Estimating the viewing parameters of random, noisy projections ofasymmetric objects for tomographic reconstruction

The ability to determine the viewing parameters of objects from their projections has enabled well established tomographic techniques to be employed in the 3D reconstruction of objects from images obtained via modalities where the orientation of the objects cannot be controlled. A method is described for the determination of the viewing parameters of randomly acquired projections of asymmetric objects. It extends upon the common lines algorithm by determining the relative orientation of projections from the location of lines of intersection among the Fourier transforms of the projections in 3D Fourier space. A new technique for finding the lines of intersection in the presence of translational displacement, and for subsequently finding the translational displacement, is presented. The complete algorithm is described and its efficacy is demonstrated using real data. A new technique for dealing with noise is also discussed     

A machine vision system for enhancing the teleoperation of an industrial robot

This paper describes a real-time vision system that enhances the teleoperation of a servicing tool used in the heat exchangers of nuclear power plants. The vision system is used to track the position of the tool as it moves over a sheet of tube ends. A map-based strategy is adopted for the estimation of the position. The system incorporates a novel method for a foreshortening correction that is applied prior to map referencing. A hypothesize and verify scheme locates two image features that correspond to two map features. An efficient scheme for extracting image features is developed to locate these two features (tube-end centers) in the image. Two different types of heat-exchanger tube sheets are accounted for. They are those with tube ends placed in a square grid and those with tube ends placed in a triangular grid. The map-based strategy minimizes the cumulative errors in the estimate of the tool head position. The resulting low-cost system has been tested on synthetic and real data. Performance results are given.     

Cross-cultural IS adoption in multinational corporations: A study of rationality

A common claim in the literature on Information Systems' implementation in the context of less developed economies or so-called “developing countries” is that the “Western” technology is at odds with the local cultural context, in particular it is believed to mismatch local rationality in the sense of the accepted ways of doing things. In this paper we investigate IS implementation in a company based in a “non-Western” context compared with IS adoption in another company in a “Western” country context. Seen as a particular form of decision-making, the adoption and implementation processes are analysed drawing on the literature on decision-making, rationality in “Western” and “non-Western” contexts. Presenting evidence from these two contexts we argue that multiple forms of rationality exist in any context and that national culture is only one aspect of actors' as well as researchers' sense-making of activities in any given context. Linking the cases back the literature we reflect on the implications of our findings for cross-cultural research of IT implementation.     

Doped oxides of cerium as inorganic colorants

The colour of inorganic colorants is based on metal ions such as cadmium, lead, chromium or cobalt, the majority of which are unfortunately potentially toxic. Thus, there is in a need to introduce alternative metal or metal oxides, which would be environmentally friendly and economically viable as a replacement for potentially toxic inorganic colorants. Rare earth-based colorants offer an additional opportunity for the development of optically pure colours. In this study, a replacement for potentially toxic colorants has been sought through the use of a rare earth metal ion, cerium. Appropriate doping of cerium oxides with molybdenum and iron gives an orange–red colorant. The conditions ideal for optimal colour have been standardised and the resultant colorant characterised through powder X-ray diffraction techniques, particle size measurement, etc. The colorants exhibit good hiding power and tinting strength.     

A harmonic retrieval framework for discontinuous motion estimation

Motion discontinuities arise when there are occlusions or multiple moving objects in the scene that is imaged. Conventional regularization techniques use smoothness constraints but are not applicable to motion discontinuities. In this paper, we show that discontinuous (or multiple) motion estimation can be viewed as a multicomponent harmonic retrieval problem. From this viewpoint, a number of established techniques for harmonic retrieval ran be applied to solve the challenging problem of discontinuous (or multiple) motion. Compared with existing techniques, the resulting algorithm is not iterative, which not only implies computational efficiency but also obviates concerns regarding convergence or local minima. It also adds flexibility to spatio-temporal techniques which have suffered from lack of explicit modeling of discontinuous motion. Experimental verification of our framework on both synthetic data as well as real image data is provided.     

Colored cool colorants based on rare earth metal ions

Colored pigments with high near infrared reflectance and not based on toxic metal ions like cadmium, lead and cobalt are being sought as cool colorants. Through appropriate doping two pigments Ce-Pr-Mo and Ce-Pr-Fe have been developed to offer a reddish brown and reddish orange color, respectively. These pigments have been characterized and found to be highly crystalline with an average size of 300 nm. A shift in band gap energy from 2.21 to 2.18 eV has been observed when Li₂CO₃ was used as a mineralizer. Scanning electron microscope-energy dispersive X-ray analysis (SEM-EDAX) measurement indicate a uniform grind shape and distribution of metal ion, with over 65% reflectance in the NIR region, these pigments can well serve as cool colorants.     

Acute and sub-acute toxicity studies using Shemamruthaa,a modified indigenous Siddha preparation,in Sprague-Dawley rats

Shemamruthaa (SM), an indigenous herbal formulation (Hibiscus rosa sinensis flowers, Phyllanthus emblica, and pure honey) in a definite ratio was analyzed using acute and sub-acute toxicity studies in Sprague-Dawley rats. The acute toxicity study for 72 h showed no adverse effects in behavior or mortality at a dosage of 75–2,000 mg/kg of BW. The sub-acute toxicity study at 50, 100, 250, and 500 mg/kg of BW for 30 days showed transient rises in the white blood cell count, and levels of hemoglobin, free fatty acids, high density lipoproteins, and cholesterol, and a significant decrease in the blood glucose, cholesterol, triglyceride, phospholipid, and LDL levels. Other parameters remained unchanged. Changes observed were significant only at the highest dosage of 500 mg/kg BW. These results proved that the drug SM is safe and not toxic.     

On the computation of motion from sequences of images-A review

Recent developments are reviewed in the computation of motion and structure of objects in a scene from a sequence of images. Two distinct paradigms are highlighted: (i) the feature-based approach and (ii) the optical-flow-based approach. The comparative merits/demerits of these approaches are discussed. The current status of research in these areas is reviewed and future research directions are indicated     

Design for success?: critical success factors in executive information systems development

Much of the literature on executive information systems (EIS) development provides lists of factors critical to the successful EIS development. This gives only limited insights into the relationship between the success factors and the development process. By drawing on an in-depth study of EIS development in a large manufacturing company, this paper seeks to provide a theoretically-based explanation of the process by which the relationship between key success factors and the EIS development operated. The rich insights gained from this empirical study are used to critique the main assumptions of the factor approach. This paper argues that a better understanding of the relationship between key success factors and the EIS development is required if success factors are to be of any guidance to the practitioners to develop effective information systems.     

Too close for comfort? Distance and engagement in interpretive information systems research

In this paper, we seek to explore the implications of the assumptions underlying interpretivism for the preferred relationship between the researcher and the research phenomenon. The growing interest in interpretive information systems research has drawn attention to the need to gain access to the interpretations of social actors. Various data-gathering methods are available to the researcher to achieve such access. These may be seen as located on a spectrum in terms of the degree of engagement between the researcher and the research subject. While engagement is not without its drawbacks from a research perspective, it may be argued that it enables good access to the sorts of data that interpretive researchers are seeking. Most of the research reported in the information systems (IS) field, however, has adopted relatively distant methods by which the researcher avoids intervention in the research context. Some of the characteristics of more engaged forms of research are illustrated through a discussion of a participant observation study of executive information systems development. This research has highlighted a number of issues that can be seen to be common to other data-gathering methods. Reasons for the neglect of engaged data-gathering methods are explored, and it is suggested that consideration of the issues it raises may contribute to more reflexive interpretive IS research practice.