Effect of Oxide Defect Structure on the Electrical Properties of ZrO2

The defect structure of monoclinic ZrO₂ was studied by measuring the transfer numbers and electrical conductivity as functions of O₂ pressure and temperature. The data suggest a defect structure of doubly ionized oxygen vacancies at low pressures, i.e. <10⁻¹⁹ atm, and singly ionized oxygen interstitials at pressures >10⁻⁹ atm. Zirconia is primarily an ionic conductor below #700°C and an electronic conductor at 700° to 1000°C for 10⁻²²≤P_o2≤1 atm.     

Dominant graphs for rectilinear network design with barriers

Given a set of points on a Cartesian plane and the coordinate axes, the rectilinear network design problem is to find a network, with arcs parallel to either one of the axes, that minimizes the fixed and the variable costs of interactions between a specified set of pairs of points. We show that, even in the presence of arbitrary barriers, an optimal solution to the problem (when feasible) is contained in a grid graph defined by the set of given points and the barriers. This converts the spatial problem to a combinatorial problem. Finally we show connections between the rectilinear network design problem and a number of well-known problems. Thus this paper unifies the known dominating set results for these problems and extends the results to the case with barriers.     

Balanced gait generations of a two-legged robot on sloping surface

In this paper, dynamically balanced gait generation problem of a 7-DOF two-legged robot moving up and down through the sloping surface is presented. The gait of the lower links during locomotion is obtained after assuming suitable trajectories for the swing leg and hip joint. The trunk motion is initially generated based on the concept of static balance, which is different from the well-known semi-inverse method and then checked for its dynamic balance calculated using the concept of Zero-Moment Point (ZMP). Lagrange–Euler formulation is attempted for the determination of joint torques. Average power consumption at each joint is then determined based on the computed torques. Moreover, the variations of dynamic balance margin and average power consumption are studied for both ascending and descending through the sloping surface. Both of them are found to be more for the ascending gait generation compared to those for the descending case. The effects of variations of the slope have also been studied on the average dynamic balance margin and power consumption for both the cases.     

Phenotypic and genotypic characterisation of Lactobacilli isolated from camel cheese produced in India

Thirty‐two Lactobacilli strains were isolated from four samples of camel cheese collected from Bikaner, India. These isolates were identified based on phenotypic and genotypic characteristics. Sequencing of 16S rDNA was performed for species identification and diversity analysis. Lactobacillus delbrueckii and Lb. fermentum were found to be dominant species followed by Lb. plantarum and Lb. casei. On evaluation of technological properties of these isolates, 20 isolates were observed to be good acid producers, eight were found positive for citrate utilisation and 11 showed presence of Prtp gene. Isolates obtained can be potential for development of defined strain starter for camel cheese.     

A METHOD OF OBTAINING LANGMUIR-HINSHELWOOD PARAMETERS FROM PULSED MICROCATALYTIC REACTORS

A method of calculating first-order Langmuir-Hinshelwood parameters from a rectifying plot is presented. This plot is based on the variation of conversion with pulse volume in a pulsed microcatalytic reactor. The method has been extended to treat the cases of (a) carrier gas participation in the kinetics, and (b) change in volume during reaction. It is possible to extend the method to other irreversible kinetic expressions as well. A non-broadening Gaussian pulse and other simplifying assumptions are made which allow an analytical solution for the instantaneous conversion in the pulse. The method is applied to calculate the values of the Langmuir-Hinshelwood parameters for the hydrogenation of propylene over unsupported molybdenum sulfide. The decrease in volume during this reaction has little effect on the estimated values of the kinetic parameters; the rectifying plot based on the equation neglecting volume change gives approximately the same results as that based on the equation accounting for volume change.     

DEVELOPMENT OF A HIGH-MOISTURE SHELF-STABLE GRATED CARROT PRODUCT USING HURDLE TECHNOLOGY

Carrot (Daucus carota) can be highly perishable and difficult to preserve fresh for long periods at ambient temperature and humidity. Studies on grated carrots were carried out for the development of a shelf‐stable moist‐preservation process based on infusion of additives using hurdle technology. Additives comprising 3.0% sodium chloride (to reduce water activity [A_w] to 0.94), 0.9% citric acid (to reduce pH to below 4.5), 1.0% sodium citrate and 0.2% sodium benzoate (as antimicrobial agents) were followed by partial dehydration. The product was stored in flexible polymeric pouches. The physical, chemical and pathological stability was monitored during storage at ambient temperatures (19–33C). The partially dehydrated grated carrots (moisture 66.2%) were acceptable for more than six months at ambient temperature with the retention of carotenoid up to 82.5%. The product was microbiologically safe throughout the study.     

Fuzzy clustering of mechanisms

During the course of development of Mechanical Engineering, a large number of mechanisms (that is, linkages to perform various types of tasks) have been conceived and developed. Quite a few atlases and catalogues were prepared by the designers of machines and mechanical systems. However, often it is felt that a clustering technique for handling the list of large number of mechanisms can be very useful, if it is developed based on a scientific principle. In this paper, it has been shown that the concept of fuzzy sets can be conveniently used for this purpose, if an adequate number of properly chosen attributes (also called characteristics) are identified. Using two clustering techniques, the mechanisms have been classified in the present work and in future, it may be extended to develop an expert system, which can automate type synthesis phase of mechanical design. To the best of the authors?? knowledge, this type of clustering of mechanisms has not been attempted before. Thus, this is the first attempt to cluster the mechanisms based on some quantitative measures. It may help the engineers to carry out type synthesis of the mechanisms.     

DETERMINANTS OF SATISFACTION IN MIDDLE-MANAGEMENT PERSONNEL.

RESPONSES TO A QUESTIONNAIRE WERE OBTAINED FROM 93 MIDDLE MANAGERS WHERE SS INDICATED THE EXTENT TO WHICH 13 JOB-CONTENT AND 13 JOB-CONTEXT FACTORS CONTRIBUTE TO THE FEELING OF SATISFACTION AND DISSATISFACTION IN THE PRESENT AND THE IMAGINARY JOB SITUATIONS. RESULTS INDICATE THAT, CONTRARY TO THE CONVENTIONAL ASSUMPTION OF BIPOLARITY, SATISFACTION AND DISSATISFACTION REPRESENT 2 DISTINCT AND SEPARATE FEELINGS, AND BOTH GROUPS OF FACTORS MAY ACT AS SATISFIERS AND AS DISSATISFIERS. THE PRESENT RESULTS ARE ALSO COMPARED WITH (1) THE RESULTS OBTAINED IN A STUDY OF SKILLED WORKERS, AND (2) THE AMERICAN STUDIES. THE FINDINGS CAST SERIOUS DOUBTS ON THE GENERALITY OF THE HERZBERG-MAUSNER-SNYDERMAN MOTIVATOR-HYGIENE THEORY. (26 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

FUZZY-GENETIC ALGORITHMS AND TIME-OPTIMAL OBSTACLE-FREE PATH GENERATION FOR MOBILE ROBOTS

This paper, describes a new yet efficient technique based on fuzzy logic and genetic algorithms (Gas) to solve the find-path problems of a mobile robot, which is formulated as a nonlinear programming problem. In the proposed algorithm, a fuzzy logic controller is used to find obstracle-free directions locally and GAs are used as optimizer to find optimal/near-optimal locations along the obstracle-free directions. This algorithm is found to be more efficient than a steepest gradient descent method. Although the fuzzy-GA method is shown to find slightly inferior or similar solutions to those found using the best-known tangent-graph and A* algorithms, it is computationally faster than them. Moreover, the fuzzy-GA approach is practically more viable than the tangent-graph method, because of former's lesser sensitivity to the number and type of obstacles. The efficiency of the proposed method demonstrated in this paper suggests that it can be extended to solve motion planning problems having moving obstacles.     

SENSITIVITY ANALYSIS of ASEPTIC PROCESS SIMULATIONS FOR FOODS CONTAINING PARTICULATES1

A sensitivity analysis of a computer model, simulating heat transfer into particulate foods processed in a continuous aseptic system was conducted to determine how the model reacts to the variations in selected product and process input parameters depending on simulation types, namely, “Total”, “F₀ Hold” and “Hold Only”. Three major output variables, namely, holding tube required to destroy 6 D of Clostridium sporogenes (PA3679), destruction of thiamine and inactivation of peroxidase were selected for the sensitivity analysis. Theoretical results indicated that basically no difference between the “Total” system approach and the “F₀ Hold” approach was found on the model prediction. Particle size, particle thermal properties such as density and specific heat were the most sensitive parameters (within the range investigated) among product parameters which influence holding tube length required, thiamine and peroxidase retention while fluid properties such as fluid thermal conductivity and viscosity were less susceptible to affect the model prediction regardless of simulation types. Among process parameters, product flow rate and product initial temperature seemed to be the most critical parameters within the range covered in this study while rotor speed seemed to be one of the least critical parameters to influence the model prediction regardless of simulation types.