Search results for "Computer graphics"

Model studies on a diastereoselective synthesis of the C(33)–C(37) fragment of Amphotericin B

2003

Abstract A new, short and highly diastereoselective synthetic route aiming at the C(33)–C(37) fragment of Amphotericin B has been developed. Studies with a model aldehyde (benzaldehyde) have given very promising results: the desired stereochemistry of all four stereocenters of the target molecule has been achieved with high diastereoselection. The stereochemistry of three key intermediates and the target segment has been confirmed by X-ray crystallography.

Theoretical studies on cycloaddition reactions

2014

Cycloaddition reactions represent one of the most powerful processes in organic chemistry. The most common types of cycloaddition reactions are the Diels-Alder (DA) and the 1,3-dipolar cycloaddition reactions (1,3-DCs) which lead to five and six membered rings, respectively. In our ongoing efforts to contribute to the understanding of DA and 1,3-DCs; we studied the following using the B3LYP/6-31G(d) level of theory: 1. The 1,3-DCs of the pyridinium-3-olates and pyrazinium-3-olates with methyl acrylate and methyl methacrylate [1,2]. 2. The competitive hetero-DA and 1,3-DCs of methyl glyoxylate oxime and its tautomeric nitrone with cyclopentadiene in the absence and in the presence of BF3 as …

Impact of Wavelet Kernels on Predictive Capability of Radiomic Features: A Case Study on COVID-19 Chest X-ray Images

2023

Radiomic analysis allows for the detection of imaging biomarkers supporting decision-making processes in clinical environments, from diagnosis to prognosis. Frequently, the original set of radiomic features is augmented by considering high-level features, such as wavelet transforms. However, several wavelets families (so called kernels) are able to generate different multi-resolution representations of the original image, and which of them produces more salient images is not yet clear. In this study, an in-depth analysis is performed by comparing different wavelet kernels and by evaluating their impact on predictive capabilities of radiomic models. A dataset composed of 1589 chest X-ray ima…

Creative interpretation in web design experience

2017

Insight into how people mentally represent, and thus, make sense of visual designs is the key to understanding how people interact with technological devices. This paper presents a study in which participants were asked to write their interpretations of two webpage design examples, based on what they thought they would say and what would remain as a thought. The data comprised 80 3E templates (N = 40), a template allowing participants to express experiences through writing and drawing. Inductive data analysis through a phenomenological lens revealed that supposed mental and verbal representations concentrated on the following design properties: colors, themes, interface layout and quality, …

Tradition and virtuality: The Caltagirone staircase

2006

OntoSTEP: Enriching product model data using ontologies

2012

The representation and management of product lifecycle information is critical to any manufacturing organization. Different modeling languages are used at different lifecycle stages, for example STEP's EXPRESS may be used at a detailed design stage, while UML may be used for initial design stages. It is necessary to consolidate product information created using these different languages to build a coherent knowledge base. In this paper, we present an approach to enable the translation of STEP schema and its instances to Ontology Web Language (OWL). This gives a model-which we call OntoSTEP-that can easily be integrated with any OWL ontologies to create a semantically rich model. As an examp…

A Dataset of Annotated Omnidirectional Videos for Distancing Applications

2021

Omnidirectional (or 360°) cameras are acquisition devices that, in the next few years, could have a big impact on video surveillance applications, research, and industry, as they can record a spherical view of a whole environment from every perspective. This paper presents two new contributions to the research community: the CVIP360 dataset, an annotated dataset of 360° videos for distancing applications, and a new method to estimate the distances of objects in a scene from a single 360° image. The CVIP360 dataset includes 16 videos acquired outdoors and indoors, annotated by adding information about the pedestrians in the scene (bounding boxes) and the distances to the camera of some point…

Economic specialization and diversification at the country and regional level: introducing a conceptual framework to study innovation policy logics

2018

While there has been a shared understanding that innovation policy is about rendering institutional change, there has been an emerging interest in identifying the institutional logics underlying in...

A scalable multiagent system architecture for interactive applications

2013

Interactive applications like crowd simulations need to properly render the virtual world while simulating the interaction of thousands of agents at the same time. The computational workload generated by these two tasks highly increases with the number of the simulated agents, requiring a scalable design of the multiagent system. In this paper, we present, in an unified manner, a distributed multiagent system architecture that can manage large crowds of autonomous agents at interactive rates while rendering multiple views of the virtual world being simulated. This architecture consists of a distributed multiagent system and a complementary distributed visualization subsystem. We also presen…

A distributed visualization system for crowd simulations1

2011

The visualization system of large-scale crowd simulations should scale up with both the number of visuals views of the virtual world and the number of agents displayed in each visual. Otherwise, we could have large scale crowd simulations where only a small percentage of the population is displayed. Several approaches have been proposed in order to efficiently render crowds of animated characters. However, these approaches either render crowds animated with simple behaviors or they can only support a few hundreds of user-driven entities. In this paper, we propose a distributed visualization system for large crowds of autonomous agents that allows the visualization of crowds animated with co…