Tris(trimethyl-stannyl,-germyl, -sijyl)borates

137-13

Effects of alarms on control of robot teams

Annunciator driven supervisory control (ADSC) is a widely used technique for directing human attention to control systems otherwise beyond their capabilities. ADSC requires associating abnormal parameter values with alarms in such a way that operator attention can be directed toward the involved subsystems or conditions. This is hard to achieve in multirobot control because it is difficult to distinguish abnormal conditions for states of a robot team. For largely independent tasks such as foraging, however, self-reflection can serve as a basis for alerting the operator to abnormalities of individual robots. While the search for targets remains unalarmed the resulting system approximates ADSC. The described experiment compares a control condition in which operators perform a multirobot urban search and rescue (USAR) task without alarms with ADSC (freely annunciated) and with a decision aid that limits operator workload by showing only the top alarm. No differences were found in area searched or victims found, however, operators in the freely annunciated condition were faster in detecting both the annunciated failures and victims entering their cameras' fields of view. Copyright 2011 by Human Factors and Ergonomics Society, Inc. All rights reserved

A Geological Appraisal of Slope Instability and Proposed Remedial Measures at Kaliasaur Slide on National Highway, Garwal Himalaya

For over six decades Kaliasaur landslide (Lat. 30° 14\u27 30 N, Long. 78° 55\u27 50 E) is a nightmare on the Hardwar-Badrinath road in the Garhwal Himalaya. Located on a sharp bend on the left bank of river Alaknanda, it has emerged as a multi-tier repetitive major landslide, retrogressive in nature. Both surficial and deep seated movements have been monitored. The sliding in the upper layers have been predominantly in the colluvium but where interfaces of quartzite and shale participates, the sliding surfaces have been better defined and discrete. In the present paper, the authors have highlighted the geological, geomorphological and morphometric parameters to diagnose the factors responsible for instability of slope and the magnitude of the problems involved. A scheme of remedial measures which .include modification of existing drainage pattern, timber piling for stitching of debris cover on to the slope, construction of retaining walls and putting back the vegetation on the slope are recommended for control of the landslide

Mathematical Modeling of Particle Stratification in Jigs

Recognizing mathematical modeling as a powerful tool for systematic process analysis and control, this paper attempts to critically'review the theories and mathem-atical models which have been advanced to explain and simulate the behaviour ofjigg ing process. The existing literature on mathematical modeling and quantitative analysis of jigging has been divided into six subheads : (i) classical theory, (ii) potential theory, (iii) dispersion models, (iv) energy dissipation theory, (v) stochastic analysis and (vi) empirical models. A new modeling approach based on Newtonian mechanics is used to describe the stratification behavior of particles in jig. In this approach,the motion of solid material is treated using the discrete element method (DEM) while the corre-sponding motion of the liquid is determined by marker and cell (MAC) technique. For illustration purpose, a jig bed consisting of 100 particles of two different densities is simulated. Preliminary results show that the model predicts the stratification of particles reasonably well

A Mathematical Model to Characterize Volatile Matter Evolution during Carbonisation in Metallurgical Coke Ovens

The carbonisation mechanism in the coke oven chamber is quite complex and, although much useful information has been generated by empirical studies on both industrial batteries and pilot ovens, attempts to mathematically model the coke oven phenomena met with only limited success. In this study, a mathematical model to simulate volatile matter evolution during carbonisation process for Indian coals has been developed. This model is a part of the endeavour to develop a rigorous mathem- atical model to simulate the main physical, chemical changes and transient heat transfer phenomena occurring during thermal decomposition of coals in coke oven carbonisation. To have sufficient generality for the applications to coke oven practices, the mathematical model describes the kinetics of release of main volatile matter constituents, thereby, permitting the changes in the mass and composition of solid residue to be estimated by element balances. The prediction of volatile matter evolution has been made from coal ultimate analysis and heating profile based on the principles of kinetics and rate phenomena. The aim of this mathematical model is to predict the yield and composition of volatile matter as a function of charge temperature and to relate these to the changes in the semi-coke composition for some typical Indian coals used for coke making in the metall-urgical coke ovens. The quantity of volatile matter loss from coal during carbonisation was also determined experimentally using a standard thermogravimetric analyser (TGA), in which the weight of the sample undergoing test is monitored continuously while the sample is heated at a constant rate. The computer based mathematical model predictions for volatile matter yield are verified with the experimental results and found to be in good agreement

Thin Layer Chromatography of Pesticides and Their Residues

Recent progress in the analysis of organo-phosphorus, organo-chlorine, carbamate, urea, uracil pesticides and their residues by thin layer chromatorgraphic methods employing chemical and enzymatic methods is reviewed

A mathematical model to characterize volatile matter evolution during carbonisation in metallurgical coke ovens

The carbonisation mechanism in the coke oven chamber is quite complex and, although much useful information has been generated by empirical studies on both industrial batteries and pilot ovens, attempts to mathematically model the coke oven phenomena met with only limited success. In this study, a mathematical model to simulate volatile matter evolution during carbonisation process for Indian coals has been developed. This model is a part of the endeavour to develop a rigorous mathematical model to simulate the main physical , chemical changes and transient heat transfer phenomena occurring during thermal decomposition of coals in coke oven carbonisation. To have sufficient generality for the applications to coke oven practices, the mathematical model describes the kinetics of release of main volatile matter constituents , thereby, permitting the changes in the mass and composition of solid residue to be estimated by element balances. The prediction of volatile matter evolution has been made from coal ultimate analysis and heating profile based on the principles of kinetics and rate phenomena. The aim of this mathematical model is to predict the yield and composition of volatile matter as a function of charge temperature and to relate these to the changes in the semi-coke composition for some typical Indian coals used for coke making in the metallurgical coke ovens. The quantity of volatile matter loss from coal during carbonisation was also determined experimentally using a standard thermogravimetric analyser (TGA), in which the weight of the sample undergoing test is monitored continuously while the sample is heated at a constant rate. The computer based mathematical model predictions for volatile matter yield are verified with the experimental results and found to be in good agreement