Advanced Spectrum Functionalities for Future Radio Networks

The IST WINNER (WINNER is part of the European Union research programme within the Sixth Framework Programme (FP6) of the European Information Society Technology (IST) programme. Accepted for the Wireless World Research Forum (WWRF) 2006 Industrial Forum (Kermoal, J.-P. et al. (2006). Spectrum deployment scenarios and advanced functionalities development in WINNER.) project is a major European research activity to develop a flexible and scalable radio access system for 4G, which is addressing the challenging requirements for future systems such as those of the International Telecommunication Union (ITU) in terms of overall performance, flexibility, scalability and optimized spectrum usage. In this article, the Radio Resource Management (RRM) spectrum functionalities are defined and subsequently analyzed. The proposed RRM spectrum architecture developed will result in reducing the time required to tailor new services to network operators. Furthermore, the flexible spectrum access and usage leads to more capable and faster services with high Quality-of-Service (QoS) giving more user satisfaction than conventional networks. The inherent centralization and decentralization degree for the functionalities is outlined and discussed since flexible spectrum techniques on both fast and slow basis will lead to a better utilization of spectrum.

Faceting, composition and crystal phase evolution in III-V antimonide nanowire heterostructures revealed by combining microscopy techniques

III-V antimonide nanowires are among the most interesting semiconductors for transport physics, nanoelectronics and long-wavelength optoelectronic devices due to their optimal material properties. In order to investigate their complex crystal structure evolution, faceting and composition, we report a combined scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning tunneling microscopy (STM) study of gold-nucleated ternary InAs/InAs(1-x)Sb(x) nanowire heterostructures grown by molecular beam epitaxy. SEM showed the general morphology and faceting, TEM revealed the internal crystal structure and ternary compositions, while STM was successfully applied to characterize the oxide-free nanowire sidewalls, in terms of nanofaceting morphology, atomic structure and surface composition. The complementary use of these techniques allows for correlation of the morphological and structural properties of the nanowires with the amount of Sb incorporated during growth. The addition of even a minute amount of Sb to InAs changes the crystal structure from perfect wurtzite to perfect zinc blende, via intermediate stacking fault and pseudo-periodic twinning regimes. Moreover, the addition of Sb during the axial growth of InAs/InAs(1-x)Sb(x) heterostructure nanowires causes a significant conformal lateral overgrowth on both segments, leading to the spontaneous formation of a core-shell structure, with an Sb-rich shell.     

A new in vivo Raman probe for enhanced applicability to the body

This paper describes a new in vivo Raman probe that allows investigation of areas of the body that are otherwise difficult to access. It is coupled to a previously described commercially available in vivo Raman spectrometer that samples the skin through an optical flat. In the work presented here, the laser light emerges from a smaller pen-shaped probe. It thus works on the same principles as the original spectrometer, while its relative performance in terms of signal-to-noise ratio of the spectra and obtained spatial resolution is only slightly diminished. It allows the window to be placed against the subject in more curved and recessed areas of subject's body and also for them to be more comfortable while the measurements take place. Results from three areas of the body that have previously been very difficult to study are described, the mouth, axilla, and scalp. Results from the scalp and axilla strata cornea (SC) show significant differences from the "normal" SC of the volar forearm. For instance, the scalp is observed to have lower amounts of natural moisturizing factors (NMF) compared to the volar forearm within the same subjects. Also for both the axilla and scalp the lipids show a change in order as compared to the lipids in the volar forearm and also differences from each other. The potential significance of these observations is discussed. Further, we show how we can probe the mouth, in this case observing the presence of the astringent tea polyphenol epigallocatechin gallate within the oral mucosa.     

Rationale for the Use of Upfront Whole Brain Irradiation in Patients with Brain Metastases from Breast Cancer

Breast cancer is the second most common cause of brain metastases and deserves particular attention in relation to current prolonged survival of patients with metastatic disease. Advances in both systemic therapies and brain local treatments (surgery and stereotactic radiosurgery) have led to a reappraisal of brain metastases management. With respect to this, the literature review presented here was conducted in an attempt to collect medical evidence-based data on the use of whole-brain radiotherapy for the treatment of brain metastases from breast cancer. In addition, this study discusses here the potential differences in outcomes between patients with brain metastases from breast cancer and those with brain metastases from other primary malignancies and the potential implications within a treatment strategy.     

Pascal's triangle: An origin of Daubechies polynomials and an analytic expression for associated filter coefficients

After showing that Daubechies polynomial coefficients can be simply obtained from Pascal's triangle by some elementary additions, we propose a derivation of the spectral factorization by using the elementary symmetric functions. This derivation leads us to present an analytic expression, able to compute Daubechies wavelet filter coefficients from the roots of the associated Daubechies polynomial. Thus, these coefficients are directly obtained and without recurrence. At last, we measure the quality of the coefficient sets generated by this expression and we compare it with two well-known methods.     

Cooperative Object Segmentation and Behavior Inference in Image Sequences

In this paper, we propose a general framework for fusing bottom-up segmentation with top-down object behavior inference over an image sequence. This approach is beneficial for both tasks, since it enables them to cooperate so that knowledge relevant to each can aid in the resolution of the other, thus enhancing the final result. In particular, the behavior inference process offers dynamic probabilistic priors to guide segmentation. At the same time, segmentation supplies its results to the inference process, ensuring that they are consistent both with prior knowledge and with new image information. The prior models are learned from training data and they adapt dynamically, based on newly analyzed images. We demonstrate the effectiveness of our framework via particular implementations that we have employed in the resolution of two hand gesture recognition applications. Our experimental results illustrate the robustness of our joint approach to segmentation and behavior inference in challenging conditions involving complex backgrounds and occlusions of the target object.     

A security approach for off-chip memory in embedded microprocessor systems

This paper describes a complete off-chip memory security solution for embedded systems. Our security core is based on a one-time pad (OTP) encryption circuit and a CRC-based integrity checking module. These modules safeguard external memory used by embedded processors against a series of well-known attacks, including replay attacks, spoofing attacks and relocation attacks. Our implementation limits on-chip memory space overhead to less than 33% versus memory used by a standard microprocessor and reduces memory latency achieved by previous approaches by at least half. The performance loss for software execution with our solution is only 10% compared with a non-protected implementation. An FPGA prototype of our security core has been completed to validate our findings.     

A comparative study of existing metrics for 3D-mesh segmentation evaluation

In this paper, we present an extensive experimental comparison of existing similarity metrics addressing the quality assessment problem of mesh segmentation. We introduce a new metric, named the 3D Normalized Probabilistic Rand Index (3D-NPRI), which outperforms the others in terms of properties and discriminative power. This comparative study includes a subjective experiment with human observers and is based on a corpus of manually segmented models. This corpus is an improved version of our previous one (Benhabiles et al. in IEEE International Conference on Shape Modeling and Application (SMI), 2009). It is composed of a set of 3D-mesh models grouped in different classes associated with several manual ground-truth segmentations. Finally the 3D-NPRI is applied to evaluate six recent segmentation algorithms using our corpus and the Chen et al.’s (ACM Trans. Graph. (SIGGRAPH), 28(3), 2009) corpus.