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Objective: There is a need to elucidate the underlying neural mechanisms subserving working memory and divided attention functioning. Recent neuroimaging studies provide evidence for anatomical co-localization of both functions. In the present study we used a functional intervention, whereby we applied a novel type of focalised, non-invasive brain stimulation, High-Definition transcranial Direct Current Stimulation (HD-tDCS), to the regions subserving these processes, the left intraparietal sulcus (IPS) and left dorsolateral prefrontal cortex (LDLPFC). Our aim was therefore to modulate activity in these regions using HD-tDCS and thereby assess their relevance for working memory, divided attention and their shared sub-processes.Method: 78 participants were evenly randomized to one of three conditions in a single blind, parallel group study design. Anodal or sham HD-tDCS was applied to either the left IPS or LDLPFC while participants completed a verbal working memory task, a divided attention task, and two tasks measuring subcomponents of working memory (updating and maintenance).Results: Focalised stimulation of the IPS and LDLPFC did not significantly modulate performance compared to sham stimulation. However, moderate effect sizes were obtained for at least one HD-tDCS condition relative to sham for all tasks, warranting further research into the functional importance of the IPS in subserving these abilities.Conclusions: The current results may be useful for informing future tDCS studies for modulating working memory and divided attention functioning.

Our paper introduces a combined model approach using systemdynamics simulating regional drivers and cellular automaton representing localland-use dynamics. The model benefits from conclusive causal interrelations ofdetailed population dynamics, real household decision parameters, residentialdemand on prevailing residential land use types and residential supply as a resultof dynamic housing parameters. Consequently, we can simulate growth andshrinkage processes to occur concurrently within an urban region. In this process,human decisions are covered in two ways, firstly, by bottom-up individualresidential choice-making over different residential types and secondly by top-downdecision making by planning authorities. The model is applied to the metropolitanregion of Berlin. It provides more plausible results compared to cellular automataapproaches using conventional trend based regional input models. Humandecisions on land-use are displayed in six scenarios representing possible futurepaths of Berlin´s urban development from 2008 to 2030. The findings indicate thatthe effect on residential patterns due to different planning approaches is equal tothe effect introduced by the likely maximum deviation of economic anddemographic trends as proved by kappa values. A quality assessment confirms thebenefit of the combined approach and affirms that the model functionality is sound.

Our paper introduces a combined model approach using systemdynamics simulating regional drivers and cellular automaton representing localland-use dynamics. The model benefits from conclusive causal interrelations ofdetailed population dynamics, real household decision parameters, residentialdemand on prevailing residential land use types and residential supply as a resultof dynamic housing parameters. Consequently, we can simulate growth andshrinkage processes to occur concurrently within an urban region. In this process,human decisions are covered in two ways, firstly, by bottom-up individualresidential choice-making over different residential types and secondly by top-downdecision making by planning authorities. The model is applied to the metropolitanregion of Berlin. It provides more plausible results compared to cellular automataapproaches using conventional trend based regional input models. Humandecisions on land-use are displayed in six scenarios representing possible futurepaths of Berlin´s urban development from 2008 to 2030. The findings indicate thatthe effect on residential patterns due to different planning approaches is equal tothe effect introduced by the likely maximum deviation of economic anddemographic trends as proved by kappa values. A quality assessment confirms thebenefit of the combined approach and affirms that the model functionality is sound.

After the fall of the Berlin wall in 1989, demographic decline and urban shrinkage brought massive changes in the housing stock in East German cities. Urban planners and policy makers face complex problems caused by the resulting vacancies and demolitions and the handling of urban brownfields in the inner city. At the same time, cities are under ongoing pressure of suburbanisation. Because existing models focus mainly on demographic and urban growth and their impact on housing stocks, we present a simulation model that is able to compute both growth and shrinkage processes. We uncover nonlinear dynamics and feedbacks between demography, housing preference, and supply of housing space. The simulation results show that, despite population decline, the increasing number of single households leads to a growing total housing demand in the central parts of the study area. Beyond this area, residential vacancies in multistorey housing segments will remain regardless of population growth. At the same time, the simulations show that, despite population shrinkage and an overall oversupply of flats, there is a negative net demand for flats in affordable prefabricated housing estates as the percentage of low-income households increases. These findings will help planners modify or adapt their visions of the residential function in shrinking cities and to adjust current programmes of renewal and restructuring.

This paper introduces an enhancement of a cellular automata (CA) model by integrating system dynamics (SD) to incorporate household dynamics and housing decisions as driving forces of residential development. CA macro-models used to simulate the quantitative land-use change (LUC) for urban areas are, thus far, lacking profound dynamics driven by demographic change. The model presented in this paper focuses on household dynamics according to the concept of the second demographic transition (SDT), applying aging and population shrinkage to simulate respective effects on residential choice and the resulting LUC. Such a perspective becomes especially important for urban areas exhibiting growth and shrinkage simultaneously, as currently seen in cities in Europe and in the U.S. To analyze this simultaneity in detail, we implement the residential land use CA model Metronamica and apply it to Berlin’s metropolitan region, which was selected as a typical example that displays contrasting growth and shrinkage processes. The pre-implemented macro-model has been replaced with our new SD model H2DCA (Household Decision Dynamics for Cellular Automata). For the simulation, we used empirical census data, economic data, data on residential satisfaction and numerous types of geo-information representing land-use zoning, accessibility and suitability for the time span 1990–2008. A comparison of a null model (NM) and H2DCA provides a very satisfying reproduction of land-use patterns reflected by kappa coefficient values. The causal relation of LUC drivers is considerably improved by sophisticated housing choice-feedback mechanisms. Although specific residential land-use classes exhibit shrinkage, others expand. Due to the detailed residential land-use classification, current re-urbanization processes could also be simulated.

Within the MPEG-21 Multimedia Framework, Digital Items are introduced as a structured digital representation for multimedia. To facilitate the representation of Digital Items which include secure or controlled content, the authors have implemented an IPMP Digital Item Declaration Language (IPMP DIDL). This provides for a protected representation of Digital Item structure, allowing the use of existing DRM systems and rights expression languages. This paper examines the design and implementation of the IPMP DIDL and its incorporation into MPEG-21 Part 4: IPMP Components.

Within the MPEG-21 Multimedia Framework, Digital Items are introduced as a structured digital representation for multimedia. To facilitate the representation of Digital Items which include secure or controlled content, the authors have implemented an IPMP Digital Item Declaration Language (IPMP DIDL). This provides for a protected representation of Digital Item structure, allowing the use of existing DRM systems and rights expression languages. This paper examines the design and implementation of the IPMP DIDL and its incorporation into MPEG-21 Part 4: IPMP Components.

Within the MPEG-21 Multimedia Framework, Digital Items are introduced as a structured digital representation for multimedia. To facilitate the representation of Digital Items which include secure or controlled content, the authors have implemented an IPMP Digital Item Declaration Language (IPMP DIDL). This provides for a protected representation of Digital Item structure, allowing the use of existing DRM systems and rights expression languages. This paper examines the design and implementation of the IPMP DIDL and its incorporation into MPEG-21 Part 4: IPMP Components.

Within the MPEG-21 Multimedia Framework, Digital Items are introduced as a structured digital representation for multimedia. To facilitate the representation of Digital Items which include secure or controlled content, the authors have implemented an IPMP Digital Item Declaration Language (IPMP DIDL). This provides for a protected representation of Digital Item structure, allowing the use of existing DRM systems and rights expression languages. This paper examines the design and implementation of the IPMP DIDL and its incorporation into MPEG-21 Part 4: IPMP Components.