A high-fidelity N-body ephemeris generator for satellites in Earth orbit

A program is currently used for mission planning called the Analytic Satellite Ephemeris Program (ASEP), which produces projected data for orbits that remain fairly close to Earth. Lunar and solar perturbations are taken into account in another program called GRAVE. This project is a revision of GRAVE which incorporates more flexible means of input for initial data, provides additional kinds of output information, and makes use of structured programming techniques to make the program more understandable and reliable. The computer program ORBIT was tested against tracking data for the first 313 days of operation of the CRRES satellite. A sample graph is given comparing the semi-major axis calculated by the program with the values supplied by NORAD. When calculated for points at which CRRES passes through the ascending node, the argument of perigee, the right ascension of the ascending node, and the mean anomaly all stay within about a degree of the corresponding values from NORAD; the inclination of the orbital plane is much closer. The program value of the eccentricity is in error by no more than 0.0002

Groundwater sapping channels: Summary of effects of experiments with varied stratigraphy

Experiments in the recirculating flume sapping box have modeled valley formation by groundwater sapping processes in a number of settings. The effects of the following parameters on sapping channel morphology were examined: surface slope; stratigraphic variations in permeability cohesion and dip; and structure of joints and dikes. These kinds of modeling experiments are particularly good for: testing concepts; developing a suite of distinctive morphologies and morphometries indicative of sapping; helping to relate process to morphology; and providing data necessary to assess the relative importance of runoff, sapping, and mass wasting processes on channel development. The observations from the flume systems can be used to help interpret features observed in terrestrial and Martian settings where sapping processes are thought to have played an important role in the development of valley networks

Cross-modal associations in synaesthesia: vowel colours in the ear of the beholder

Human speech conveys many forms of information, but for some exceptional individuals (synaesthetes), listening to speech sounds can automatically induce visual percepts such as colours. In this experiment, grapheme–colour synaesthetes and controls were asked to assign colours, or shades of grey, to different vowel sounds. We then investigated whether the acoustic content of these vowel sounds influenced participants’ colour and grey-shade choices. We found that both colour and grey-shade associations varied systematically with vowel changes. The colour effect was significant for both participant groups, but significantly stronger and more consistent for synaesthetes. Because not all vowel sounds that we used are “translatable” into graphemes, we conclude that acoustic–phonetic influences co-exist with established graphemic influences in the cross-modal correspondences of both synaesthetes and non-synaesthetes

Some clarifications on neural noise and sensory sensitivities in autism

Ward (this issue) has provided an elegant synthesis of the literature on the neural basis of individual differences in sensory sensitivity, and a useful proposed framework to guide future research. In this commentary I clarify some of the issues raised by Ward (this issue) surrounding neural noise and sensory sensitivities in autism

A high-fidelity satellite ephemeris program for Earth satellites in eccentric orbits

A program for mission planning called the Analytic Satellite Ephemeris Program (ASEP), produces projected data for orbits that remain fairly close to the Earth. ASEP does not take into account lunar and solar perturbations. These perturbations are accounted for in another program called GRAVE, which incorporates more flexible means of input for initial data, provides additional kinds of output information, and makes use of structural programming techniques to make the program more understandable and reliable. GRAVE was revised, and a new program called ORBIT was developed. It is divided into three major phases: initialization, integration, and output. Results of the program development are presented

Itʼs not what you Perceive itʼs the way that you Perceive it: Reflections on the Relationship Between Perceptual Appearance and Perceptual Aesthetics

For some time we have been interested in the measurement of visual appearance in medical applications. My previous presentations at CIE Expert Symposia have focused on the measurement and characterisation of dental fluorosis (i.e. white mottling on the teeth caused by the ingestion of too much fluoride in childhood) and post-surgical facial scarring ([1], [2]). In this presentation, however, I wish to broaden the focus to include other work from my laboratory on emotional aspects of colour processing and perceptual processing in autism. The issue I wish to address is the importance of verbal descriptions of our perceptions in understanding how to solve a variety of puzzles in perception, and how we might take this idea further in future research. Beginning with the work on fluorosis, the specific remit was to solve a practical problem: to what extent are teenagers bothered by having dental fluorosis? Previous research in public health dentistry had suggested that the white mottling on the teeth which can result from mild fluorosis was actually desirable to some teenagers because it made their teeth look whiter and more "sparkly". We addressed this question by producing digital simulations of different levels of fluorosis and embedding these simulations into a web-site. The key question we asked our (teenage) participants was: Is this appearance acceptable or not? Unsurprisingly, ratings of acceptability decreased with increasing fluorosis level, although this dependence went away at longer viewing distances (corresponding approximately to conversational distance). However, there was a strong baseline lack of tolerance for seeing anybody's teeth close-up which was problematic for our measurements. With the work on post-surgical facial scarring again the remit was a practical one: to quantify the difference in colour between scar and surrounding skin. Here again, we ran into difficult issues having collected the data. Scars are by no means homogeneously or consistently coloured and differ from surrounding skin in much more than just their colour. Another issue was that whilst individuals have no problem identifying the presence and extent of a scar it is much harder to do that in a meaningful way objectively. We were forced, therefore, into combining colour with texture measurement in order to attempt to characterise the scars automatically and also using panels of observers to draw around the scars on a touch screen to give us some idea of "ground truth" for our measurements. This work illustrates the usefulness of consensus coding in visual appearance research. In essence, the relevant adjective to describe our stimuli was "scarriness", which refers to that combination of texture, colour and 3D shape that we call scarring. However, in additional experiments we also asked participants to describe the scars in their own words. Whilst many colour, texture and 3D shape descriptors were used, other words like "delicate" and "tender" refer to more empathic possibilities, closer to the CIE's idea of "total" visual appearance ([3]). This leads us onto aesthetic aspects of visual perception. There is a growing body of literature on the aesthetic aspects of colour perception (see, [4]), which is beginning to be extended into visual appearance qualities such as texture (e.g. [5]). Participants have no difficulty in specifying not only what their "most preferred" colour is, but also which they find most pleasant, unpleasant, lively or calming. There is also a surprising consensus on which colours make us feel happy and sad. This fascinating area of research is also beginning to look carefully at individual differences, especially those between males and females, different cultures and different age groups. These groups can differ not only in what their responses are, but also in how much they are influenced by suggestion and prior exposure. Individuals on the autism spectrum have unusually strong sensory preferences ([6]). Indeed we have found that not only individuals with diagnoses of autism spectrum disorder (ASD) but also those with higher levels of autistic personality traits demonstrate marked differences in their responses to environmental sensory stimulation than those with few such traits. These difficulties can make some types of sensory stimulation intolerable. Whilst the list of stressors includes obvious things like flickering lights, fire alarms and chemical smells, these can also be such apparently innocuous things as brightly coloured objects, brushing past somebody in a supermarket and the smells of everyday foods. This survey of research might suggest that the idea of predicting perceptual responses is a hopeless task, complicated as it appears to be by the presence of these large individual differences. I would like to argue that a combination of careful characterisation of participant groups, using demographic data and personality questionnaires, and careful attention to the words people use to describe their sensory experiences, at least in the first instance, will lead to a greater ability to move forward in this field and thereby establish at least what the "average human" response will be in representative situations. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down

The St. James walkway study

Prior to the opening of the St James Walkway in 1981, David Simmons of the Department of Parks, Recreation and Tourism at Lincoln College, proposed a five year research programme to the New Zealand Walkways Commission. This proposal took advantage of the 1981 opening to initiate a longitudinal study which could identify any subsequent changes in use or use impacts on the Walkway. The general aims of this research were to: (i) Describe the user population of the Walkway and any changes to it over the study period; (ii) Describe the role played by the Walkway in the recreation life histories of users; and (iii) Identify any physical impacts from use that occurred following the opening of the new track. This paper presents a compilation, summary and assessment of data gathered from the research programme

Stimulation of bone growth with thrombin peptide derivatives

Disclosed is a method of stimulating bone growth at a site in a subject in need of osteoinduction. The method comprises the step of administering a therapeutically effective amount of an agonist of the non-proteolytically activated thrombin receptor to the site.Board of Regents, University of Texas Syste

Recreation demand estimation in New Zealand : An example of the Kaimanawa and Kaweka Forest Parks

This paper is in two parts. The first examines methods of recreation resource evaluation while the second uses an existing data base to discuss the potential applications of one such method in New Zealand. The specific objectives of the report are: 1. To discuss common economic methods of resource valuation, highlighting both their limitations, and potential contributions to the land use debate. 2. To demonstrate the use of one of these methods in valuing a New Zealand recreational resource

Geometric Limits of Julia Sets of Maps z^n + exp(2πiθ) as n → ∞

We show that the geometric limit as n → ∞ of the Julia sets J(Pn,c) for the maps Pn,c(z) = zn + c does not exist for almost every c on the unit circle. Furthermore, we show that there is always a subsequence along which the limit does exist and equals the unit circle