A fast triangle to triangle intersection test for collision detection

The triangle‐to‐triangle intersection test is a basic component of all collision detection data structures and algorithms. This paper presents a fast method for testing whether two triangles embedded in three dimensions intersect. Our technique solves the basic sets of linear equations associated with the problem and exploits the strong relations between these sets to speed up their solution. Moreover, unlike previous techniques, with very little additional cost, the exact intersection coordinates can be determined. Finally, our technique uses general principles that can be applied to similar problems such as rectangle‐to‐rectangle intersection tests, and generally to problems where several equation sets are strongly related. We show that our algorithm saves about 20% of the mathematical operations used by the best previous triangle‐to‐triangle intersection algorithm. Our experiments also show that it runs 18.9% faster than the fastest previous algorithm on average for typical scenarios of collision detection (on Pentium 4). Copyright © 2006 John Wiley & Sons, Ltd.     

The perception of pedestrians from the perspective of elderly experienced and experienced drivers

We examined hazard perception (HP) abilities among elderly experienced and experienced drivers, with regard to the presence of pedestrians in residential areas. Two evaluation methods were used: (a) observation of traffic scene videos and pressing a button when a hazardous situation was identified, and (b) driving in a driving simulator. The results of the video observation method showed that elderly drivers had a longer response time for hazard detection. In addition, four of the eight pedestrian-related events were difficult for elderly drivers to perceive when compared to experienced drivers. Elderly drivers, shown to have limited useful field of view, may also be limited in their ability to detect hazards, particularly when located away from the center of the screen. Results from the simulator drive showed that elderly drivers drove about 20% slower than experienced drivers, possibly being aware of their deficiencies in detecting hazards and slower responses. Authorities should be aware of these limitations and increase elderly drivers' awareness to pedestrians by posting traffic signs or dedicated lane marks that inform them of potential upcoming hazards.     

Personalized Hydrogels for Engineering Diverse Fully Autologous Tissue Implants

Despite incremental improvements in the field of tissue engineering, no technology is currently available for producing completely autologous implants where both the cells and the scaffolding material are generated from the patient, and thus do not provoke an immune response that may lead to implant rejection. Here, a new approach is introduced to efficiently engineer any tissue type, which its differentiation cues are known, from one small tissue biopsy. Pieces of omental tissues are extracted from patients and, while the cells are reprogrammed to become induced pluripotent stem cells, the extracellular matrix is processed into an immunologically matching, thermoresponsive hydrogel. Efficient cell differentiation within a large 3D hydrogel is reported, and, as a proof of concept, the generation of functional cardiac, cortical, spinal cord, and adipogenic tissue implants is demonstrated. This versatile bioengineering approach may assist to regenerate any tissue and organ with a minimal risk for immune rejection.     

Propaganda as a research field: a bibliometric study

Scientometrics - In its efforts to direct thought and with the help of technological developments that allow it to spread more easily and quicker than ever before, propaganda has become a dominant...     

Editing landscapes: Experimental frameworks for territorial-based robotic fabrication

With the advent of on-site robotic tools, they can be deployed for editing landscapes – defined as the modulation of grounds with a high degree of sensitivity to matter and form. The paper contributes a theoretical grounding and two experimental frameworks for territorial-based robotic fabrication. Each experimental framework supports a robotic capacity for informing and forming grounds, demonstrated in relation to extreme territories using simulation setups. The frameworks include (1) a layer-sensitive modulation for protecting topsoil and (2) a performance-based robotic forming for creating wind barriers. For each framework, the paper proposes a setup, an exploration method, and an evaluation process. Drawing on the presented frameworks, the paper outlines three potentials of territorial-based robotic fabrication: the capability to modulate grounds vertically, the possibility to perform cross-scalar forming, and the opportunity to form dynamic, performative landscapes. The paper concludes with potential ways in which robotic tools could be leveraged for advancing precise landscape editing across scales.     

Rooted in the home garden and in the nation's landscape: Women and the emerging Hebrew garden in Palestine

In the early 20th century, the Hebrew women in Palestine found the fulfillment of their economic, social, and emotional needs in gardening. Their gardens were women's means of shaping their surroundings, mainly in the family sphere but also in the community sphere (school and kindergarten gardens, kibbutz gardens). The project was an outcome of the shared interests of pioneer women, city dwellers, and Jewish women's organizations, which differed in their social status and life goals, yet shared a common fertile ground. Through the investigation of primary and secondary sources that deal with women, gardens and the history of the Zionist settlement in Palestine, this paper argues that planting gardens was the Hebrew women's modest way of creating a ‘space of their own’, where they nurtured and fostered beauty, productivity, self-esteem, mutual help and friendship, while overcoming class distinction. Meanwhile, in planting gardens, women gained a share in the Zionist nation-building project, which was primarily male dominated.     

Directed integration of minute virus of mice DNA into episomes

Recent studies with adeno-associated virus (AAV) have shown that site-specific integration is directed by DNA sequence motifs that are present in both the viral replication origin and the chromosomal preintegration DNA and that specify binding and nicking sites for the viral regulatory Rep protein. This finding raised the question as to whether other parvovirus regulatory proteins might direct site-specific recombination with DNA targets that contain origin sequences functionally equivalent to those described for AAV. To investigate this question, active and inactive forms of the minute virus of mice (MVM) 3' replication origin, derived from a replicative-form dimer-bridge intermediate, were propagated in an Epstein-Barr virus-based shuttle vector which replicates as an episome in a cell-cycle-dependent manner in mammalian cells. Upon MVM infection of these cells, the infecting genome integrated into episomes containing the active-origin sequence reported to be efficiently nicked by the MVM regulatory protein NS1. In contrast, MVM did not integrate into episomes containing either the inactive form of the origin sequence reported to be inefficiently nicked by NS1 or the active form from which the NS1 consensus nick site had been deleted. The structure of the cloned MVM episomal recombinants displayed several features previously described for AAV episomal and chromosomal recombinants. The findings indicate that the rules which govern AAV site-specific recombination also apply to MVM and suggest that site-specific chromosomal insertions may be achievable with different autonomous parvovirus replicator proteins which recognize binding and nicking sites on the target DNA.     

A state-space formulation of the causal linear prefiltering problem in sampled-data systems

In this paper, we consider the problem of linearly prefiltering and coding a random process which is to be sampled in time and transmitted over a noisy channel. We take the linear reconstruction filter at the receiving end to be fixed and known, and we then determine the form of the optimum linear prefilter subject to a power constraint on its output. If the process to be filtered is described using a state-space representation, the prefilter can be realized as a continuous Kalman filter followed by a digital filter which in general has memory. If the duration of the impulse response of the reconstruction filter is less than the interval between adjacent samples, the digital filter becomes a memoryless matrix coder.     

Nanotechnological strategies for engineering complex tissues

Tissue engineering aims at developing functional substitutes for damaged tissues and organs. Before transplantation, cells are generally seeded on biomaterial scaffolds that recapitulate the extracellular matrix and provide cells with information that is important for tissue development. Here we review the nanocomposite nature of the extracellular matrix, describe the design considerations for different tissues and discuss the impact of nanostructures on the properties of scaffolds and their uses in monitoring the behaviour of engineered tissues. We also examine the different nanodevices used to trigger certain processes for tissue development, and offer our view on the principal challenges and prospects of applying nanotechnology in tissue engineering.     

Can art breach boundaries? Segregation and hierarchy at a fringe theatre festival in the Israeli mixed city of Acre

Abstract

This study explores the relationship between art and urban boundaries using the case study of a fringe theatre festival in the Israeli mixed-city of Acre. While mixed cities today are understood as agglomerations of enclaves, maintained and reinforced by boundaries, urban designers and artists have used art as a culture-led regeneration strategy through which these boundaries may be breached. This study undermines the shared assumption of both fields: that art has the power to breach boundaries, by juxtaposing a city’s artistic activity with its segregation patterns and boundaries. Using super-positioning, the findings of two research methods have been integrated: urban research and ethnographic field work. The article shows that although the artistic activity in question is rooted in an avant-garde radical desire to subvert socioeconomic structures, it actually produces new versions and interpretations of the same segregations and boundaries in both space and society.