Skin cancer is one of the most common forms of cancer worldwide and its early detection its key to achieve an effective treatment of the lesion. Commonly, skin cancer diagnosis is based on dermatologist expertise and pathological assessment of biopsies. Although there are diagnosis aid systems based on morphological processing algorithms using conventional imaging, currently, these systems have reached their limit and are not able to outperform dermatologists. In this sense, hyperspectral (HS) imaging (HSI) arises as a new non-invasive technology able to facilitate the detection and classification of pigmented skin lesions (PSLs), employing the spectral properties of the captured sample within and beyond the human eye capabilities. This paper presents a research carried out to develop a dermatological acquisition system based on HSI, employing 125 spectral bands captured between 450 and 950 nm. A database composed of 76 HS PSL images from 61 patients was obtained and labeled and classified into benign and malignant classes. A processing framework is proposed for the automatic identification and classification of the PSL based on a combination of unsupervised and supervised algorithms. Sensitivity and specificity results of 87.5% and 100%, respectively, were obtained in the discrimination of malignant and benign PSLs. This preliminary study demonstrates, as a proof-of-concept, the potential of HSI technology to assist dermatologists in the discrimination of benign and malignant PSLs during clinical routine practice using a real-time and non-invasive hand-held device.

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This paper studies the variation on the power budget, in an infrared optical link, for indoor channels with multipath propagation. The multkath propagation produces heavy distortion over the received signal and reduces the maximum baud rate for a given bit error rate.Focusing on IR wireless local area network (rR WLAN), we stu& some emitter and receiver configurations. In order to allow computer portability these link can be di&e or quasi-diffuse. These channels do not rely upon the line-ofthe-sight path. This works deals not only with the total received power, but with its time and spatial distribution. This paper considers the channel as characterized by its channel transfer function in a deterministic way. This is a good approximation if the variations in the environmental conditions are slow enough compared with the baud rate of the communication system. The source is an IR Emitter Diode @ED) with dgerent values of directiviq, pointing to a refrecting surface, white the receiver is a photodiode characterized through its Jeld of view (F.0.K) value. The results show that an optical Q-diffuse link improves the performances of a diffuse one. We use for the comparative analysis the RMS spread delay of the impulse response, the spatial distribution of received power and its standard deviation ?om the mean. We present extensive simulation results, an emitter configuration and the first measured results obtained using and APD as receiver. 924 7d.3.1

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