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Time Dimension (time + dimension)

Distribution by Scientific Domains

Business, Economics, Finance and Accounting	37%
Information Science and Computing	25%

Selected Abstracts

Space-Time Hierarchical Radiosity with Clustering and Higher-Order Wavelets

COMPUTER GRAPHICS FORUM, Issue 2 2004
Cyrille Damez
Abstract We address in this paper the issue of computing diffuse global illumination solutions for animation sequences. The principal difficulties lie in the computational complexity of global illumination, emphasized by the movement of objects and the large number of frames to compute, as well as the potential for creating temporal discontinuities in the illumination, a particularly noticeable artifact. We demonstrate how space-time hierarchical radiosity, i.e. the application to the time dimension of a hierarchical decomposition algorithm, can be effectively used to obtain smooth animations: first by proposing the integration of spatial clustering in a space-time hierarchy; second, by using a higher-order wavelet basis adapted for the temporal dimension. The resulting algorithm is capable of creating time-dependent radiosity solutions efficiently. [source]

A public-health perspective on violence

ACTA PSYCHIATRICA SCANDINAVICA, Issue 2002
K. Melinder
Objective:, To describe how specific theories and methods used in public health, especially regarding injuries, are related to violence. Method:, Theories and preventive work in injury research (above accidents) are presented and related to violence. Results: Registration of injuries and an interest in the environment are seen as specific for injuries. In prevention there is a focus on community work and the concept of ,a safe community' has been developed. Haddon's matrix offers a foundation for theoretical injury research. It is formed by cross-tabulating the trichotomy of host-agent-environment against a time dimension. Conclusion:, One practical and one theoretical model on how violence might be seen as an injury have been demonstrated. No clear evaluation has been made of the practical model up to now. The theoretical model has the advantage that the model makes it easier to get a more comprehensive picture of how different factors influence violence. [source]

How issues get framed and reframed when different communities meet: a multi-level analysis of a collaborative soil conservation initiative in the Ecuadorian Andes

JOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 3 2004
Art Dewulf
Abstract Drawing on qualitative data from a longitudinal case study of a collaborative soil conservation initiative in southern Ecuador, we study how multiple actors, including university experts, development organizations and local communities, make sense of the issues from different perspectives through the process of issue framing. Starting from an analysis of the actors' usual issue frames, we point out their differences in selecting aspects, connecting them and drawing boundaries around the issues. Bringing in the time dimension leads us to consider how changing patterns of actor involvement and evolving frame configurations mutually influence each other. In a third step, we zoom in on the here-and-now level of ongoing interaction using discourse analysis, outlining an interactive, communicative and discursive approach to dealing with differences in issue framing. We identify various ways of dealing with these differences and argue that approaching them constructively by tuning the different frames into a mutually acceptable configuration is an important challenge for any attempt at integrated management of natural resources. Copyright © 2004 John Wiley & Sons, Ltd. [source]

The sourcing of technological knowledge: distributed innovation processes and dynamic change

R & D MANAGEMENT, Issue 4 2003
Jeremy Howells
This paper outlines the knowledge and technology sourcing practices of a range of key firms and organisations across the UK based on primary research, and analyses the key factors related to managing the technological knowledge boundaries of the firm. In particular, the paper considers the dynamic dimension considerations to such issues. As such it outlines important differences between short and long time horizons, before analysing in more detail some of the implications for firms of technological change over the long term. The paper seeks to highlight the importance of the time dimension in helping to explain why and how firms source technological knowledge externally and how they align their sourcing activities to their strategies associated with developing current and future capabilities. [source]

Business Cycle Volatility, Uncertainty and Long-run Growth

THE MANCHESTER SCHOOL, Issue 5 2001
Richard Kneller
Using data for 24 OECD economies from 1961 to 1997 we investigate whether the empirical relationship between business cycle volatility and long-run growth is positive, as Blackburn (Economic Journal, Vol. 109, No. 1 (1999), pp. 67,77) suggests, or negative, the view of the UK and other governments. The existing empirical literature is ambiguous on this issue. Here we account for the disparate results and find a significant negative relationship. This relationship is found to depend crucially on the time dimension of the data. We also find that oil price volatility and inflation uncertainty, as indicators of world and general shocks, are robustly correlated with growth. [source]

Parallel four-dimensional Haralick texture analysis for disk-resident image datasets

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 1 2007
Brent Woods
Abstract Texture analysis is one possible method of detecting features in biomedical images. During texture analysis, texture-related information is found by examining local variations in image brightness. Four-dimensional (4D) Haralick texture analysis is a method that extracts local variations along space and time dimensions and represents them as a collection of 14 statistical parameters. However, application of the 4D Haralick method on large time-dependent image datasets is hindered by data retrieval, computation, and memory requirements. This paper describes a parallel implementation using a distributed component-based framework of 4D Haralick texture analysis on PC clusters. The experimental performance results show that good performance can be achieved for this application via combined use of task- and data-parallelism. In addition, we show that our 4D texture analysis implementation can be used to classify imaged tissues. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Temporal Elements in the Spatial Extension of Production Networks

GROWTH AND CHANGE, Issue 4 2006
JOHAN WOXENIUS
ABSTRACT The spatial extension of production networks presents a significant challenge to managers accustomed to reducing lead times by geographically contracting supply chains. This paper extends the theory on time in transportation by defining the elements of transport time, order time, timing, punctuality, and frequency and elaborating on their characteristics. Structured along these elements, it analyses the consequences of extending production networks from within a mature economic region, mainly the EU-15, U.S., and Japan, first to adjacent and then to nearby and finally distant low-cost regions. Distance obviously affects the transport quality in all time dimensions. Except for air parcel services that globally match what road transport offers within an economic region, the longer the distance, the lower the time-related performance. Distant, low-cost regions, meaning China and India, also imply a polarisation between air and sea transport at opposite ends of the time, cost, and capacity scales. This supply gap restricts the types of products traded. The conceptual framework is illustrated in the setting of a global vehicle manufacturer spatially extending its sourcing. It demands that sequenced sub-assemblies and small, cheap, and generic components are delivered from the vicinity of each assembly plant. Batched components can be sourced from adjacent regions, but deliveries from longer distances imply storage at pick-up points to fulfil their time requirements. Hence, the suppliers must offer the manufacturing firm deliveries as if they produce relatively close to the assembly plants. [source]

Non-parametric regression with a latent time series

THE ECONOMETRICS JOURNAL, Issue 2 2009
Oliver Linton
Summary, In this paper we investigate a class of semi-parametric models for panel data sets where the cross-section and time dimensions are large. Our model contains a latent time series that is to be estimated and perhaps forecasted along with a non-parametric covariate effect. Our model is motivated by the need to be flexible with regard to the functional form of covariate effects but also the need to be practical with regard to forecasting of time series effects. We propose estimation procedures based on local linear kernel smoothing; our estimators are all explicitly given. We establish the pointwise consistency and asymptotic normality of our estimators. We also show that the effects of estimating the latent time series can be ignored in certain cases. [source]