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51.
The performance of a watermarking method based on Singular Value Decomposition (SVD) has been improved for color image in this paper. One of the common methods used for hiding information on image files is Singular Value Decomposition method which used in the frequency domain. In Singular Value Decomposition based watermarking techniques; watermark embedding can usually be achieved by modifying the least significant bits of the singular value matrix. This paper gives application results which show the watermarking security of using this algorithm for the watermarking and demonstrate the accuracy of these methods. The performance comparison of the algorithms was also realized.  相似文献   
52.
A microwave-enhanced advanced hydrogen peroxide oxidation process (MW/H2O2-AOP) was studied in order to investigate the synergetic effects of MW irradiation on H2O2 treated waste activated sludges (WAS) in terms of mineralization (permanent stabilization), sludge disintegration/solubilization, and subsequent anaerobic biodegradation as well as dewaterability after digestion. Thickened WAS sample pretreated with 1 g H2O2/g total solids (TS) lost 11-34% of its TS, total chemical oxygen demand (COD) and total biopolymers (humic acids, proteins and sugars) via advanced oxidation. In a temperature range of 60-120 °C, elevated MW temperatures (>80 °C) further increased the decomposition of H2O2 into OH radicals and enhanced both oxidation of COD and solubilization of particulate COD (>0.45 micron) of WAS indicating that a synergetic effect was observed when both H2O2 and MW treatments were combined. However, at all temperatures tested, MW/H2O2 treated samples had lower first-order mesophilic (33 ± 2 °C) biodegradation rate constants and ultimate (after 32 days of digestion) methane yields (mL per gram sample) compared to control and MW irradiated WAS samples, indicating that synergistically (MW/H2O2-AOP) generated soluble organics were slower to biodegrade or more refractory than those generated during MW irradiation.  相似文献   
53.
Methacrylate based side‐chain liquid crystalline polymers (SCLCP) bearing cholesterol pendant moieties with various lengths of aliphatic spacer were synthesized and their electrical conductivity mechanism was studied for their possible applications in elastic microelectronic devices. All the polymers exhibited liquid crystalline behavior of broken focal‐conic fan texture of smectic phase. The dielectric properties of polymers were investigated by impedance spectroscopic technique in the frequency range of 100 Hz to 15 MHz at room temperature. Alternating current (AC) conductivity ( ) of the liquid crystalline polymeric films was observed to vary with angular frequency, ω as ωS with s < 2. Detailed conductivity analysis revealed that the conductivity of the polymeric films follows quantum mechanical tunneling and correlated barrier hoping conductivity mechanisms at low frequency regime, whereas it obeys super linear power law and direct current conductivity mechanisms at high frequency region. The investigation of the SCLC polymeric films helped to propose a model system for their possible potential applications. In the light of this study, the SCLC polymers will be employed as the gate insulator for organic field effect transistor applications, such as large area flexible arrays or as other advanced microelectronic devices that have superior performance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45207.  相似文献   
54.
Using electronic-reverse auction (e-reverse auction) offers many advantages to companies such as price reduction, decrease in cycle time, standardization, and transparency in purchasing process. Despite its great advantages, some users do not want to use e-reverse auction technology for the procurement of products or services. This study aims to understand factors affecting e-reverse auction usage in companies by integrating three important theories. Key constructs of technology acceptance model (TAM), theory of planned behavior (TPB), and innovation diffusion theory (IDT) are integrated to explain behavioral intention to use and actual use of e-reverse auction. Using LISREL 8.54, data collected from 156 employees working in the procurement department of companies in 40 different countries were used to test the proposed research model. Results indicated that, 76% of employees’ intention to use e-reverse auction is explained by subjective norms, perceived behavioral control, and perceived usefulness. Among them, subjective norms have the strongest effect. Besides, actual use of e-reverse auction is directly predicted by behavioral intention to use. We conclude with managerial implications and recommendations for possible future research.  相似文献   
55.
High-efficiency air filtration is a basic requirement for the most cost-effective operation of high-efficiency gas turbines. The filtration system protects the gas turbine from damaging debris. In gas turbine/dust collector applications, higher efficiency filtration could be achieved with nanofibers, which provide higher equipment protection than traditional media. With a nanofiber performance filter layer, the dust accumulates on the surface of the filtration media rather than within the media and could be cleaned off easily with a back pulse resulting in long filter life and a low-operating pressure drop. In this study five type of gas tribune nanofiber coated corrugated cellulose/synthetic filter media were developed. Nanofiber coating was adjusted for five filtration efficiency level, 50 ≤ E < 60, 60 ≤ E < 70, 70 ≤ E < 85, 85 ≤ E < 95 and 95 ≤ E, pore size and filter-life of the developed media were evaluated. One of the developed nanofiber coated media was also compared with two other commercial nanofiber coated gas tribune filter media, a glass fiber type filter media and a commercial fine fiber gas tribune filter media. It was seen that, with decreasing penetration levels due to nanofiber coating level, initial 30 cycle durations of filter life evaluation could reach about 229.9 to 250.7 min. Highest final cycle duration of 188.7 min belonged to cellulose/synthetic blend corrugated filter media with penetration of 13.66%. Nanofiber based surface filter media was cleaned up better than fine fiber media and final 30 cycle sequences were significantly higher. Surface of the nanofiber coated media was smoother when compared to fine fiber media and during the initial and final cycle test dust could not penetrate inside and could not hang to this smooth surface. So, with back pulse cleaning cake releasing have performed easily. It was also seen that, for higher filter life nanofiber coating should be uniform and robust to back pulse cleaning.  相似文献   
56.
The aim was to investigate the antibacterial activity of various acids and adhesives with and without antibacterial components against Streptococcus mutans. The antibacterial activities of 35% phosphoric acid (Ultra-Etch), 37% phosphoric acid with benzalkonium chloride (Etch-37), adhesive with chlorhexidine (Peak Universal Bond) and without any agent (PQ1) were investigated by agar-diffusion test. The inhibition-zones were measured after 48 h of incubation. For the tooth-cavity model test; cylindrical cavities were prepared on occlusal dentin surfaces of human molars and divided into four groups (n = 10 cavity/group). Group 1: Ultra-Etch + Peak Universal Bond, Group 2: Ultra-Etch + PQ1, Group 3: Etch-37 + PQ1 were applied. The fourth group without any agent application served as control. The teeth were immersed in 5.8 × 106 cfu/ml of S. mutans solution to infect the cavities for 72 h before the application of the groups. After 72 h, dentin chips were collected from the cavity walls with burs for bacterial counting. Statistical analysis was performed by ANOVA, Bonferroni and Dunnett C tests (p < 0.05). Ultra-Etch and Etch-37 performed similar antibacterial activities in agar-diffusion test. Both acids showed better antibacterial activity compared to adhesives (p < 0.05). The antibacterial activity of PQ1 and Peak Universal Bond was observed to be inactivated by light-polymerization. According to the tooth-cavity model; Group I, II, and III demonstrated reduction in bacterial number and there was no significant difference between them. Antibacterial component additions in etchant and adhesive did not show superior antibacterial activity against S. mutans in both in vitro tests.  相似文献   
57.
We present a fully automatic multimodal emotion recognition system based on three novel peak frame selection approaches using the video channel. Selection of peak frames (i.e., apex frames) is an important preprocessing step for facial expression recognition as they contain the most relevant information for classification. Two of the three proposed peak frame selection methods (i.e., MAXDIST and DEND-CLUSTER) do not employ any training or prior learning. The third method proposed for peak frame selection (i.e., EIFS) is based on measuring the “distance” of the expressive face from the subspace of neutral facial expression, which requires a prior learning step to model the subspace of neutral face shapes. The audio and video modalities are fused at the decision level. The subject-independent audio-visual emotion recognition system has shown promising results on two databases in two different languages (eNTERFACE and BAUM-1a).  相似文献   
58.
A modified membrane capacitive deionization (MCDI) unit with additional flow channels in the anode and cathode chambers was used to study the performance of ammonium ion removal. The influences of operating parameters including initial ammonium concentration, flow rate and applied potential and the effect of flow in the anode and cathode chambers were investigated. Flow through the anode and cathode chambers significantly enhanced the electro-sorption efficiency. The electro-sorption of ammonium at 5 mL/min was about 65% greater than without flow.  相似文献   
59.
With the growing usage of the Internet, the demand for online health care information and advice as well as the number of health‐related Web sites are increasing. In case of online health information and advice, the user interface replaces face‐to‐face communication. To ensure that the users' needs are met, it is critical to balance functionality and usability in the design of the Web site. The present study seeks to identify the complex interrelationships among the various factors of usability and functionality concerning e‐health Web sites. Two Turkish e‐health Web sites were assessed for evaluation in this study. The findings show that the users of the health information Web sites give a higher priority to functionality and its factors, whereby the highest relative importance is on “services/facilities” and “personalization/categorization of information.” The most important usability factors related to the e‐health Web sites are “memorability” and “interaction.” © 2012 Wiley Periodicals, Inc.  相似文献   
60.
1 1. Current address for Cigdem Ataseven is Operations and Supply Chain Management Department, Monte Ahuja College of Business, Cleveland State University, Cleveland, OH 44114, USA. In theory, competition improves productivity and performance; trade liberalisation, which increases imports/exports, brings more competition. Using two large-scale survey responses from over 1000 manufacturers collected during two different time periods while US exports were growing in an environment of trade liberalisation, this study examines the effectiveness of technologies, over time, in manufacturing plants with varying export intensities. We find manufacturing technology use increases with exports and exporters report significant gains in plant performance over time. The study considers hard technologies (i.e. technologies involving capital-intensive equipment in manufacturing operations) and soft technologies (i.e. technologies involving planning and administrative components) to understand the distinct dynamic impact of the use of these technologies among plants exporting with varying intensities. Manufacturing plants are categorised into high, medium, and non-exporting based on the plant’s exports as a percent of total output. The results of this study indicates that exporters engage in more skilled use of these technologies than non-exporters. Further, exporters not only have higher skilled use of manufacturing technologies from non-exporters, but they also expand the scope of technologies that they skillfully employ in their operations. We find that over the course of liberalised trade regime, medium exporters get closer to high exporters in their skilled use of manufacturing technologies providing evidence of learning effect from exporting. Finally, higher skilled use of manufacturing technologies by high exporters translates into lower rejects and shorter lead times. However, non-exporters were not able to gain similar benefits from using manufacturing technologies.  相似文献   
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