Electronic behavior of native oxide films on Ti and TiN during 90-day immersion in electrolytes with different pH levels

This work presents the electronic behavior of Ti and TiN thin films when exposed to electrolytes with pH levels of 2,7 and 13 for 90 days.Staircase potentio-electrochemical impedance spectroscopy tests were performed on the 100-nm Ti and TiN monolithic films,and MottSchottky analysis of these tests was used to determine the films' semiconductive behavior and changes in the donor/acceptor density.In addition,the flat-band potential of each film's surface oxide was also characterized.No attempt was made to control oxide formation,and therefore,these tests reflected the native surfaces of these films.While the TiN films exhibited n-type semiconductivity in all electrolytes,the Ti films only showed n-type behavior in the acidic(pH=2) and neutral(pH=7) electrolytes.The semiconductivity of the Ti films transitioned to p-type during exposure to the basic electrolyte(pH=13) after reaching 60 days.Furthermore,there was a significant increase in the donor densities for both Ti and TiN films when immersed in the basic electrolyte relative to the acidic and neutral electrolytes.     

Polyethylene glycol as an epoxy modifier with extremely high toughening effect: Formation of nanoblend morphology

The brittle nature of epoxy polymers is one of their main drawbacks, preventing their widespread applications. In this research article, a new modifier with an extremely toughening effect on brittle epoxy was developed. It was found that introducing low‐molecular‐weight polyethylene glycol (PEG) in the low amounts (up to 10%) into epoxy matrix considerably improves the impact and fracture properties of epoxy thermosetting polymer without attenuating its tensile properties. Epoxy/PEG hybrid containing 10% PEG exhibited an impact strength of 56.3 kJ/m² which is 5.7 times greater than that of pristine epoxy. The fracture strength of 7.7 MPa m^1/2 with 540% increase compared to pure epoxy was also observed for the hybrid material. Morphological, chemical, and thermal properties of epoxy/PEG hybrid were studied using scanning electron microscopy, Fourier transform infrared spectrometry, and differential thermal analysis, respectively, to find out the basic reasons behind such a considerable improvement. A new morphology, consisting uniformly dispersed PEG nanoparticles in the epoxy matrix, was observed for the modified hybrid. This unique morphology for epoxy/PEG was named as nanoblend. The results showed that the formation of nanoblend morphology with strong interaction between epoxy and PEG in the blend structure is responsible for epoxy toughness. POLYM. ENG. SCI., 54:1833–1838, 2014. © 2013 Society of Plastics Engineers     

A novel proposal for all-optical compact and fast XOR/XNOR gate based on photonic crystal

In this paper, we aim to design an all-optical device, which can perform XOR and XNOR functions in a single structure. The proposed structure will be realized by cascading two nonlinear resonant rings. The functionality of the proposed structure is based on controlling the optical behaviour of optical rings via optical intensity. The final structure has one bias and two input control ports, along with two output ports. One port acts as an XOR and the other acts as an XNOR gate. The maximum delay times for the XOR and XNOR gates are 1.5 and 2.5?ps, respectively. Therefore, the working bit rates for the XOR and XNOR gates are 666 and 400?Gbit/s, respectively.     

A new multi-level trust management framework (MLTM) for solving the invalidity and sparse problems of user feedback ratings in cloud environments

Choosing a trusted cloud service provider (CSP) is a major challenge for cloud users (CUs) in the cloud environment, as many CSPs offer cloud services (CSs) with the same functionality. Trust evaluation of CSPs is often based on information from quality of service (QoS) monitoring and CUs’ feedback ratings. Despite the volume of feedback ratings received in trust management systems, the quality of feedback storage is very low, as many CUs do not send their feedback ratings when using CSs. Additionally, a percentage of existing feedback ratings may not be valid, since some malicious CUs send unfair feedback ratings to change the trust evaluation results. As these lead to poor data quality, the accuracy of trust evaluation results might be affected. To overcome these limitations, this paper proposes a new multi-level trust management framework, which completes previous frameworks by defining new components to improve the data quality of feedback storage. In our framework, new components were defined to solve the invalidity and sparse problems of feedback storage. Certainly, the trust assessment of CSP would be more accurate based on high-quality feedback ratings. The performance of the MLTM was evaluated using two different datasets based on a real Quality of Web Services dataset (QWS) and an artificial data set (Cloud-Armor), whose quality was reduced for the purpose of this study. Analytical values revealed that our proposed approach significantly outperformed other approaches even with the poor data quality of feedback storage.

     

Coordinated Cognitive Tethering in Dense Wireless Areas

This paper examines the resource gain that can be obtained from the creation of clusters of nodes in densely populated areas. A single node within each such cluster is designated as a “hotspot”; all other nodes then communicate with a destination node, such as a base station, through such hotspots. We propose a semi‐distributed algorithm, referred to as coordinated cognitive tethering (CCT), which clusters all nodes and coordinates hotspots to tether over locally available white spaces. CCT performs the following these steps: (a) groups nodes based on a modified k‐means clustering algorithm; (b) assigns white‐space spectrum to each cluster based on a distributed graph‐coloring approach to maximize spectrum reuse, and (c) allocates physical‐layer resources to individual users based on local channel information. Unlike small cells (for example, femtocells and WiFi), this approach does not require any additions to existing infrastructure. In addition to providing parallel service to more users than conventional direct communication in cellular networks, simulation results show that CCT can increase the average battery life of devices by 30%, on average.     

Local periocular vaccination protects against eye disease more effectively than systemic vaccination following primary ocular herpes simplex virus infection in rabbits

Vaccination of experimental animals can provide efficient protection against ocular herpes simplex virus type 1 (HSV-1) challenge. Although it is suspected that local immune responses are important in protection against ocular HSV-1 infection, no definitive studies have been done to determine if local ocular vaccination would produce more efficacious protection against HSV-1 ocular challenge than systemic vaccination. To address this question, we vaccinated groups of rabbits either systemically or periocularly with recombinant HSV-2 glycoproteins B (gB2) and D (gD2) in MF59 emulsion or with live KOS (a nonneurovirulent strain of HSV-1). Three weeks after the final vaccination, all eyes were challenged with McKrae (a virulent, eye disease-producing strain of HSV-1). Systemic vaccination with either HSV-1 KOS or gB2/gD2 in MF59 did not provide significant protection against any of the four eye disease parameters measured (conjunctivitis, iritis, epithelial keratitis, and corneal clouding). In contrast, periocular vaccination with gB2/gD2 in MF59 provided significant protection against conjunctivitis and iritis, while ocular vaccination with live HSV-1 KOS provided significant protection against all four parameters. Thus, local ocular vaccination provided better protection than systemic vaccination against eye disease following ocular HSV-1 infection. Since local vaccination should produce a stronger local immune response than systemic vaccination, these results suggest that the local ocular immune response is very important in protecting against eye disease due to primary HSV-1 infection. Thus, for clinical protection against primary HSV-1-induced corneal disease, a local ocular vaccine may prove more effective than systemic vaccination.     

A three-stage damage detection method for large-scale space structures using forward substructuring approach and enhanced bat optimization algorithm

In this study, an efficient three-stage method is proposed for damage detection of large-scale space structures by employing forward substructuring approach, modal strain energy and enhanced bat algorithm (EBA) optimization. EBA is a modified version of BA that is proposed in this paper and used a passive congregation operator to improve the performance of standard BA. In the first stage, the global structure is divided into manageable substructures. The stiffness matrices of independent substructures are obtained based on Kron’s substructuring method. Then a modal strain energy-based index is employed to precisely locate the eventual damages of the structure. In the third stage, damage severities are estimated via EBA using the second-stage results. To demonstrate the ability of the proposed method for detection of multiple structural damages, large-scale space structures with different types of damage scenarios are considered. The results show that the proposed method can detect the exact locations and severity of damages highly accurate in space structures.

     

Benefits of EDC and linear receivers for short reach 40/100GE

An ongoing trend in datacom switches is to require optical transceivers to be smaller and have lower power dissipation in order to enable greater port densities. The transition from 1 GE to 10 GE was unusually slow for the Ethernet market due in part to the high cost. high power dissipation, and form factor of the optical module. The industry is now overcoming these hurdles with the transition to SFP + modules, which will enable more traditional Ethernet growth. Upcoming 40 GE and 100 GE are multilane protocols, presenting even greater challenges than 10 GE laced at its inception, potentially slowing their adoption. Leveraging SFP+ class technology such as simple EDC capabilities can lower cost and reduce module form factors, thus accelerating the transition to 40/100 GE interlace deployment.     

Subjective responses to emotional stimuli during labeling, reappraisal, and distraction.

Although multiple neuroimaging studies suggest that affect labeling (i.e., putting feelings into words) can dampen affect-related responses in the amygdala, the consequences of affect labeling have not been examined in other channels of emotional responding. We conducted four studies examining the effect of affect labeling on self-reported emotional experience. In study one, self-reported distress was lower during affect labeling, compared to passive watching, of negative emotional pictures. Studies two and three added reappraisal and distraction conditions, respectively. Affect labeling showed similar effects on self-reported distress as both of these intentional emotion regulation strategies. In each of the first three studies, however, participant predictions about the effects of affect labeling suggest that unlike reappraisal and distraction, people do not believe affect labeling to be an effective emotion regulation strategy. Even after having the experience of affect labels leading to lower distress, participants still predicted that affect labeling would increase distress in the future. Thus, affect labeling is best described as an incidental emotion regulation process. Finally, study four employed positive emotional pictures and here, affect labeling was associated with diminished self-reported pleasure, relative to passive watching. This suggests that affect labeling tends to dampen affective responses in general, rather than specifically alleviating negative affect. (PsycINFO Database Record (c) 2011 APA, all rights reserved)