The CO-catalyzed conversion of H2S to H2 + sulfur part 2. The thermal decomposition of COS

The pyrolysis of COS has been studied over the temperature range 300 to 750°C using a variety of catalysts. The observed product distribution confirmed that two parallel reaction paths: 2 COS → 2 CO S₂ (2) and 2 COS → CO₂ + CS₂ (4) are involved in the decomposition. The decomposition yield increased with rising temperature, accompanied with a shift in selectivity. At temperatures lower than ～700°C the disproportionation reaction 4 was predominant, whereas at temperatures higher than 700°C, reaction 2 was favoured. In the high-temperature region (700 to 750°C) it was possible to achieve full suppression of reaction 4 with added CS₂. The pyrolysis of COS was also studied in a reactor packed with quartz chips without catalysts at high temperatures. Between 800 and 900°C, up to 99% conversion (with respect to the thermodynamic limit) could be achieved, with the almost complete absence of the disproportionation reaction 4. The results point to the commercial potential in the two-step reaction sequence: for the economic conversion of hydrogen sulfide to hydrogen and sulfur.     

Surface-free energy analysis of hydrolyzed ethylene-vinyl acetate copolymers

Ethylene-vinyl acetate (E-VA) copolymers containing 12, 28, and 40 wt% of vinyl acetate, ethylene-vinyl acetate-vinyl alcohol terpolymers obtained by partial hydrolysis of (E-VA) copolymers and ethylene-vinyl alcohol (E-VOH) copolymers obtained by complete hydrolysis of (E-VA) copolymers were investigated by one-liquid contact-angle method. The polar force component of surface-free energy (γ) of copolymers drastically increased by the substitution of the acetate groups with hydroxyl groups. The dispersion force component (γ) of copolymers increased only slightly with the hydrolysis degree and deviated largely from the additivity law in regards of the surface area functions. The surface-free energy analysis of the cross-linked ethylene-vinyl alcohol and surface-hydrolyzed ethylene-vinyl acetate copolymers was also carried out.     

Fault detection on robot manipulators using artificial neural networks

Nowadays, gas welding applications on vehicle’s parts with robot manipulators have increased in automobile industry. Therefore, the speed of end-effectors of robot manipulator is affected on each joint during the welding process with complex trajectory. For that reason, it is necessary to analyze the noise and vibration of robot’s joints for predicting faults. This paper presents an experimental investigation on a robot manipulator, using neural network for analyzing the vibration condition on joints. Firstly, robot manipulator’s joints are tested with prescribed of trajectory end-effectors for the different joints speeds. Furthermore, noise and vibration of each joint are measured. And then, the related parameters are tested with neural network predictor to predict servicing period. In order to find robust and adaptive neural network structure, two types of neural predictors are employed in this investigation. The results of two approaches improved that an RBNN type can be employed to predict the vibrations on industrial robots.     

Detecting emotional state of a child in a conversational computer game

The automatic recognition of user’s communicative style within a spoken dialog system framework, including the affective aspects, has received increased attention in the past few years. For dialog systems, it is important to know not only what was said but also how something was communicated, so that the system can engage the user in a richer and more natural interaction. This paper addresses the problem of automatically detecting “frustration”, “politeness”, and “neutral” attitudes from a child’s speech communication cues, elicited in spontaneous dialog interactions with computer characters. Several information sources such as acoustic, lexical, and contextual features, as well as, their combinations are used for this purpose. The study is based on a Wizard-of-Oz dialog corpus of 103 children, 7–14 years of age, playing a voice activated computer game. Three-way classification experiments, as well as, pairwise classification between polite vs. others and frustrated vs. others were performed. Experimental results show that lexical information has more discriminative power than acoustic and contextual cues for detection of politeness, whereas context and acoustic features perform best for frustration detection. Furthermore, the fusion of acoustic, lexical and contextual information provided significantly better classification results. Results also showed that classification performance varies with age and gender. Specifically, for the “politeness” detection task, higher classification accuracy was achieved for females and 10–11 years-olds, compared to males and other age groups, respectively.     

Inverse propagation of uncertainties in finite element model updating through use of fuzzy arithmetic

A fuzzy finite element model updating (FFEMU) method is presented in this study for the damage detection problem. The uncertainty caused by the measurement noise in modal parameters is described by fuzzy numbers. Inverse analysis is formulated as a constrained optimization problem at each α-cut level. Membership functions of each updating parameter which correspond to reduction in bending stiffness of the finite elements is determined by minimizing an objective function using a hybrid version of genetic algorithms (GA) and particle swarm optimization method (PSO) which is very efficient in terms of accuracy and robustness. Practical evaluation of the approximate bounds of the interval modal parameters in FFEMU iterations is addressed. A probabilistic analysis is performed using Monte Carlo simulation (MCS) and the results are compared with presented FFEMU method. It is apparent from numerical simulations that the proposed method is well capable in finding the membership functions of the updating parameters within reasonable accuracy. It is also shown that the results obtained by FFEMU are in good agreement with the MCS results while FFEMU is not as computationally expensive as the MCS method. Nevertheless, the proposed FFEMU do not required derivatives of the objective function like existing methods except in the deterministic case.     

Application of Artificial Neural Networks (ANNs) in Wine Technology

In recent years, neural networks have turned out as a powerful method for numerous practical applications in a wide variety of disciplines. In more practical terms neural networks are one of nonlinear statistical data modeling tools. They can be used to model complex relationships between inputs and outputs or to find patterns in data. In food technology artificial neural networks (ANNs) are useful for food safety and quality analyses, predicting chemical, functional and sensory properties of various food products during processing and distribution. In wine technology, ANNs have been used for classification and for predicting wine process conditions. This review discusses the basic ANNs technology and its possible applications in wine technology.     

A geographic information system‐based model for economical and eco‐friendly high‐speed railway route determination using analytic hierarchy process and least‐cost‐path analysis

In this study, geographic information system (GIS)‐based network analysis and analytic hierarchy process (AHP) methods were applied to the Erzincan–Trabzon segment of the Turkish high‐speed railway (HSR) project. A new hybrid route, which considers both economic and environmental criteria, was created and compared with three different routes from various preconstruction studies. The route‐generating analysis included the eight parameters (criteria) of slope, geology, soil quality, rivers, protected areas, roads, land cover, and lakes. The optimum route for connecting the port of Trabzon to Turkey's interior via HSR was generated. The weights for determining the route were tested for sensitivity. The study demonstrated the efficiency of GIS and AHP integration in generating optimum routes for HSR projects according to given databases. All these GIS and AHP analyses were applied automatically with our novel GIS extension for determining optimum HSR routes. The final route has preserved cultural and historical structures, environmental integrity. The new hybrid route also decreased construction costs by approximately 12%, and the least‐cost‐path analysis confirmed the environmental efficiency of the route.     

Mechanical and Antibacterial Properties of Injection Molded Polypropylene/TiO2 Nano-Composites:Effects of Surface Modification

Polypropylene (PP)/titanium dioxide (TiO2) nano-composites were prepared by melt compounding with a twin screw extruder. Nanoparticles were modified prior to melt mixing with maleic anhydride grafted styrene-ethylene-butylene-styrene (SEBS-g-MA) and silane. The composites were injection molded and mechanical tests were applied to obtain tensile strength, elastic modulus and impact strength. Antibacterial efficiency test was applied on the injection molded composite plaques by viable cell counting technique. The results showed that the composites including SEBS-g-MA and silane coated TiO2 gave better mechanical properties than the composites without SEBS-g-MA. Antibacterial efficiency of the composites varied according to the dispersion and the concentration of the particles and it was observed that composites at low content of TiO2 showed higher antibacterial property due to the better photocatalytic activity of the particles during UV exposure.     

Design of circulation axes in densely used polyclinic waiting halls

The purpose of this article is to explore whether spatial definition can affect the perceptual evaluations of users in highly dense conditions. The particular spatial definition studied in this research was the relationship between circulation axes and seating areas of a waiting hall. In crowded public interiors, it is generally assumed that users feel less comfortable and less safe. As suggested in this work, the disturbance is much higher even where there are less-defined boundaries (where people pass through from different directions) and the space is more likely to be perceived negatively. To research this, a study was carried out in three waiting halls of a large polyclinic building: a clinic waiting hall, a pharmacy waiting hall, and an X-ray waiting hall, spatially designed different from each other. Results from 240 patients showed that the least identifiable waiting hall design was perceived the most negatively. The effect of gender on performance appraisal task was also examined. Compared to females, male users perceived the space more positively than female users.