Showing papers by "Northampton Community College published in 1988"

Improved transparent boundary formulations for the elastic-wave equation

Abstract: It is shown that the paraxial approximations to the wave equation used by Clayton and Engquist can be improved upon, allowing more accurate finite-difference formulations at internal boundaries and corners, and formulations that are stable over a wider range of the parameters.

Social class and changes in weight-for-height between childhood and early adulthood.

Abstract: The changes in weight-for-height of those from different social class backgrounds have been examined in the 1958 longitudinal study. Social class differences in the prevalence of overweight and obesity were found to be negligible in childhood but marked by early adulthood, with a greater percentage of overweight and obesity in lower social classes. This different was three-fold among obese men and two-fold among obese women when respondents were classified on the basis of their own occupation. However, a longer term effect of early class backgrounds also emerged. Children from manual backgrounds were more likely to become overweight and obese young adults (7 per cent of those with average weight-for-height at age 7) compared with their non-manual contemporaries (3 per cent). Interestingly, they were also more likely to remain overweight or obese through to early adulthood. Methods preventing weight gain in early life, whilst poorly developed at present, need to ensure that approaches are relevant to young people with lower social class backgrounds.

First generation expert systems: a review of knowledge acquisition methodologies

Abstract: This paper reviews a wide range of knowledge acquisition techniques in the context of attempts to achieve a systematic methodology. These have been poorly documented by expert system builders, who are often inclined to overvalue textbooks and the ways experts themselves claim they solve problems. No one method has a universal advantage; each has some value. Techniques should be selected to suit the domain, the task, the expert and the knowledge engineer. Knowledge acquisition involves creating a conceptual model of expert knowledge and reasoning, from analysis of data elicited by these techniques. A survey of the literature indicates increasing emphasis on tools for knowledge acquisition, used directly by experts. Several projects currently directed towards providing a proper epistemological foundation for knowledge acquisition are discussed and compared. None has yet produced a complete epistemologically sound methodology; however, recognition of the need to create a conceptual model at the knowledge level (rather than the symbol level) is an important advance. An extensive bibliography is appended.

Who remains celibate

Abstract: Who are the men and women who are single in their mid-30s? This study which uses life history data for a British cohort born in 1946 shows that an important minority are handicapped and these adults are primarily cared for by their families in particular by elderly parents. Celibates tend to be more introverted ambitious and to have older marrying parents than their ever-married peers. Single women differ from single men. The women are more likely to be of higher ability to be graduates and to be in high status occupations while single men are more likely to be members of the lowest social class or unemployed. The great majority of single people live either with their parents or on their own. (authors)

Development, Validation and Application of Computer‐linked Knowledge Questionnaires in Diabetes Education

Abstract: Multiple choice questionnaires (MCQs) capable of being marked manually or by a newly developed optical mark reader, or by use of an inexpensive inter-active microcomputer system have been developed for the separate assessment of insulin-dependent and non-insulin-dependent patient knowledge Forty-six insulin-related and non-insulin-related multiple choice questions covering six main areas of knowledge were constructed for inclusion into draft questionnaires From the responses of a total of 180 completed questionnaires, piloted in 18 randomly selected clinics in 14 Regional Health Authorities in England, psychometric analysis was performed to determine reliability, discrimination coefficients, and facility indices Seventy-three per cent of insulin-dependent diabetic patients (IDDM) and 92% of non-insulin-dependent diabetic patients (NIDDM) MCQ correct options had facility indices within the acceptable range of 30 to 90% 82% IDDM and 93% NIDDM correct options had discrimination coefficients exceeding 02 Questionnaire reliability (internal consistency) using the Kudor-Richardson (KR20) formula was IDDM 087 and NIDDM 082 Evidence in support of the IDDM questionnaire's criterion validity was based on significant differences (p less than 005) identified between a number of knowledge area scores stratified according to HbA1 levels Prescriptive correction for screen display and automatic hard copy feedback was designed for both incorrect and omitted question options, providing both educational (patient) and analytical (clinic) documentation Both technical and psychometric properties of these knowledge assessment instruments should be acceptable for diabetic knowledge evaluation and instruction

The natural fluorescence of wool

Abstract: Wool may be excited by both mid-and near-u.v. radiation, emitting fluorescence. The extent of visible fluorescence depends on the origin of the wool and the degree of weathering, (the tips of the fibres being more fluorescent than the roots) and chemical modification. In particular oxidative treatments such as chlorination of shrink-resist procedures or peroxide bleaching processes increase the intensity of visible fluorescence but decrease the intensity of u.v. fluorescence (emission maximum at about 350 nm). It is proposed that the presence of these fluorescent chromophores in the fibre relates to the susceptibility of wool to yellow on exposure to light.

Decentralized determinantal assignment problem: fixed and almost fixed modes and zeros

Abstract: The decentralized determinantal assignment problem (DDAP) is defined as the unifying description for the study of pole and zero assignment problems under decentralized output, state feedback (DOF, DSF) and decentralized ‘squaring down’ (DSD), respectively. DDAP is reduced to a linear problem of zero assignment of polynomial combinants and a multilinear problem of restricted decomposability of multivectors. The decentralization characteristic (DC) and the decentralized polynomial Grassmann representative )D — ℝ[s] — GR) of DDAP are defined. The fixed zero polynomial of DDAP is then determined as the zero polynomial of D— ℝ[s]—GR. The canonical D—ℝ[s]—GR, (CD—R[s]—GR) and the decentralized Plucker matrix (DPM) of DDAP are introduced and necessary conditions for arbitrary assignment of the non-fixed zeros are given in terms of the DPM. The family of strongly zero non-assignable (SNA( systems is defined, and for such systems the notion of the fixed zero is extended to that of the ‘almost fixed zero’ (AFZ). An...

The behavioural treatment of verbal interaction skills following severe head injury: a single case study.

Abstract: This study reports the improvement of verbal interaction skills in a 27-year-old severely head-injured male who presented with an inappropriate attention-seeking circumlocutory conversational style. The patient was baselined on verbal response to three differing question forms, and then treated using combined cognitive behavioural methods on a daily sessional basis. Treatment resulted in a significant clinical change out of sessions, whilst the overall in-session improvement proved significant at the 005 level. Follow-up at 2 months indicated that the trend of improvement had continued beyond the treatment period.

The use of behavioral techniques in functional skills training after severe brain injury.

Abstract: This paper discusses the application of behavioral methods to functional skills training in the adult with severe brain damage. Four cases are described demonstrating the effectiveness of this type of intervention in teaching washing and dressing skills. Three patients had deficits arising from traumatic brain injury and one had continuing problems following herpes simplex encephalitis. Theoretical issues in adapting behavioral methods to the needs of such patients who have severe disorders of memory, attention, and motivation are discussed.

Prison officers' experience as a predictor of risk of attack: an analysis within the British prison system.

Abstract: Reports of inmate-officer assaults from a prison population of 1,000 males and covering an 18-month period were analysed in order to test the hypothesis that staff who either have little prison wor...

Application of Infrared Spectroscopy in Polymer Degradation

Abstract: Infrared (IR) spectroscopy has become a powerful tool for chemical and physicochemical characterization of polymeric materials. The growth in IR spectroscopy after 1945 was provided by development of reliable electronic amplifiers and radiation detectors. More recently new innovations have been made in this field with the commercial introduction of the computer-controlled Fourier transform infrared (FTIR) spectrophotometer.

Graphical interfaces for knowledge engineering: an overview of relevant literature

Abstract: Literature relevant to the design and development of graphical interfaces for knowledge-based systems is briefly reviewed and discussed. The efficiency of human-computer interaction depends to a large extent on the degree to which the human-machine interface can answer the user's cognitive needs and accurately support his or her natural cognitive processes and structures. Graphical interfaces can often be particularly suitable in this respect, especially in cases where the user's “natural idiom” is graphical. Illustrated examples are given of the way in which graphical interfaces have successfully been used in various fields with particular emphasis on their use in the field of knowledge-based systems. The paper ends with a brief discussion of possible future developments in the field of knowledge-based system interfaces and of the role that graphics might play in such developments.

Temperature dependence of the magnetization in ferromagnetic surfaces and overlayers

Abstract: The effect of softening of the exchange in a magnetic overlayer (surface) on the temperature dependence of the surface magnetization Ms(T) in the spin-wave regime is investigated. A recursion method for calculating the surface density of spin-wave states (DOS) is developed. It is applied to a magnetic overlayer of n atomic layers with softened exchange between the layers. The principal result obtained for an overlayer of any thickness between n = 1 and n = 20 is that the surface DOS and, therefore, the temperature dependence of the surface magnetization Ms(T) are determined by the exchange interactions in the overlayer (surface). The classical result of surface magnetism that Ms(T) follows the Bloch T 3 2 law but decreases twice as fast as in the bulk breaks down at temperatures as low as 1% of the Curie temperature Tc. Above this temperature, there is a rapid crossover to a second extended region of an effective T 3 2 law with a prefactor determined by the surface exchange. This second region of the T 3 2 law which extends up to temperatures T ≈ 0.4 Tc provides a perfect explanation for the observed Ms(T) which was determined recently by SPLEED for Ni40Fe40B20 surface and by Mossbauer spectroscopy for Fe(110) surface.

Treatment of mastitis and applicator therefor

Abstract: A method for treating mastitis which comprises the use of an infusion of an effective amount of (mon)oxychlorosene or sodium oxychlorosene in an aqueous carrier is disclosed. A mastitis treatment infusion applicator which comprises a body portion including a compartment containing a first material which is an aqueous carrier, a cap portion including a compartment containing a second material which is (mon)oxychlorosene or sodium oxchlorosene, a seal arranged on either the body or cap portion to separate the two compartments, and seal-breaking means arranged on either the cap or body portion respectively, wherein the cap and body portion are movable relative to one another between a first position in which the seal is intact and a second position in which the seal is broken and in which the materials in the two compartments may come into contact. At least the surfaces contacting the second material being fluorinated is also disclosed.

Approaches to the optimizing control problem

Abstract: The selection of the steady-state controls which enable a system to operate in an optimum manner is the optimizing control problem. An examination of direct and adaptive model-based approaches to this problem is made. In the direct approach, system measurements are used directly within an optimization procedure while, with the adaptive model-based techniques, an updated model is used for the optimization problem and the results of the model-based problem are applied to the system. Here, due to its recognized efficiency among established optimization algorithms, a conjugate direction method is adopted for the direct approach. For the model-based approach, two different techniques are described. A rationalized form of modified two-step method is presented along with a new method based on an approximate linear model. An assessment of the efficiency of the various methods is made through the simulation of a gas mixer system. The direct method is seen to be unrealistic while, for the system considered...

From water to wine: generating natural language text from today's applications programs

Abstract: In this paper we present a means of compensating for the semantic deficits of linguistically naive underlying application programs without compromising principled grammatical treatments in natural language generation. We present a method for building an interface from today's underlying application programs to the linguistic realization component Mumble-86. The goal of the paper is not to discuss how Mumble works, but to describe how one exploits its capabilities. We provide examples from current generation projects using Mumble as their linguistic component.

Situational complexity, systems modelling and methodology

Abstract: The aim of this paper is to consider primary attributes of complexity in situational contexts, particularly within the scope of systems modelling and methodology, and to ascertain which attributes ...

Right, left characteristic sequences and column, row minimal indices of a singular pencil

Abstract: For a general singular pencil sF — G∊ℝ m×n [s] the right, left characteristic sequences r(F, G), l(F, G) are defined and they are shown to be of the piecewise arithmetic progression type. The sets of column, row minimal indices ℐc(F, G), ℐr(F, G) are defined by a singular points analysis of r(F, G), ℐl(F, G) respectively. Thus, ℐc(F, G), ℐr(F, G) emerge as numerical invariants of the ordered pair (F, G) and they may be computed by rank tests on Toeplitz matrices defined on (F, G).

Experiments with the Bio-mittent lighting system for laying hens.

Abstract: 1. Two experiments are described in which a system of intermittent lighting (15 min light followed by 45 min dark for 15 h, then 15 min light, 30 min dark, 15 min light and 8 h dark) was applied to laying pullets from 37 to 72 weeks of age. A step-up lighting programme was used as a control treatment (8L:16D from 0 to 18 weeks, photoperiod increased by 20 min each week from 18 to 41 weeks, 16L:8D from 41 to 72 weeks of age). 2. Food consumption was reduced by about 5% when intermittent lighting was in use and by 3.8% for the period from 18 to 72 weeks. 3. Rate of lay and egg weight were similar for intermittent lighting and the control treatment, provided that protein content of the diet was adjusted to maintain an adequate amino acid intake. 4. In the second trial 2 stocks, 2 stocking densities confounded with 2 temperatures and 2 types of food trough were used. Each of these factors affected food intake and it was found that more food was saved by intermittent lighting when intake was high and less when it was low. The proportion saved was approximately 5%. 5. Mortality was slightly but not significantly lower in both experiments where intermittent lighting was used. This may indicate that caged pullets are under less stress when intermittent lighting is used.