ATCA HI Observations of the NGC 6845 Galaxy Group

We present the results of ATCA HI line and 20-cm radio continuum observations of the galaxy Quartet NGC 6845. The HI emission extends over all four galaxies but can only be associated clearly with the two spiral galaxies, NGC 6845A and B, which show signs of strong tidal interaction. We derive a total HI mass of at least 1.8 x 10^10 Msun, most of which is associated with NGC 6845A, the largest galaxy of the group. We investigate the tidal interaction between NGC 6845A and B by studying the kinematics of distinct HI components and their relation to the known HII regions. No HI emission is detected from the two lenticular galaxies, NGC 6845C and D. A previously uncatalogued dwarf galaxy, ATCA J2001-4659, was detected 4.4' NE from NGC 6845B and has an HI mass of about 5 x 10^8 Msun. No HI bridge is visible between the group and its newly detected companion. Extended 20-cm radio continuum emission is detected in NGC 6845A and B as well as in the tidal bridge between the two galaxies. We derive star formation rates of 15 to 40 Msun/yr.Comment: accepted, to be published in MNRAS, for more details and the full ps-file see http://www.atnf.csiro.au/people/bkoribal/ngc684

MACT Implementation at an Organic Chemical Manufacturing Facility: Human Health Risk Reduction

Human health risk assessments are used by environmental regulatory agencies to determine risk from Hazardous Air Pollutants (HAPs). In this study, the Human Exposure Model (HEM-3) was used to compare the cancer and non-cancer inhalation health effects of a single organic chemical manufacturing facility in Geismar, Louisiana prior to and after Maximum Achievable Control Technologies (MACT) were implemented. The results indicate significant reductions in both cancer risk and non-cancer hazards. The analysis also indicated that the equivalent cancer risk reduction could have been achieved by addressing MACT in only one production process and one single pollutant (ethylene dichloride) within that process. This demonstrates the value that these risk assessments have at evaluating emissions at the facility level, and how they could be used in the control strategy decision making process

MACT Implementation at an Organic Chemical Manufacturing Facility: Human Health Risk Reduction

Human health risk assessments are used by environmental regulatory agencies to determine risk from Hazardous Air Pollutants (HAPs). In this study, the Human Exposure Model (HEM-3) was used to compare the cancer and non-cancer inhalation health effects of a single organic chemical manufacturing facility in Geismar, Louisiana prior to and after Maximum Achievable Control Technologies (MACT) were implemented. The results indicate significant reductions in both cancer risk and non-cancer hazards. The analysis also indicated that the equivalent cancer risk reduction could have been achieved by addressing MACT in only one production process and one single pollutant (ethylene dichloride) within that process. This demonstrates the value that these risk assessments have at evaluating emissions at the facility level, and how they could be used in the control strategy decision making process

Basic Characteristics of Photography Courses in Washington State High Schools

The purposes of this study were (1) to determine whether photography is being taught as a high school class; (2) to determine the factors which influence the offering of such a class; and (3) to discover the characteristics of such a class when offered

Simulation of ultrasonic lamb wave generation, propagation and detection for an air coupled robotic scanner

A computer simulator, to facilitate the design and assessment of a reconfigurable, air-coupled ultrasonic scanner is described and evaluated. The specific scanning system comprises a team of remote sensing agents, in the form of miniature robotic platforms that can reposition non-contact Lamb wave transducers over a plate type of structure, for the purpose of non-destructive evaluation (NDE). The overall objective is to implement reconfigurable array scanning, where transmission and reception are facilitated by different sensing agents which can be organised in a variety of pulse-echo and pitch-catch configurations, with guided waves used to generate data in the form of 2-D and 3-D images. The ability to reconfigure the scanner adaptively requires an understanding of the ultrasonic wave generation, its propagation and interaction with potential defects and boundaries. Transducer behaviour has been simulated using a linear systems approximation, with wave propagation in the structure modelled using the local interaction simulation approach (LISA). Integration of the linear systems and LISA approaches are validated for use in Lamb wave scanning by comparison with both analytic techniques and more computationally intensive commercial finite element/difference codes. Starting with fundamental dispersion data, the paper goes on to describe the simulation of wave propagation and the subsequent interaction with artificial defects and plate boundaries, before presenting a theoretical image obtained from a team of sensing agents based on the current generation of sensors and instrumentation

Big Homotopy Theory

Cannon and Conner developed the theory of big fundamental groups. This is meant to expand on the notion of fundamental group and is a powerful tool that can be used for distinguishing spaces that are not distinguishable using the fundamental group. Turner proved several classical results, such as covering theory and Seifert-VanKampen for big fundamental groups. The purpose of this paper is to expand on the the theory, to refine the definitions, and to give more examples. Also, in this paper, we define big higher homotopy groups analogous to the way classical higher homotopy groups are defined

An annotated list of books suitable for bibliotherapeutic use

Thesis (Ed.M.)--Boston Universit

Pilot-study use of the tachistoscope in elementary grade reading

The classroom teacher in the modern elementary school faces many challenges. Among these are limited classroom facilities, large-size classes, double session, wide ability range of pupils, supplementary assignments, and often inadequate material resources. In spite of these problems, the teacher strives to advance his pupils as far as their interest and ability and skill as a teacher will permit. New ideas in teaching, additional means of motivation, and improved techniques of instruction attract his interest. Because reading plays such an important role in the elementary school programs, the teacher is especially attracted to suggestions and improved techniques of teaching this basic skill. The use of tachistoscopic devices to aid in the teaching of reading has recently been advanced. The advocates of tachistoscopic techniques propose that training in eye-movement skills, perception span, and flash recognition will aid in the development of the total reading skill of pupils. The present investigation proposed to explore this area of learning through a controlled experiment in the use of a tachistoscopic in the reading program of a typical elementary school