bluuebunny/crossref_metadata_2025 huggingface dataset:
$\beta$-transformation, natural extension and invariant measure
Authors: BROWN GAVIN , YIN QINGHE
Published: July 2002

For $\beta>1$, consider the $\beta$-transformation $T_\beta$. When $\beta$ is an integer, the natural extension of $T_\beta$ can be represented explicitly as a map on the unit square with an invariant measure: the corresponding two-dimensional Lebesgue measure. We show that, under certain conditions on $\beta$, the natural extension is defined on a simply connected region and an invariant measure is a constant multiple of the Lebesgue measure.

We characterize those $\beta$ in terms of the $\beta$-expansion of one, and study the structure and size of the set of all such $\beta$.
Decay of geometry in the cubic family
Authors: ŚWIATEK GRZEGORZ , VARGAS EDSON
Published: July 2002

We study the box geometry of bi-modal maps. As has been expected, unlike in the unimodal case, there may be non-renormalizable mappings which do not show the decay of geometry. We provide an example. On the other hand, we come up with a natural pattern in which the critical orbits are closely intertwined, but the decay of geometry persists. All this is done in the context of a generally defined box inducing construction for bi-modal maps.
Framing Welfare Reform in Affluent Societies: Rendering Restructuring More Palatable?
Authors: Ross Fiona
Published: July 2002

This paper investigates the conditions under which political framing can render welfare restructuring more palatable. I start by asking two research questions. What are the necessary (albeit perhaps insufficient) conditions that allow leaders successfully to frame welfare reform? To what extent are these conditions evident across welfare regimes? I identify four variables that affect leaders' opportunities for framing social policy: (1) extant frames, (ii) actors, (iii) institutions and (iv) policy arena. After examining the four dominant types of frames found across affluent societies, I review the discursive politics surrounding The Personal Responsibility and Work Opportunity Reconciliation Act as a case where all four conditions for framing welfare reform coalesced.
Capping Entitlements: Budget Rules and the Food Stamp Program
Authors: King Ronald F.
Published: July 2002

The paper examines three forms of budgetary rule applied to the food stamp program — discretion, entitlement, and expenditure caps. The different budget rules are modeled with respect to their reversion point, the outcome that prevails by default if no cooperative agreement is reached. Hypotheses concerning budgetary politics and policy are derived from the models and tested using historical data from one arena over time. The case study is relevant to the broader problem of welfare spending. The dilemma is how to reconcile budget protection needed for the impoverished against the fragmentation and fluctuations of routine political conflict, and budget integration needed for democratic deliberation regarding the multiple tasks of government. Entitlement status insures program benefits for qualifying households, but it also carves off a portion of total outlays declared to be relatively uncontrollable, outside of the annual mechanisms of review and adjustment. Discretionary budgeting, by contrast, incorporates welfare within ordinary collective decision-making that establishes priorities across competing claimants for public funds, but it also risks making the poor in society victims of their own vulnerability. Expenditure caps have recently been proposed as a solution to the dilemma, allowing outlays to grow automatically up to a given threshold but requiring conscious choice if they threaten to breach the threshold. Caps are celebrated by proponents as an instrument fostering enhanced managerial oversight and reasonable expenditure control. This study of the food stamp program, however, reveals that caps are more likely to engender procedural complexities and substantive policy bias. Moreover, these are logical and foreseeable results, easily deduced from the models of budgetary rule.
Volunteerism among older people with arthritis
Authors: BARLOW JULIE , HAINSWORTH JENNY
Published: July 2002

Research attention has turned towards investigating the motivations and experiences of those who volunteer under conditions that benefit both giver and recipient. The purpose of this paper is to examine the motivation of 22 older volunteers as they embarked on training to become lay leaders of an arthritis self-management programme. Data were collected through semi-structured telephone interviews at two points in time, before training and six weeks after training. Volunteerism was motivated by three key needs: to fill the vocational void left by retirement, to feel a useful member of society by helping others and to find a peer group. These key motivations remained important throughout the six weeks of the study. The costs of volunteering were perceived as time, responsibility, invasion of social life, failure, anxiety, and the duration and intensity of training. Nonetheless, older volunteers valued finding a purpose, reported less pain and an increased desire to ‘get on with life'. Results suggest that volunteering in later life can help to offset losses associated with retirement and decline in health. Further research, incorporating standard measures of health status, is needed if the impact of volunteering on the health of this study population is to be more fully understood.
The role of grandparents when parents
part or die: some reflections on the
mythical decline of the extended family
Authors: THOMPSON PAUL
Published: July 2002

Belief that the extended family is in terminal decline has proved to be a
remarkably persistent myth. It is currently being revived as a result of recent
statistical trends. The belief has been closely connected to sociological enquiries
undertaken over the course of the century. The validity of the belief, and in
particular the significance of grandparents within the extended family, is
explored in two sets of life story interviews recently undertaken with adults in
Britain; one set are people in their thirties who had become step-children, and
the second set participants in a multi-generational study of social mobility. The
analysis addresses questions of contact after parental loss, sources of support
within the family, the involvement of grandparents, the importance of co-residence, conflict, emotional closeness and communication within a family.
From poorhouse overseer to production
manager: one hundred years of old-age
care in Sweden reflected in the
development of an occupation
Authors: TRYDEGÅRD GUN-BRITT
Published: July 2002

The aim of this article is to illustrate the changes in the Swedish system of old-age care during the 20th century by tracing and analysing the history of the
job of supervisor or manager of this care. The main sources that have been
researched are public and educational documents as well as articles from the
occupation's professional journal. Development through different periods is
described. During the first decades of the century, supervisors had a controlling
function in strictly disciplined poor-relief institutions. The period 1920–1950
was dominated by a strong belief in institution-based old-age care, and the
supervisor's role had a variety of profiles, e.g. matrons of home-like institutions,
geriatric nurses, and manageresses of increasing numbers of care-staff. The
decades 1950–1980, were characterised by expansion and new arenas, chiefly
the home-help services. In the 1990s, with a strained public economy, the
financial control became a central feature of the work of the managers.
Finally, some of the changes and trends are analysed and discussed.
Security dilemmas and the end of the Cold War
Authors: RALPH JASON
Published: July 2002

Alan Collins is to be congratulated for highlighting the role Gorbachev’s strategy of Graduated Reciprocation in Tension Reduction (GRIT) played in ending the military conflict between East and West. By offering an alternative view to the conservative opinion that America’s material strength forced the Soviets into submission, it suggests that statesmen caught in security dilemmas have real options and are not simply forced to compete for power. As a policy that fostered transparency which assisted the creation of security regimes, GRIT undoubtedly played a role in the way the military conflict ended. Yet the Cold War was not simply about the military balance. Collins’ account of this period is restricted by his bias towards state-centric and rationalist explanations of state behaviour. He underestimates the role ideology played in ending the Cold War and as such only offers half a Cold War story. The influence of the US during this period, as a cautious agent of liberal individualism, is completely ignored, yet, as this reply demonstrates, it is crucial to understanding the way the US reciprocated Soviet policies. Moreover, if ‘debate over what the Cold War was is part of the politics of deciding what the post-Cold War is’, the significance of this criticism is not merely academic. The implication of Collins’ unwritten assumption that state’s identities are egoistic is that a security community based on a common identity is impossible. The lesson that the Cold War, as opposed to the military conflict, only ended when a common identity based on liberal individualism was instituted, suggests that a transatlantic security community including Russia was and still is a possibility.
Getting into the groove?
Authors: Halstead Jill
Published: July 2002

Sexing the Groove: Popular Music and Gender.Edited by Sheila Whiteley. London and New York: Routeledge, 1997, 353 pp.

Sex, sexuality and articulations of gender are well-established components in the production and performance of popular music. Hence, Sexing the Groove, edited by Sheila Whiteley, is a very welcome addition to this vital and growing area of popular music studies and cultural theory more generally. The collection reflects the reality that studies of gender and sexuality in popular music are born of a hybrid lineage; accordingly the book approaches its subject from a range of disciplines such as sociology, cultural theory, media studies, sychology and musicology, and as such is a vibrant mix. Despite its relative diversity, the book's structure and progression is fluent and focused.
Music, radio and the record business in Zimbabwe today
Authors: SCANNELL PADDY
Published: July 2002

Radio and the recording business have, since the beginning of the last century, had a profound impact upon existing
musical life whenever and wherever they have decisively and irreversibly established themselves. Their arrival restructures and redefines the social relations of music in many aspects of its production, performance and reception. Radio
and recording technologies have had a significant impact on the livelihoods of all those who one way or another try
to make a living from music (composers, performers and - in Europe - publishers, for instance). Performance itself is
transformed as new norms are set in place which call for new levels of technique and interpretation. Finally the
conditions of musical reception are reconfigured and new `taste publics' emerge, potentially in conflict with each other,
as musical life is totalised into a new and complex unity.
Control of walking robots based on manipulation of the zero

moment point
Authors: Mitobe K. , Capi G. , Nasu Y.
Published: July 2002

In this paper, a

new application of the ZMP (Zero Moment Point) control law

is presented. The objective of this control method is to

obtain a smooth and soft motion based on a real-time

control. In the controller, the ZMP is treated as an

actuating signal. The coordinates of the robot body are fed

back to obtain its position. The proposed control method was

applied on two different biped robots, and its validity is

verified experimentally.
Complementary data fusion in vision-guide and control of robotic tracking
Authors: Chen Y.M. , Hsueh C.S.
Published: July 2002

We present a data fusion
control scheme for the hand-held camera of the SCORBOT-ER VII
robot arm for learning visual tracking and interception. The control
scheme consists of two modules: The first one generates candidate
actions to drive the end-effector as accurate as possible directly
above a moving target, so that the second module can
handily take over to intercept it. The desired camera-joint coordinate
mappings are generalized by Elman neural networks for a tracking
module. The intercept module then determines a suitable intercept trajectory
for the robot within the required conditions. The simulation results
support the claim that it could be successfully applied to
track and intercept a moving target.
Sagittal gait of a biped robot during the single support

phase. Part 2: optimal motion
Authors: Rostami Mostafa , Bessonnet Guy
Published: July 2002

The paper is aimed at generating optimal swing motions during the single-support phase of sagittal gait. Unlike the previous Part 1 which deals with passive motions, all joints of the biped are assumed to be active in the present Part 2. The final conditions specify an impactless heel-touch in order to avoid a destabilizing effect on the biped motion. As the biped is essentially submitted to gravity forces, the motion is generated by minimizing the joint actuating torques. Feasible motions are defined by state inequality constraints limiting joint motions, and defining foot clearance and obstacle avoidance during the swing. The optimization problem is dealt with using Pontryagin's Maximum Principle. A final two-point boundary value problem is solved by implementing a shooting method. The approach presented is illustrated by various numerical simulations applying to a seven-body planar biped which has four or five active joints during the swing phase.
Obstacle avoidance motion planning for mobile robots in a dynamic environment with moving obstacles
Authors: Wu Chia-Pin , Lee Tsu-Tian , Tsai Chau-Ren
Published: July 2002

A new real-time obstacle avoidance method for mobile robots has been
developed. This method, namely the vector-distance function method, permits
the detection of obstacles (both moving and stationary) and generates a path
that can avoid collisions. The proposed approach expresses the distance
information in a vector form. Then the notion of weighting is introduced to
describe relationship between sensors of mobile robots and the target to be
reached. Furthermore, R-mode, L-mode and T-mode are introduced to generate a
safe path for the mobile robot in a dynamic environment filled with both
stationary and moving obstacles. The algorithm can deal with a complicated
obstacle environment, such as multiple concave and convex obstacles.
Simulation results are included to demonstrate the applicability and
effectiveness of the developed algorithm.
Gait Synthesis for a biped robot
Authors: Shih Ching-Long
Published: July 2002

In this paper, the realization of biped walking on even floor,
sloping surfaces, and stairs is studied. The motion trajectories for the
biped's body and its two feet are modeled by piecewise cubic polynomials.
The main features of the biped robot include two variable-length legs and
a moving weight which can be positioned side-to-side for balance. The
contribution of this paper is gait synthesis and is
experimental verification.
Regeneration patterns of Cedrela lilloi (Meliaceae) in northwestern Argentina subtropical montane forests
Authors: Grau Hector Ricardo
Published: July 2002

All individuals of Cedrela lilloi (a valuable timber species of Meliaceae) > 4 cm DBH were sampled in three rectangular plots (c. 15 000 m2 each) in northwestern Argentina subtropical montane forests between 850 and 1350 m. Regeneration dynamics of C. lilloi was characterized by testing two hypotheses: (i) C. lilloi has a gap-phase regeneration mode, which implies a negative exponential size/age distribution at forest stand scale, growth releases due to canopy openings, and juvenile trees clumped at spatial scales of treefall gaps. (ii) There is a negative spatial association between adults and juveniles of C. lilloi which could be caused by density dependent mortality. Despite differences in age structure, diameter distribution approximated a negative exponential curve at all sites. Radial growth, measured as tree-ring widths, averaged between 2 and 4 mm y−1 which is comparable to fast growing tropical species in mature forests. Aggregation of juveniles peaked at radial distances of 8 to 15 m. Size structure, growth and spatial patterns of juveniles support the first hypothesis. In support of the second hypothesis, juveniles showed a negative spatial association with conspecific mature trees at spatial scales of less than 20 m. The Janzen–Connell model of density-dependence is one potential explanation for this pattern. Although regeneration and growth patterns of C. lilloi suggest a potential for sustainable management based on small-scale gaps, spatial dynamics at stand-scale need to be considered to ensure the regeneration of mature trees.
The gender division of labour: the case of Tuscan smallholders
Authors: EMIGH REBECCA JEAN
Published: July 2002

What explains the gender division of labour in preindustrial economies?
Although men and women frequently do different types of labour in any
given society, men's and women's tasks vary considerably across different
societies. In some societies, women engaged in trade and agriculture (in
parts of Africa, for example); though these were men's duties in others (in
parts of Europe, for example). At the same time, European historians
discovered that women often engaged in tasks, such as agricultural labour
and commerce, that were often assumed to be the domain of men, again
suggesting a wide variation in the gender division of labour. Understanding
the division of labour in preindustrial economies is important,
because these historical cases often serve as implicit or explicit referents
for understanding how much – or how little – has changed in
contemporary societies.

A number of excellent works, such as those by Barbara Hanawalt and
Martha Howell, have explored women's roles in the economy. However,
often missing from treatments that focus on women's history is an analysis
of the gender division of labour, that is, an explicit comparison of men's
and women's activities. Undoubtedly, such a comparison is hampered by
the difficulties of finding documentary sources that provide the
appropriate type of evidence.

This article takes up this task in a particular way, by examining single-person households, composed of either males or females in fifteenth-century rural Tuscany. This empirical evidence is useful for several
reasons. First, from an analytical perspective, it makes it possible to
compare explicitly the activities of men and women who are in an identical
position, that is, living alone. Second, as I discuss below, the documentary
record from this period makes it possible to provide the evidence for this
comparison. Third, this evidence provides historical information on a
relatively under-researched group, rural widows and widowers. For
example, there is generally more information available for Florentine
women than for female rural inhabitants. Furthermore, little research
explicitly compares men's and women's tasks to examine the gender
division of labour. Although Piccinni and Mazzi and Raveggi provide
much information about women's duties and activities in rural Tuscany,
their work does not directly address the gender division of labour. While
the archival evidence presented below cannot explain the division of
labour at all points in individuals' life courses, it does provide explicitly
comparative information about men and women.
Knowledge level modelling: concepts and terminology
Authors: USCHOLD MIKE
Published: July 2002

We address the problem of highly varied and inconsistent usage of terms by the knowledge technology community in the area of knowledge-level modelling. It is arguably difficult or impossible for any standard set of terms and definitions to be agreed on. However, de facto standard usage is already emerging within and across certain segments of the community. This is very difficult to see, however, especially for newcomers to the field. It is the goal of this paper to identify and reflect the most common usage of terms as currently found in the literature. To this end, we introduce and define the concept of a knowledge level model, comparing how the term is used today with Newell's original usage. We distinguish two major types of knowledge level model: ontologies and problem solving models. We describe what an ontology is, what they may be used for and how they are represented. We distinguish various kinds of ontologies and define a number of additional related concepts. We describe what is meant by a problem solving model, what they are used for, and attempt to clarify some terminological confusion that exists in the literature. We define what is meant by the term ‘problem’, and some common notions used to characterise and represent problems. We introduce and describe the ideas of tasks, problem solving methods and a variety of other important related concepts.
LIFTING PRACTICE: TEACHERS AS RESEARCHERS IN THE LANGUAGE
CLASSROOM. Louise M. Jansen & Anthony J. Liddicoat (Eds.). Canberra:
Language Australia, 1998. Pp. 110. A$19.80 paper.
Authors: Becker Claudia A.
Published: July 2002

Jansen and Liddicoat's volume on teachers as researchers in the FL/SL classroom
is an invaluable contribution to the complex and complicated issue of assessing formal language
learning environments (i.e., classrooms). The purpose is to provide “an overview of the
philosophy which underlies the inclusion of research as a central part of an in-service professional
development program” (p. 1) as well as to “give examples of the scope and
potential for research conducted by teachers” (ibid.).
Constraints on the computational component vs. grammar in the lexicon: a discussion of Bates & Goodman
Authors: GRINSTEAD JOHN
Published: July 2002

In The emergence of language, it is argued that much of what generative
linguistics has characterized as ‘rules’ in fact can be derived from domain-
general cognitive mechanisms. One example of this perspective is Bates &
Goodman's contribution ‘On the emergence of grammar in the lexicon’,
which Sabbagh & Gelman say offers ‘…a series of compelling arguments
detailing how development and early acquisition shape the subsequent
acquisition of new information.’ The thrust of the argument presented by
Bates & Goodman is that there is no need to posit the existence of an
independent grammar domain, because grammar can be reduced to the
lexicon, which in Bates & Goodman's account, can be acquired using general
purpose mechanisms. One of several major arguments in favour of this
position presented by the authors is that grammar and vocabulary grow at
the same rates in child speech. Thus, the authors argue that the development
of the lexicon and grammar correlate because there is no grammar outside of
the lexicon.
Emergence is what?
Authors: SABBAGH MARK A. , GELMAN SUSAN A.
Published: July 2002

The commentaries provide a thoughtful range of responses that reflect the
existing theoretical diversity concerning explanations of language development.
Below we clarify and amplify a few points from our original review
that appeared to have been unclear.
Children's judgements about intentionally and unintentionally broken promises
Authors: MAAS FAY K. , ABBEDUTO LEONARD
Published: July 2002

Astington (1988) found that seven- to nine-year-olds often fail to
distinguish between promises and predictions when judging the utterances
of characters in simple stories. Instead, these children attend only
to the outcome of the story (i.e. whether the promised event occurred)
when deciding whether a promise has been made and, to a lesser extent,
when deciding whether the speaker is responsible for the outcome. The
purpose of the present study was to examine whether seven- to nine-year-olds
(a) vary their judgements of responsibility according to the
reason that the promised action was not completed, and (b) recognize
that an unfulfilled promise is a promise regardless of whether the
speaker's failure is unavoidable or intentional. Seven-year-olds, nine-year-olds,
and adults were asked to make promise and responsibility
judgements for two story types: stories in which the promiser intentionally
failed to fulfil his or her promise and stories in which an
unforeseen event prevented the promiser from fulfilling the promise.
Participants at all ages assigned responsibility correctly across both story
types. In making promise judgements, however, the seven-year-olds'
decisions about promises reflected a misguided attention to the outcome
of a promise or the obstacle to its fulfilment. The nine-year-olds
recognized that an unfulfilled promise is a promise but only when there
was a clear reason for the speaker's failure to fulfil his or her obligation.
We suggest that children consider only sincere promises to be instances
of promising and make inferences about speaker sincerity by looking to
external factors in the communicative context.
Anxious Futures: Magpie2 and ‘New Generationalism’ in Australian Youth-Specific Theatre
Authors: Hunter Mary Ann
Published: July 2002

The field of contemporary youth-specific theatre in Australia is one of change and, in some cases, anxiety. While Drama Studies continue to grow in popularity in schools, previously conventional developmental paradigms have become less mandatory for theatre for, by, and about young people outside the school context. Instead, ‘new generation’ approaches in youth-specific performance are placing greater value on young people's own preferences in cultural activity. Yet this development is being tempered and further complicated by a cultural ‘generationalism’, particularly in larger arts organizations as the youth sector becomes a more integral part of marketing strategies for the future. The resulting ambiguity in the representation, value, and positioning of young people and youth-specific arts in Australia's theatre industry is considered by focusing on Magpie2, a former youth-specific company attached to the State Theatre Company of South Australia. Magpie2 ceased operation in 1998 after experimenting with a ‘new generation’ approach to theatre for young people in the State Theatre realm. Both the artistic policy of Magpie2 Director, Benedict Andrews, and the critical reception of his two productions in 1997, Future Tense and Features of Blown Youth, demonstrate how competing systems of cultural value characterize the field of youth-specific theatre in Australia.
Theatre and Performance at a Time of Shifting Disciplines
Authors: Carlson Marvin
Published: July 2002

The boundaries of theatre as an academic discipline have never been particularly clear, and its relationship to other disciplines has been the focus of constant struggle and negotiation. This essay traces that negotiation, focusing upon its process in American universities. Competing with literature departments for the study of dramatic texts, American theatre departments drew their own new disciplinary model, based primarily on German Theaterwissenschaft, with emphasis upon the staging history and historical context of dramatic texts. More recently such emerging fields as performance studies and cultural studies have sought to transcend such traditional disciplinary boundaries. Despite some resistance from existing academic and publishing structures, the trend towards the breaking down of these traditional boundaries seems clear. Our academic culture seems headed towards a considerably more fluid organization of its materials of study than the traditional organization into fairly discrete disciplines could offer.
Increasing the Spatial Limits of LADGPS Using Stratospheric Platforms
Authors: Boiero G. , Dovis F. , Mulassano P. , Mondin M.
Published: July 2002

This paper presents the preliminary study of a stratospheric segment within a satellite
navigation system of present and future generation (GPS and Galileo) implemented by
means of High Altitude and Very long Endurance (HAVE) platforms. The paper discusses
a possible scenario in which the main features of the HAVE platform are exploited to define
an innovative Aerial-Based Augmentation System (ABAS) for the provision of differential
services. This particular local segment improves the provision of a differential navigation
service. It is suited to the broadcasting of differential corrections in critical areas such as
mountainous and sea regions where, to guarantee wide coverage, a large number of
terrestrial reference stations would otherwise be required. The study includes a description
of the proposed DGPS augmentation system, and a discussion of the system architecture and
expected performance.
Removal of an Ambiguity from the Maritime Collision Regulations
Authors: Cooper R. W.
Published: July 2002

One of the essentials of the Collision Regulations is that they should, so far as
possible, eliminate doubt in the minds of navigators using them. In recent years, an
amendment has introduced a serious, dangerous doubt.
Pilot Preferences on Vector Moving-Map Displays
Authors: Lohrenz Maura C. , Myrick Stephanie A. , Trenchard Michael E. , Ruffner John W. , Cohan Tyrus
Published: July 2002

Vector map databases offer the potential for customised cockpit moving-map displays, in
which user-specified cartographic features can be layered to meet mission requirements. The
disadvantage of vector moving-maps is the potential for increased user workload. In 1995,
the Naval Research Laboratory and the Naval Air Weapons Center jointly performed a
preference study, during which aircrew viewed demonstrations of prototype moving-map
displays and responded to a detailed questionnaire concerning the usefulness of each display.
This paper summarises aircrew interviews from that study pertaining to both vector moving-map displays and vector feature overlays, including Height-Above-Threshold (HAT), threat
rings, and Clear Line-of-Sight (CLOS).
Global tropical forest area measurements derived from coarse resolution satellite imagery: a comparison with other approaches
Authors: MAYAUX PHILIPPE , ACHARD FRÉDÉRIC , MALINGREAU JEAN-PAUL
Published: July 2002

Definition of appropriate tropical forest policies must be supported by better information about forest distribution. New information technologies make possible the development of advanced systems which can accurately report on tropical forest area issues. The European Commission TREES (Tropical Ecosystem Environment observation by Satellite) project has produced a consistent map of the humid tropical forest cover based on 1 km resolution satellite data. This base-line reference information can be further calibrated using a sample of high-resolution data, in order to produce accurate forest area estimates. There is good general agreement with other pantropical inventories (Food & Agriculture Organization of the United Nations Forest Resources Assessment 90, World Conservation Union Conservation Atlas of Tropical Forests, National Aeronautics & Space Administration [USA] Landsat Pathfinder) using different approaches (compilation of existing data, statistical sampling, exhaustive survey with satellite data). However, for some countries, large differences appear among the assessments. Discrepancies arising from this comparison are here analysed in terms of limitations associated with each approach and they are generally associated with differences in forest definition, data source and processing methodology. According to the different inventories, the total area of closed tropical forest is estimated at 1090–1220 million hectares with the following continental distribution: 185–215 million hectares in Africa, 235–275 million hectares in Asia, and 670–730 million hectares in Latin America. A proposal for improving the current state of forest statistics by combining the contribution of the various methods under review is made.
Computers and learning
Authors: PURVES WILLIAM K. , WILLIAMS MARY E.
Published: July 2002

The important questions for instructors to address
concern what skills the student is to learn and how the
student is to be motivated to acquire those skills. Questions
about simulations, graphics tools, and the like are unimportant
until the first two questions have been answered adequately.
We discuss the role of explanation by students and describe
a mechanism for motivating students to learn.
Stimulating appropriate uses of simulation in design
Authors: ROSENBERG JAMES J.
Published: July 2002

This article addresses the issue of educating undergraduate
engineering students in the appropriate use of computer
simulation in the design process. The premise that poorly
designed assignments involving simulation can actually
impair understanding is addressed. A set of goals for simulation-based
exercises is suggested, and some tactics for meeting these
goals are introduced. Finally, a specific example of a
half-term assignment that is used to meet these goals is
provided for illustration.
A classification and constraint-based framework for configuration
Authors: MAILHARRO DANIEL
Published: July 2002

One of the main difficulties with configuration
problem solving lies in the representation of the domain
knowledge because many different aspects, such as taxonomy,
topology, constraints, resource balancing, component generation,
etc., have to be captured in a single model. This model
must be expressive, declarative, and structured enough
to be easy to maintain and to be easily used by many different
kind of reasoning algorithms. This paper presents a new
framework where a configuration problem is considered both
as a classification problem and as a constraint satisfaction
problem (CSP). Our approach deeply blends concepts from
the CSP and object-oriented paradigms to adopt the strengths
of both. We expose how we have integrated taxonomic reasoning
in the constraint programming schema. We also introduce
new constrained variables with nonfinite domains to deal
with the fact that the set of components is previously
unknown and is constructed during the search for solution.
Our work strongly focuses on the representation and the
structuring of the domain knowledge, because the most common
drawback of previous works is the difficulty to maintain
the knowledge base that is due to a lack of structure and
expressiveness of the knowledge representation model. The
main contribution of our work is to provide an object-oriented
model completely integrated in the CSP schema, with inheritance
and classification mechanisms, and with specific arc consistency
algorithms.
An aggregate weld product model for the early design stages
Authors: YAO Z. , BRADLEY H.D. , MAROPOULOS P.G.
Published: July 2002

Existing product models do not adequately support
the modelling of weld products during the early design
stages. A newly developed aggregate product model for welding
is introduced, which forms part of CAPABLE, a concurrent
engineering toolkit for machining and welding. This product
model supports the representation of the design at multiple
levels of detail and allows the rapid modelling of alternative
designs where solid model representation is inappropriate.
The potential applications of the aggregate product model
in weld product design, such as the integration of joint
design and weldability assessment, are discussed using
simple examples. The design of weld products must consider
process-dependent properties including geometry, materials
combinations, and weld joint characteristics to arrive
at a near-optimal configuration. The object-oriented and
feature-based model structure of CAPABLE enhances the design
process by the automatic generation of compatible options
and allows rapid design evaluation. The aggregate product
model provides the input data necessary for tasks like
process selection, optimization, process sequencing, fixture
design and welding orientation selection. The main advantage
of this product model over traditional CAD environments
is that planning of the welding and fabrication operations
can start during the conceptual and embodiment stages of
the design process, thus ensuring the concurrency of design
and planning tasks and resulting in product and process
improvement and cost reduction.
Hepatitis B outbreak at Glenochil prison during January to June 1993
Authors: HUTCHINSON S. J. , GOLDBERG D. J. , GORE S. M. , CAMERON S. , McGREGOR J. , McMENAMIN J. , McGAVIGAN J.
Published: July 2002

This data linkage study examined the extent of hepatitis B transmission
and co-infection with
HIV among 636 former inmates of Glenochil prison, Scotland, during an outbreak
of
bloodborne diseases in 1993 which was related to needle sharing. Eleven
inmates imprisoned
during the first half of 1993 presented with hepatitis B infection, of
whom co-infection with
HIV was detected in six. Based on dates of test results in relation to
time of imprisonment,
seven definitely acquired their hepatitis B infection within the
prison. Only two infections were
reported to Scotland's hepatitis B register and neither could be
prison-linked. This outbreak of
hepatitis B is the first of its kind to be reported but not the
first to have occurred. It not only
highlights the urgency for measures to prevent further spread of infection
among prisoners but
also illustrates the need for comprehensive surveillance of hepatitis B
infection, and the need
for a protocol on how to manage such outbreaks and on how to establish
the extent of
transmissions when acute hepatitis B occurs in prison.
Epidemiology of Streptococcus pneumoniae infection in
Malaysia
Authors: ROHANI M. Y. , RAUDZAH A. , NG A. J. , NG P. P. , ZAIDATUL A. A. R. , ASMAH I. , MURTAZA M. , PARASAKTHY N. , MOHD YASMIN M. Y. , CHEONG Y. M.
Published: July 2002

During a 1-year period from October 1995 to September 1996, 273
isolations of Streptococcus
pneumoniae were made from various types of clinical specimens. The
majority of the isolates
(39·2%) were from sputum whilst 27·5% were from blood, CSF
and other body fluids. The
organism was isolated from patients of all age groups, 31·1% from
children aged 10 years and
below, 64·7% of which come from children aged 2 years or below.
The majority of the isolates
belong to serotypes 1, 6B, 19B, 19F and 23F. Serotypes 1 and 19B were the
most common
serotypes associated with invasive infection. About 71·9% of the
invasive infections were due
to serotypes included in the available 23 valent polysaccharide vaccine.
The rates of resistance
to penicillin and erythromycin were 7·0 and 1·1% respectively.
Our findings show that the
serotypes of S. pneumoniae causing most invasive infections in
Malaysia are similar to those in
other parts of the world and the available vaccine may have a useful role
in this population.
The relationship between ocular toxoplasmosis and levels of
specific toxoplasma antibodies
Authors: CHAPMAN D. J. , ASHBURN D. , OGSTON S. A. , HO-YEN D. O.
Published: July 2002

The relationship between ocular toxoplasmosis and levels of toxoplasma specific antibodies was
examined in 195 patients. Using clinical information collected by questionnaires, patients were
divided into: 97 with ocular toxoplasmosis (group 1) and 98 with ocular lesions not due to
toxoplasma (group 2). The geometric mean of dye test titres (±S.D. natural log titre) in group 1 was 53·2 (±0·95) compared with 24·6
(±1·11) in group 2 (P<0·001). Young females tended
to have more active lesions compared with young males (P<0·05). There was an age-dependent difference in dye test titres between the groups (P<0·001). Group 1 showed a
decline in titre with age compared with an increase in group 2. Ocular toxoplasmosis was
diagnosed most frequently among 21–30 year olds. More group 1 patients had dye test titres [ges ]65 iu/ml than group 2 (P<0·05). Dye test titres [ges ]65 iu/ml support a diagnosis of ocular
toxoplasmosis whereas lower titres suggest other causes for eye lesions.
Molecular typing of Escherichia coli O157[ratio ]H7 (H−) isolates
from cattle in Japan
Authors: AKIBA M. , MASUDA T. , SAMESHIMA T. , KATSUDA K. , NAKAZAWA M.
Published: July 2002

A total of 77 Escherichia coli O157[ratio ]H7 (H−) isolates from cattle in Japan were investigated by
molecular biological methods. Most of these isolates (43 isolates) possessed the stx2 gene, but
not stx1. Fifteen bacteriophage types and 50 pulsed-field gel electrophoresis (PFGE) profiles
were observed. One isolate was indistinguishable from the human outbreak strain by these
methods. This indicates that cattle must be considered as a possible source of human E. coli
O157[ratio ]H7 infection in Japan.
Levels of virulence are not determined by genomic lineage of
Salmonella enterica serotype Enteritidis strains
Authors: OLSEN J. E. , TIAINEN T. , BROWN D. J.
Published: July 2002

Mouse virulence and the ability to adhere to, and invade cultured MDCK cells were
investigated in 38 phage type reference strains of Salmonella enterica serotype Enteritidis and
correlated with genomic lineage. The genomic lineage of 11 of the strains was determined in
the present study; one IS200 and one ribotype pattern that had not been reported previously
were observed. Log c.f.u. in the spleen 10 days post intraperitoneal (i.p.) infection with 3×103
bacteria (logVC10) varied between 2·9 and 8·7. The reference strains of PT7 and PT23 were
found to be semi-rough and were of low virulence. All other strains possessed smooth LPS.
Within each of the two major clonal lines, as well as among phage types outside these, both
highly virulent and moderate to low virulent strains were present. While all strains of PT1, PT2
and PT8 were highly virulent, low virulent strains were detected in PT4 and PT13. The ability
to adhere to, and invade MDCK cells varied between phage types (adherence between 13 and
61% of the inocula and invasion between 4 and 151% of the adherent cells). The results of
the cell culture experiments did not correlate with the results of mouse virulence tests. No
correlation between clonal lineage and virulence was found within S. Enteritidis. It seems most
likely that some strains have lost some of the essential factors enabling this serotype to cause
successful systemic infection.
Rhythmical variation in Hungarian
Authors: Varga László
Published: July 2002

The kinds of rhythmical variation I will examine in this paper
can be
observed in some double-accented Hungarian words, and can be
exemplified by the changes that the stressing of the numeric compound
′tizen′három ‘thirteen’
may undergo when it is embedded in phrases.
The stressing of this word may become tizen′három
in the phrase ′pont
tizen′három ‘exactly thirteen’
and ′ tizen′három in the phrase
′ tizen′három
′pont ‘thirteen points’. The two processes,
however, are not quite
symmetrical in their range of application; the first kind of change occurs
in only a subset of the words affected by the second kind. The symbol ′
in the examples represents a pitch accent on the syllable whose
orthographic form it precedes.

These changes are the Hungarian counterparts of the two kinds of
rhythmical variation in English, manifested, for instance, by the different
realisations of the word ′thir′teen,
when it is embedded in phrases like
′thirteen ′points or ′just
thir′teen. However, while rhythmical variation in
English is extremely widespread, in Hungarian it is restricted to certain
classes of words. Besides, rhythmical variation in English lacks the
asymmetry between the two processes; both kinds of change affect the
same set of words.

This article concentrates on rhythmical variation in Hungarian and on
the implications of this variation for metrical theory.
The relationship between attachment cognitions and psychological adjustment in late adolescent women
Authors: BURGE DORLI , HAMMEN CONSTANCE , DAVILA JOANNE , DALEY SHANNON E. , PALEY BLAIR , LINDBERG NANGEL , HERZBERG DAVID , RUDOLPH KAREN D.
Published: July 2002

This longitudinal study of 137 female high school seniors investigated the
relationship of attachment cognitions, current psychological functioning, and psychological
functioning 12 months later. Attachment cognitions, assessed with the Revised Adult Attachment
Scale and the Inventory of Parent and Peer Attachment, were significantly associated with current
symptomatology. The Revised Adult Attachment Scale, in interaction with initial
symptomatology, predicted depression, substance abuse, eating disorders, and personality
disorders 12 months later. The Inventory of Parent and Peer Attachment parent subscales
predicted eating disorder and personality disorder symptomatology, whereas the peer subscales
predicted substance abuse, eating disorder, and personality disorder symptomatology.
The Preschool Assessment of Attachment: Construct validity in a sample of depressed and

nondepressed families
Authors: TETI DOUGLAS M. , GELFAND DONNA M.
Published: July 2002

Construct validity of the newly developed Preschool Assessment of Attachment (PAA) was

examined in a sample of depressed and nondepressed mothers and their preschoolers, focusing

on attachment related differences in children's general caregiving environments, maternal

psychosocial functioning, and child behavior during interactions with mother. Mothers of secure

children were more emotionally and verbally responsive to their children than were mothers of

insecure children, and secure children were emotionally more positive to their mothers than were

insecure children. Mothers of secure children also reported higher levels of social supports than

did mothers of insecure children. Finally, dyads with children who lacked unitary, coherent

attachment strategies (i.e., anxious depressed, defended/coercive, and insecure other)

showed the worst functioning in all domains relative to all other attachment groups. Similar but

slightly less robust findings were obtained with socioeconomic variables statistically controlled.

These results lend support to the PAA as a valid system for the conceptualization and

measurement of quality of attachment among preschoolers. Future research applications with the

PAA are discussed.
Chemically induced grain boundary dynamics,
forced motion by curvature,
and the appearance of double seams
Authors: FIFE PAUL C. , WANG XIAO-PING
Published: July 2002

The free boundary model of diffusion-induced grain boundary motion derived in Cahn et
al. [3], Fife et al. [6] and Cahn & Penrose [4] is extended, in the case of thin metallic films, to
account for bidirectional motion, together with the appearance of S-shapes and double seam
configurations. These are often observed in the laboratory. Computer simulations based on
the extended model are given to illustrate these and other features of bidirectional motion.
More generally, the extension accounts for the motion of grain boundaries whose traces on
the film's surface are curved. The new free boundary model is one of forced motion by
curvature, the forcing term possibly changing sign due to the bidirectionality. The thin film
model is derived systematically under explicit assumptions, and an adjustment for grooving
is included.
Diabetes in the elderly
Authors: Knight Paul V , McKenzie Alan
Published: July 2002

Diabetes mellitus is a common and expensive condition which is reported to be responsible for as much as 4-5% of national health care expenditure in developing countries. It is a disease of some antiquity, although the predominant clinical presentation is not that which was described by Aretaeus in the second century AD ('a melting down of the flesh and limbs into urine').
Bereavement and mental health in the elderly
Authors: Parkes Colin Murray
Published: July 2002

Because women die at an older age than men, and marry men older than themselves, widows outnumber widowers and the average woman can expect to survive her husband by five to six years. In fact, widows make up a substantial proportion of the elderly population. In this paper the current state of our knowledge of the reaction to bereavement in the elderly will be reviewed and its implications for the provision of services considered.