Environment Analysis as a Basis for Designing Multimodal and Multidevice User Interfaces

In this article, we present a practical approach to analyzing mobile usage environments. We propose a framework for analyzing the restrictions that characteristics of different environments pose on the user's capabilities. These restrictions along with current user interfaces form the cost of interaction in a certain environment. Our framework aims to illustrate that cost and what causes it. The framework presents a way to map features of the environment to the effects they cause on the resources of the user and in some cases on the mobile device. This information can be used for guiding the design of adaptive and/or multimodal user interfaces or devices optimized for certain usage environments. An example of using the framework is presented along with some major findings and three examples of applying them in user interface design.     

Time-out in user interface: the case of mobile text input

In many user interfaces with restricted input capabilities, a time-out is used to automatically change the user interface (UI) from one mode to another. In this paper, we study the learning of time-outs and the effect of feedback on it in the case of mobile phone text entry. The effects of three different feedback schemes (auditory/visual/no feedback) on the learning of two different time-out lengths were compared. We measured the response time (RT) from the time-out occurrence to the time of the users action. Error rates and the development of the RTs in different schemes were used as measures of learning. We also studied if the users learned to estimate the time-out lengths, or if they just reacted to the available feedback. There were three main findings. Without feedback, RTs had a great variation. Auditory feedback enabled faster RTs than visual feedback. Finally, we found evidence of short-term learning, but not much of a lasting effect. The possible application of adapting time-out length to user RT is discussed.     

Active fault tolerant control for nonlinear systems with simultaneous actuator and sensor faults

The goal of this paper is to describe a novel fault tolerant tracking control (FTTC) strategy based on robust fault estimation and compensation of simultaneous actuator and sensor faults. Within the framework of fault tolerant control (FTC) the challenge is to develop an FTTC design strategy for nonlinear systems to tolerate simultaneous actuator and sensor faults that have bounded first time derivatives. The main contribution of this paper is the proposal of a new architecture based on a combination of actuator and sensor Takagi-Sugeno (T-S) proportional state estimators augmented with proportional and integral feedback (PPI) fault estimators together with a T-S dynamic output feedback control (TSDOFC) capable of time-varying reference tracking. Within this architecture the design freedom for each of the T-S estimators and the control system are available separately with an important consequence on robust L ₂ norm fault estimation and robust L ₂ norm closed-loop tracking performance. The FTTC strategy is illustrated using a nonlinear inverted pendulum example with time-varying tracking of a moving linear position reference.     

Effect of HBT on the stability of laccase during the decolourization of textile wastewaters

BACKGROUND: This study concerns the assessment of laccase stability during textile industry effluent treatment by laccase in the presence of a mediator RESULTS: The effects of 1‐hydroxybenzotriazole (HBT) and textile wastewater on the stability of a crude laccase prepared from cultures of Trametes trogii during the process of textile industry effluent decolourization were determined. HBT was essential for decolourization of effluent by laccase. Decolourization efficiency decreased when effluent was repeatedly added to the reaction mixture, suggesting inhibition of laccase during the process. Stability of the laccase was not affected by different concentrations of effluent, but inactivation was proportional to HBT concentration. CONCLUSION: Experimental results showed that a redox mediator such as HBT was required for high decolourization rate of textile industry effluent; however free radicals generated from this compound inactivated the laccase used in the process. Copyright © 2009 Society of Chemical Industry     

Live Load Distribution in Girder Bridges Subject to Oversized Trucks

A significant challenge facing motor carriers and engineers in this nation is the limitation of vehicle size and weight based on pavement and bridge capacity. However, the current demands of society and industry occasionally require a truck to carry a load that exceeds the size and weight of the legal limit. In these cases, engineering analysis is required before a permit is issued to ensure the safety of the structures and roadways on the vehicle's route. A truck with a wheel gauge larger than the standard 1.83 m (6 ft) gauge requires additional engineering effort because the wheel load girder distribution factors (GDFs) established by AASHTO cannot be used to accurately estimate the live load in the girders. In this study, the finite-element method is used to develop modification factors for the AASHTO flexure and shear GDFs to account for oversized trucks. The results of the analysis showed that the use of the proposed modification factors with the specification-based GDFs can help increase the allowable loads on slab-on-girder bridges.     

A comparison analysis of prefiltering methods in space-time trellis-based reduced-state turbo-detection

In this paper, we investigate two different prefiltering strategies, i.e., multiple input multiple output (MIMO) channel shortening and MIMO whitened matched filtering, to decode iteratively a space time bit interleaved coded modulation transmitted over MIMO block fading intersymbol interference channels using a trellis-based post-detector. Indeed, resorting to such front-ends allows significant complexity gain when compared to the optimal maximum a posteriori-based turbo-receiver. While those two approaches have been exhaustively visited in the past, their fair comparison in terms of trade-off between complexity and performance has – to our knowledge – never been tackled before. This paper aims at giving some valuable insights about the respective benefits of these two prefiltering methods with respect to the channel characteristics and overall receiver complexity.     

Transient electromagnetic field of a vertical magnetic dipole on atwo-layer conducting Earth

The transient field-frequency domain of magnetic dipole in a two-layered conducting Earth has been studied. It is obtained as a summation of waveguide modes plus contributions from branch cuts in the complex-plane of the longitudinal wave number. Results can be used to evaluate numerical solutions of more complicated modeling algorithms     

Determination of flavan-3-ols and trans-resveratrol in grapes and wine using HPLC with fluorescence detection

Concentrations of trans-resveratrol, catechin and epicatechin were analyzed in musts and wines produced from seven red and four white grape cultivars from various wine growing regions of Turkey. Phenolics were quantified using an HPLC method optimized for the separation of wine phenolics. Wine samples contained higher phenolics levels than the corresponding musts. With the exception of Semillion, white wines and musts contained lower concentrations of phenolics than red wines and musts. However, the white cultivar Semillion had the highest concentrations of catechin and epicatechin among all wine and must samples. Semillion wine catechin and epicatechin were 13.7 and 11.8 mg/L, respectively. The highest level of trans-resveratrol among the white cultivars was found in Narince wine (1.93 mg/L). Within the red wine and must cultivars, Bo?azkere, Öküzgozü, and Cabernet contained the highest concentrations of flavan-3-ols and trans-resveratrol. Catechin was the major phenolic in all wines and most musts. Epicatechin was the major phenolic in 6 of the 11 must samples, but none of the wine samples. trans-Resveratrol was generally found in lowest concentrations in both wines and musts.     

Temperature modeling and measurement of an electrokinetic separation chip

This work presents experimental [infrared (IR) thermography] and computational (finite element model) results of temperature distributions of an electrokinetic separation chip. Thermal characteristics of both the electrolyte solution and the polymer chip (SU-8) are taken into account in modeling temperature distributions during electrokinetic flow. Multiphysics and multiscale simulation couples electrostatics, heat transfer, and fluid dynamics. The accompanying IR thermography is a non-contact method, which can measure fractional temperature differences with sub-second time resolution. Any structures or temperature marker molecules interfering with the experiment are not needed. Nominal spot size in the IR measurements is 30 μm with a field of view of several millimeters enabling both local and chip-scale temperature monitoring simultaneously. As a result, we present a computer model for electrokinetic chips, which enables simulation of fractional temperature changes during electrophoresis under real operating conditions. The accuracy of the model is within ±1°C when the deviation in electrochemical processes is taken into account. The simulation results also suggest that the temperature on the chip surface qualitatively reflects the temperature inside the microchannel with an average offset of 1–2°C.