilayers released a minimal amount of DOX at physiological pH due to further ionization of TA with increasing pH and enhanced electrostatic interactions between TA and DOX. In contrast, pH‐induced release of DOX was observed in moderately acidic conditions due to protonation of TA as the acidity increased and electrostatic interactions between TA and DOX decreased. Moreover, we found that raising the temperature from 25 °C to 37.5 °C increased the amount of DOX released from the surface. This can be rationalized with the conformational changes within the multilayers correlated with the lower critical solution temperature behaviour of PIPOX and increased kinetic energy of DOX molecules. Considering the acidic nature of tumour tissues and important biological properties of PIPOX and TA, these multilayers are promising for pH‐ and temperature‐triggered release of DOX from surfaces. © 2017 Society of Chemical Industry  相似文献   
54.
Influences of thermal annealing on structural, optical and morphological properties of the tantalum pentoxide (Ta2O5) thin films were investigated and anti-reflective performances were discussed in detail. The Ta2O5 thin films were deposited onto Corning Glass (CG), Si, GaAs and Ge substrates by radio-frequency (RF) magnetron sputtering technique using Ta2O5 ceramic target. The obtained secondary ion mass spectroscopy (SIMS) analysis results showed that uniform Ta and O distribution have formed throughout depth of the films deposited on substrates. The X-Ray diffraction (XRD) results indicated that the annealed Ta2O5 thin films at 100, 200, 300 and 500?°C have exhibited amorphous (a-Ta2O5) characteristic. The increased temperature has resulted in increasing the surface roughness from 0.67 to 1.60?nm. The optical transmittance of the annealed thin films has increased from 70.85 to 80.32% with increasing temperature. Spectroscopic ellipsometer (SE) measurement results demonstrated that the increased temperature has increased the refractive index of the Ta2O5 thin film from 2.11 to 2.18. The Ta2O5 thin film has reduced the average optical reflectivity of the Si, GaAs and Ge substrates by 78, 55 and 70%, respectively. In addition, thermal annealing process has decreased the optical reflectivity of the film. The obtained experimental results showed that single-layer Ta2O5 thin films can be used as anti-reflective layer in optical and optoelectronic applications. The best optical transmittance and anti-reflective performance were obtained at the annealing temperature of 500?°C.  相似文献   
55.
This paper investigates the accuracy of an adaptive neuro-fuzzy computing technique in suspended sediment estimation. The monthly streamflow and suspended sediment data from two stations, Kuylus and Salur Koprusu, in Kizilirmak Basin in Turkey are used as case studies. The estimation results obtained by using the neuro-fuzzy technique are tested and compared with those of the artificial neural networks and sediment rating curves. Root mean squared errors, mean absolute errors and correlation coefficient statistics are used as comparing criteria for the evaluation of the models’ performances. The comparison results reveal that the neuro-fuzzy models can be employed successfully in monthly suspended sediment estimation.  相似文献   
56.
Introduction Severe nephrotic syndrome is associated with increased morbidity and mortality. Renal artery embolization (RAE) has been used in a number of renal diseases such as renal tumors, arteriovenous fistulas etc. However, data regarding benefits of RAE in patients with symptomatic severe proteinuria is limited. We decided to evaluate role of RAE in the setting of severe symptomatic nephrotic syndrome. Methods Eight patients who had undergone transcatheter renal artery embolization with polyvinyl alcohol (PVA) were included. Clinico‐demographic characteristics as well as baseline laboratory data including level of proteinuria, serum albumin, C‐reactive protein and LDL cholesterol levels were recorded for each patient. After RAE, outpatient clinic control laboratory values were also assessed. Findings All patients except one underwent bilateral RAE (four simultaneous or three sequential). Two patients experienced postembolization syndrome characterized by flank pain, fever, and leukocytosis, which was self‐limited and responded to analgesics in all patients. There was no technical complications associated with RAE procedure. All patients became anuric except one. Serum albumin levels increased and serum LDL‐cholesterol levels decreased considerably in treated patients. Discussion Renal artery embolization with the purpose of amelioration in nephrotic syndrome complications was effective and free of major technical complications in our patients.  相似文献   
57.
Stock trading is one of the key items in an economy and estimating its behavior and taking the best decision in it are among the most challenging issues. Solutions based on intelligent agent systems are proposed to cope with those challenges. Agents in a multiagent system (MAS) can share a common goal or they can pursue their own interests. That nature of MASs exactly fits the requirements of a free market economy. Although existing studies include noteworthy proposals on agent‐based market simulation and researchers discuss theoretical design issues of agent‐based stock exchange systems, unfortunately only a very few of the studies consider exact development and implementation of multiagent stock trading systems within the software engineering perspective and guides to the software engineers for constructing such software systems starting from scratch. To fill this gap, in this paper, we discuss the development of a multiagent‐based stock trading system by taking into consideration software design according to a well‐defined agent oriented software engineering methodology and implementation with a widely‐used MAS software development framework. Each participant in the system is first designed as belief–desire–intention agents with their facts, goals, and plans, and then belief–desire–intention reasoning and behavioral structure of the designed agents are implemented. Lessons learned during design and development within the software engineering perspective and evaluation of the implemented multiagent stock exchange system are also reported. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
58.
Cetin  Saime Sebnem  Efkere  Halil Ibrahim  Sertel  Tunc  Tataroglu  Adem  Ozcelik  Suleyman 《SILICON》2020,12(12):2879-2883
Silicon - The TiO2/SiO2 film being the dielectric layer was grown on the n-Si wafer using radio frequency (RF) magnetron sputtering. Thus, the Au/TiO2/SiO2/n-Si metal-oxide-semiconductor (MOS)...  相似文献   
59.
The paper examines the impact of development activities on water pollution in Malaysia. Hence, the main objective of this paper is not just to examine the trends of development-induced water pollution around the region of the country but to know where the problems are and the policy measures taken by the government. It evaluates the probable causative relationship between problems introduced due to technology employed in water pollution control and governmental policy measures. It examines the relationship between development indicators as sources of pollution and polluted rivers over a period of 12 years. The findings of the paper have shown that despite the policy enforcement actions against the identified sources of water pollution, all the three development indicators (chosen based on those identified sources) still accounted for high percentage of river pollution in Malaysia. The findings of the paper were used to identify the central fact of the location of the problem. Some crucial conclusions of where the problems likely to be, as reflected in the findings, are: (a) the issue of interactive-effects between pollutants that many policy-makers are not aware of. This is when policy measures concentrate only on one source of water pollution; (b) the enforcement strength and/or effectiveness of policy measures themselves; (c) financial constraints to invest in appropriate technology especially sewerage systems for controlling human source of water pollution in the country; as well as those confronting small polluting industries (d) finally, lack of cooperation between government and private business firms to comply with regulatory policies for water pollution control.  相似文献   
60.
We examine the performance of multimodal biometric authentication systems using state-of-the-art commercial off-the-shelf (COTS) fingerprint and face biometric systems on a population approaching 1,000 individuals. The majority of prior studies of multimodal biometrics have been limited to relatively low accuracy non-COTS systems and populations of a few hundred users. Our work is the first to demonstrate that multimodal fingerprint and face biometric systems can achieve significant accuracy gains over either biometric alone, even when using highly accurate COTS systems on a relatively large-scale population. In addition to examining well-known multimodal methods, we introduce new methods of normalization and fusion that further improve the accuracy.  相似文献   
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