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As every year, this is the time to announce the winner of the H. Mimno Award, recognizing the authors of the best paper published in the Magazine in 2015. This year the awarded paper, published in the August 2015 issue, is “ESTCube-1 In-Orbit Experience and Lessons Learned”, by A. Slavinskis, M. Pajusalu, H. Kuuste, E. Ilbis, T. Eenmae, I. Sunter, K. Laizans, H. Ehrpais, P. Liias, E. Kulu, J. Viru, J. Kalde, U. Kvell, J. Kutt, K. Zalite, K. Kahn, S. Latt, J. Envall, P. Toivanen, J. Polkko, P. Janhunen, R. Rosta, T. Kalvas, R. Vendt, V. Allik and M. Noorma.

In this paper we deal with the estimation of the covariance matrix for Complex Elliptically Symmetric (CES) data. We follow three different approaches with different level of knowledge on the specific CES model and we compare the asymptotic performances under the three approaches in terms of Cramer-Rao Bounds and Huber limit.

Compressed Sensing is a new signal processing methodology that allows to reconstruct sparse signals using a relatively small number of samples in the form of random projections. These samples are collected at a much lower rate than Nyquist rate. This paper focuses on the application of Compressed Sensing in Cognitive Radar systems that use wide operating frequency bandwidths for spectrum sensing and sharing. Compressed sensing can provide a significant reduction in acquisition time reducing the cost for high resolution analog-to-digital converters with large dynamic range, and high speed signal processors.

This paper deals with the problem of a cognitive radar system that shares the same frequency band with a communication system, supposed to be the primary user of channel. A cognitive algorithm is proposed to estimate the channel parameters that describe the behaviour of the primary user and how to exploit these estimates to minimize the interference between the radar and the communication system. The performance of the proposed algorithm are assessed in terms of probability of collision, that is the probability that the radar transmits when the primary user already occupies the channel, and probability to lose a spectrum opportunity, that is the probability that the radar does not transmit when the channel is free.

Publication in the conference proceedings of EUSIPCO, Lisbon, Portugal, 2014

This paper deals with the maximum likelihood (ML) estimation of scatter matrix of complex elliptically symmetric (CES) distributed data when the hypothesized and the true model belong to the CES family but are different, then under mismatched model condition. Firstly, we derive the Huber limit, or sandwich matrix expression, for a generic CES model. Then, we compare the performance of mismatched and matched ML estimators to the Huber limit and to the Cramer-Rao lower bound (CRLB) in some relevant study cases.

Radars operating in an open environment will receive returns from many sources. In addition to reflections from objects of interest, usually known as targets, the radar signal will include backscatter from the environment and other unwanted objects, known as radar clutter. A radar system is required to process the returns from targets in the presence of this unwanted clutter. This tutorial describes the characteristics of different types of clutter and the various ways in which clutter is modeled. It then introduces the uses of clutter models in radar design and analysis, including their use for performance prediction, the simulation of synthetic clutter signals and the specification and measurement of radar performance in the radar procurement process.

This study examines ground and sea clutter from three different FM-based passive bistatic radars (PBRs). Measurement data has been obtained for low-grazing angles. The PBRs used to collect the displayed data, with all their relevant parameters, are defined and clutter analysis procedures are described. This work, based on measured data, yields valuable insight into the nature of VHF bistatic clutter.

The effect on radar detection of the shape of the Doppler spectrum of windblown vegetated ground clutter is analyzed. An extensive experimental campaign carried out by MIT Lincoln Laboratory showed the shape of the windblown clutter Doppler spectrum to be exponential, in contrast to two other widely-used spectral models (i.e., Gaussian and power-law). The detection performance of two classes of surveillance radar, ground-based and Airborne Early Warning, is evaluated and compared against windblown ground clutter using the three above-mentioned Doppler spectral shapes. The analysis is first done with closed-form equations, and subsequently validated using a set of measured clutter data. It is demonstrated that the exponentially shaped Doppler spectrum should be used as the reference to model windblown ground clutter for the prediction of radar detection performance.

We investigate the robustness of the linear matched filter (MF) operating in a Gaussian environment in the presence of a mismatch between the design clutter-power spectral density (PSD) shape and the actual one. The Gaussian, the power-law (PL), and the double-exponential spectral models have been considered with the goal of investigating which one fits best for windblown foliage. We analyze the MF performance in terms of improvement factor, probability of false alarm, and probability of detection by making use of the theoretical models and measured X-band ground clutter data. The numerical results validate the double-exponential spectral model for windblown foliage by showing that the differences in performance prediction between using measured clutter data and modeled clutter data of various spectral shapes (viz., Gaussian, FL, and double-exponential) are minimized when the spectral model employed is of double-exponential shape.

Subspace approaches have become popular in the last two decades for retrieving constant amplitude harmonics observed in white additive noise because they may exhibit superior resolution over the FFT-based methods, especially with short data records and closely spaced harmonics. We demonstrate that MUSIC and ESPRIT methods can also be applied when the harmonics are corrupted by white or wideband multiplicative noise. The application context is the retrieval of texture information from high resolution and low grazing angle radar clutter data affected by wideband colored speckle that is modeled as complex multiplicative noise. Texture information is fundamental for clutter cancellation and constant false alarm rate (CFAR) radar detection. A thorough numerical analysis compares the two subspace methods and validates the theoretical findings.

Adaptive detection of fluctuating radar targets in unknown correlated Gaussian clutter has received considerable attention in the past. On the other hand, the problem of adaptive detection in non-Gaussian environments is still under investigation. Adaptive coherent radar detection of Swerling I targets against compound-Gaussian clutter is addressed. Our contribution is (1) to present a detection algorithm, called the adaptive linear-quadratic (ALQ) detector, with constant false-alarm rate (CFAR) behavior with respect to the clutter amplitude probability density function (apdf) and that is quite insensitive to the clutter correlation structure, and (2) to investigate and compare the performance of the ALQ detector and Kelly's generalized likelihood ratio test (GLRT) against K-distributed clutter.

This paper addresses the problem of signal detection in correlated non-Gaussian clutter modeled as a spherically invariant random process. The optimum strategy to detect a constant signal, with either known or unknown complex amplitude, embedded in correlated Gaussian clutter is given by comparing the whitening-matched filter output with a fixed threshold. When the clutter is non-Gaussian, the performance of the matched filter sensibly degrades. The optimum strategy is the classical whitening-matched filter output compared with a data-dependent threshold. This interpretation provides a deeper insight into the structure of the optimum detector and allows us to single out a family of suboptimum detectors based on a polynomial approximation of the data-dependent threshold. They are easy to implement and have performance that is really close to the optimal. The adaptive implementation of the polynomial detectors is also investigated, and their performance is analyzed by means of Monte Carlo simulation for various clutter scenarios.

The problem of coherent radar target detection in a background of non-Gaussian clutter modeled by a compound Gaussian distribution is studied here. We show how the likelihood ratio may be recast into an estimator-correlator form that shows that an essential feature of the optimal detector is to compute an optimum estimate of the reciprocal of the unknown random local power level. We then proceed to show that the optimal detector may be recast into yet another form, namely a matched filter compared with a data-dependent threshold. With these reformulations of the optimal detector, the problem of obtaining suboptimal detectors may be systematically studied by either approximating the likelihood ratio directly, utilizing a suboptimal estimate in the estimator-correlator structure or utilizing a suboptimal function to model the data-dependent threshold in the matched filter interpretation. Each of these approaches is studied to obtain suboptimal detectors. The results indicate that for processing small numbers of pulses, a suboptimal detector that utilizes information about the nature of the non-Gaussian clutter can be implemented to obtain quasi-optimal performance. As the number of pulses to be processed increases, a suboptimal detector that does not require information about the specific nature of the non-Gaussian clutter may be implemented to obtain quasi-optimal performance.

The performance of ground-based surveillance radars strongly depends on the distribution and spectral characteristics of ground clutter. To design signal processing algorithms that exploit the knowledge of clutter characteristics, a preliminary statistical analysis of ground-clutter data is necessary. We report the results of a statistical analysis of X-band ground-clutter data from the MIT Lincoln Laboratory Phase One program. Data non-Gaussianity of the in-phase and quadrature components was revealed, first by means of histogram and moments analysis, and then by means of a Gaussianity test based on cumulants of order higher than the second; to this purpose parametric autoregressive (AR) modeling of the clutter process was developed. The test is computationally attractive and has constant false alarm rate (CFAR). Incoherent analysis has also been carried out by checking the fitting to Rayleigh, Weibull, log-normal, and K-distribution models. Finally, a new modified Kolmogorov-Smirnoff (KS) goodness-of-fit test is proposed; this modified test guarantees good fitting in the distribution tails, which is of fundamental importance for a correct design of CFAR processors.

Occupational health has been the scope of numerous studies, primarily due to the concern that the worker should enjoy good working conditions and a satisfactory quality of life. This study seeks to analyze the impact of oral health on the quality of life of workers at a public university using the simplified version of the Oral Health Impact Profile (OHIP-14) and associated factors. A cross-sectional study was conducted with 326 workers who responded the questions of OHIP-14 about self-rated health, oral morbidity, and socioeconomic and demographic questions. Multiple linear regression analysis was performed to verify the association between the independent variables and OHIP-14. About 40% of the impact of oral health on quality of life can be explained by the variables: education level (p = 0,03), age (p = 0,03), reason for visiting a dentist (p = 0,01), oral health perception (p < 0,01) and satisfaction with teeth and mouth (p < 0,01). The use of OHIP-14 can be useful for planning programs and actions focused on health education for occupational health, prioritizing workers with greater psychosocial impacts caused by oral problems.

Publication in the conference proceedings of EUSIPCO, Marrakech, Morocco, 2013

We consider covariance estimation in the multivariate generalized Gaussian distribution (MGGD) and elliptically symmetric (ES) distribution. The maximum likelihood optimization associated with this problem is non-convex, yet it has been proved that its global solution can be often computed via simple fixed point iterations. Our first contribution is a new analysis of this likelihood based on geodesic convexity that requires weaker assumptions. Our second contribution is a generalized framework for structured covariance estimation under sparsity constraints. We show that the optimizations can be formulated as convex minimization as long the MGGD shape parameter is larger than half and the sparsity pattern is chordal. These include, for example, maximum likelihood estimation of banded inverse covariances in multivariate Laplace distributions, which are associated with time varying autoregressive processes.

This paper presents a new idea for cognitive radar operating in spectrally dense environments. In particular, the case is addressed when the instantaneous frequency of the radar, assumed to be a wideband or ultra wideband radar, spans several channels, which are used at the same time by other users for communication services. This work proposes a decentralized frequency sharing protocol, which optimizes the performance of the radar and, at the same time, limits the interference received by the other users.

For many years, conventional radars transmitted, received, and processed the same waveform on every pulse or burst within a coherent processing interval (CPI), independently of the environment. Now, modern radar systems have considerable flexibility in their modes of operation, both on receive and transmit. In particular, it is possible to modify the waveform on a pulse to pulse basis, and electronically steered phased arrays can quickly point the radar beam in any feasible direction. In the course of this research project, we introduced the Ambiguity Function, an analytical tool for waveform design and analysis that is useful for examining resolution, sidelobe behavior, and ambiguity in range and Doppler of a given signal waveform. Some techniques to design multiple access frequency hop codes with good auto and cross-ambiguity functions are characterized, focusing on the frequency hop patterns. We have shown that the performance of each channel of the multistatic system heavily depends on the transmitted waveform and on the geometry of the scenario, that is, the position of receivers and transmitters with respect to the position of the target. In particular, both geometry factors and transmitted waveforms play an important role in the shape of the Ambiguity Function and hence in the value of the Cramer-Rao Lower Bound (CRLB). We have calculated the bistatic CRLBs of target range and velocity of each transmit-receive pair as a function of the target kinematic parameters and to provide a local measure of the estimation accuracy of these parameters. Finally, in this work we have analyzed the problem of the optimum sensor selection along the trajectory of a tracked target in a multistatic radar systems. To this end we have evaluated the Posterior Cramer-Rao Lower Bound (PCRLB) of the sequential target state estimation and we will define an algorithm that exploits this mathematical tool to select the best channels for the tracking of the target.

A partir de revisão bibliográfica, as autoras discorrem sobre a questão das políticas públicas de saúde no Brasil, procedendo a uma re-leitura do processo. Apontam para a importância da discussão sobre a questão nos cursos de graduação em Enfermagem.Authors presents an evolution of the public health's politics in Brasil through a critical review of the historical process. Besides this they call to the importance of this issue in the undergraduate curricular in nursing.

Trata-se de um relato de experiência que aborda a vivência de alunas do curso de pós-graduação Mestrado em Enfermagem na disciplina Tecnologia em Saúde e em Enfermagem. Este estudo teve como objetivo descrever o processo de concepção de uma tecnologia para o cuidado em enfermagem e saúde. As alunas, estimuladas a associar o uso da tecnologia para solucionar um problema de enfermagem, apresentaram a ideia de aprimorar o modelo de carro-maca existente no mercado, uma vez que o produto atual apresenta vários riscos para os profissionais que o manuseiam, como também para os pacientes transportados. A proposta possibilita reduzir o absenteísmo laboral por motivo de lesões ergonômicas e proporcionar conforto e segurança ao usuário. A abordagem do empreendedorismo como disciplina dentro da academia proporcionou ampliar horizontes durante a formação no mestrado das alunas que, enquanto futuras docentes, estão conscientes da capacidade do empreendedorismo e do uso da tecnologia para propiciar mudanças no cenário na enfermagem.

O Trabalho relata um programa de revisão da prática assistencial prestada na Unidade de Saúde da região-alvo do Projeto de Integração Docente-Assistencial - Escola de Enfermagem da Universidade de São Paulo e Município de São Paulo. Envolveu-se no programa a grande maioria dos trabalhadores da Unidade que, em 8 sessões conjuntas, repensou a sua prática de trabalho, elaborando um rol de propostas de transformação da assistência. O trabalho teve como grande mérito permitir o envolvimento efetivo dos integrantes e o desencadeamento de um processo de discussão e reflexão, conjunto e participativo.En trabajo describe un programa de revisión de la práctica asistencial en una Unidad de Salud que pertenece a la región abarcada por el Proyecto de Integración Docente-Asistencial firmado entre la Escuela de Enfermería de la Universidad de São Paulo y la Municipalidad de São Paulo. Casi la totalidad de los trabajadores de la Unidad se involucraran en el programa y en las 8 reuniones conjuntas, repensaran su práctica asistencial, generando una serie de propuestas de transformación de la asistencia. El mayor mérito del trabajo fue haber permitido crear un proceso de discusión y de reflexión, colectivo y participativo.The paper shows a program concerting the review of the assistance practice in a Health Unit at the target region of the School-Service Integration Project between the College of Nursing at Ribeirão Preto/University of São Paulo and São Paulo City. The majority of the health workers took part in the program which was developed in 8 meetings where they analyzed their own working practice and elaborated several proposals aiming at champing it. The greatest merit of this program was to allow the establishment of a collective and participative process of discussion and reflection.

to evaluate the degree of exposure to PCB in a population resident in the lower Susa Valley and its effects on general and endocrine homeostasis. DESIGN, SETTING, PARTICIPANTS AND MAIN OUTCOME MEASURES: in the lower Susa Valley (Piedmont, Italy), there is a steel secondary casting plant (i.e. by fusion of scrap iron), active since the '50s. The emissions of PCB and dioxin coming from the furnace were found in samples of herb, pulse and ground in a preliminary environmental characterisation study. During 2005-2006 we run an epidemiologic study of biomonitoring (measuring as outcome common haematochemical parameters, hormonal parameters, haematic PCB) on a sample of subjects resident in the municipalities with higher levels of PCB and dioxin contamination (exposed subjects), that was compared with another sample (unexposed) of subjects residing in other areas of the Susa Valley.the final sample consisted of 244 subjects (119 unexposed and 125 exposed), balanced by gender, age, education and representative of the Susa Valley population. The greater part of hormonal and toxic parameters showed worse values among exposed than among unexposed, including PCB median value (2.30 μg/l among exposed vs. 1.90 μg/l among unexposed). The difference however was not statistically significant and the values were lower than the population reference values (7.2 μg/l). Haematic PCB values were significantly and positively correlated with age and alcohol consumption and not significantly with male gender. The distribution of the principal haematochemical parameters (hemochrome, total, LDL and HDL cholesterol, triglycerides, glucose, creatinine, bilirubin, transaminases, gamma-glutamiltranspeptidase, proteine electrophoresis) showed also, on the whole, worse values among exposed compared to unexposed, even if the difference was not statistically significant for single values.the exposed population showed higher values of PCB haematic values and alterations of the hormonal and common heamatochemical parameters compared to unexposed population, even if within reference limits.

This scope of this article is to discuss the inclusion of oral health in the Brazilian Family Health Strategy in municipalities of a micro-region of southeastern Brazil, from the standpoint of human resources. Questionnaires were distributed to members of the oral health service: dentists, assistants and managers. The instrument included three dimensions: how and why they adopted the new model; how the service is being reorganized; and what advances were perceived by professionals. The most common reason mentioned by managers for the inclusion of Oral Health was the possibility of changing the technical care model. When asked about their motivation, dentists and assistants also considered the possibility of change in practices to be a priority. It was also seen that there are critical bottlenecks in the hiring and training of human resources to work in the oral health team and in integration among health professionals. Indeed, access is enhanced either by the organization or by the expansion of the teams. The municipalities of the micro-region still encounter difficulties for the functioning of the oral health service, after Family Health, to show actual progress in care practices. However, advances exist and these need to be bolstered to consolidate the health system and improve the quality of life of the population.

An important prerequisite for successful multisensor integration is that the data from the reporting sensors are transformed to a common reference frame free of systematic or registration bias errors. If not properly corrected, registration errors can seriously degrade the global surveillance system performance. The absolute sensor registration (or grid-locking) process aligns remote data coming from sensors to an absolute reference frame. In this paper we consider a multi-target scenario and we address the problem of jointly estimating registration errors involved in the absolute grid-locking problem with two radars. A linear Least Squares (LS) estimator is derived and its statistical performance compared to the hybrid Cramer-Rao lower bound (HCRLB).

An important prerequisite for successful multisensor integration is that the data from the reporting sensors are transformed to a common reference frame free of systematic or registration bias errors. If not properly corrected, the registration errors can seriously degrade the global surveillance system performance. The relative sensor registration (or grid-locking) process aligns remote data to local data under the assumption that the local data are bias free and that all biases reside with the remote sensor. In this paper we consider a multi-target scenario and we address here the problem of jointly estimating all registration errors involved in the grid-locking problem. An Expectation-Maximization (EM) estimator of all bias errors is derived and its statistical performance compared to the hybrid Cramer-Rao lower bound (HCRLB).

The ability to recognize quickly and reliably non cooperative targets is a primary issue in modern radar systems. The use of a multistatic radar has already been demonstrated to improve sensibly the recognition capacity of a radar system, through the exploitation of its inherent spatial diversity, given by the presence of multiple observation channels. In this paper, we evaluate the performance of a multistatic radar, which uses a correlation based classification algorithm for each channel of the multistatic system and a suitable fusion rule that combines the decisions coming from different channels. This fusion rule, referred as SELX (SELection of tX and rX), takes into account that each channel decision is influenced by a number of parameters, including the relative positions between target, transmitter and receiver. As a consequence, a suitable selection is made to favour the channels which show better performance with respect to the other ones. The performance evaluation of the SELX rule is carried out and compared with a straight method that takes into account only the SNR. In both the cases the performance are carried out by considering complex targets, each of them modelled as a set of independent scatterers, according to type, form and structure of the target. Four different types of targets are modelled, which emulate real targets. The evaluation demonstrates the ability to classify the targets by means of our methods and algorithms, with a very high probability of correct classification.

O aprimoramento das formas de gestão dos serviços de saúde tem levado à busca pela qualidade. Nessa perspectiva surge o movimento de Acreditação Hospitalar que baseia-se na tríade estrutura-processos-resultado que inicia-se pelo gerenciamento dos riscos. Este estudo objetivou descrever e discutir as etapas de planejamento, implantação e avaliação do processo de mapeamento e gerenciamento de riscos em um dos setores assistenciais do Hospital Universitário da Universidade Federal de Juiz de Fora (UFJF) e foi desenvolvido através do método de pesquisa-ação onde construiu-se coletivamente com os trabalhadores do setor um processo de mapeamento e priorização dos riscos inerentes às atividades que envolviam o paciente, o trabalhador, a instituição e o meio ambiente e gerenciamento dos mesmos. Além do resultado direto na tentativa de redução destes riscos, foi possível inserir os trabalhadores nesta construção coletiva, instrumentalizando-os para a tomada de decisão e empoderando-os neste processo; contribuir para as reflexões acerca das estratégias de gerenciamento dos riscos das demais unidades do campo em que se insere e fornecer subsídios para reflexões em outras unidades de saúde na busca incansável por melhores resultados intervindo no processo saúde-doença do indivíduo, família e comunidade, traduzindo-se por satisfação e segurança do cliente, segurança para os profissionais, responsabilidade sócio-ambiental e racionalização do uso dos recursos materiais com consequente reflexo na imagem institucional.

Nesta pesquisa de natureza qualitativa utilizou-se a entrevista aberta com 19 mulheres varredoras de rua, em janeiro de 2010, com o objetivo de identificar seu conhecimento sobre o corpo e como se cuidam em relação às alterações ginecológicas. Na organização das informações emergiram as unidades de significação: conhecimento das mulheres sobre o corpo; conhecimento da mulher sobre corrimento vaginal; como as mulheres cuidam do corrimento vaginal; e o corrimento interferindo no processo de trabalho. A análise compreensiva desvelou que desconhecem ou têm pouco conhecimento sobre a genitália e, como não se cuidam, isto interfere em suas atividades laborativas. O enfermeiro possui amplo campo de ação, como educador, na prevenção e na conduta terapêutica das alterações ginecológicas, com vistas a propiciar melhor qualidade de vida. Neste sentido, a interação profissional/cliente, durante a consulta ginecológica, é excelente oportunidade para criar laços de confiança e caminhar na construção do conhecimento sobre saúde. This qualitative approach study carried out an open interview with female road sweeper in January 2010 to identify their knowledge of their own bodies and how they take care of themselves considering gynecological alterations. The following signification units were identified in the organization of information: women's knowledge of their bodies; women's knowledge of vaginal discharge; how women treat vaginal discharge; vaginal discharge intervening in the work process. Comprehensive analysis revealed that these women know nothing or a little of genitals and lack of care interfere with their work activities. Nurses have important role as educators in the prevention and in the therapeutic conduct of the gynecological alterations, aiming to provide better life quality. In this sense, the professional/client interaction during the gynecological consultation represents an excellent opportunity to establish bonds of confidence and to move towards the construction of knowledge in health. Estudio cualitativo realizado en enero 2010. Fue utilizado la entrevista abierta en 19 mujeres barrenderas de calle. Lo objetivo es identificar el conocimiento de ellas sobre su cuerpo y como se cuidan en relación a las alteraciones ginecológicas. En la organización de las informaciones emergieron las unidades de significación: conocimiento de las mujeres sobre el cuerpo; conocimiento sobre corrimiento vaginal; como las mujeres cuidan del corrimiento; el corrimiento interfiriendo en el trabajo. el análisis comprensiva mostró que las mujeres desconocen o tienen poco conocimiento sobre su genitalia y como no se cuidan, esto interfiere en el su trabajo. El enfermero tiene un amplio campo de acción como educador en la prevención e en la conducta terapéutica de las alteraciones ginecológicas, para proporcionar mejor calidad de vida. La interacción profesional/cliente durante la consulta es una excelente oportunidad para crear lazos de confianza y caminar en la construcción del conocimiento sobre salud.

This work deals with the analysis of a multisensor radar system in the context of maritime border control scenario. The system is composed by a receiver that exploits the signal emitted by two non co-operative transmitters of opportunity: a UMTS base station and a FM radio station. An algorithm for selecting the transmitter for the tracking of a radar target is proposed. This algorithm can provide a significant aid to harbour protection and can reduce the computational load of surveillance operations.

The concerns are with the calculation of monostatic and bistatic ambiguity function (AF) of a quadrature phase shift keying (QPSK) signal where the pulses are shaped with a root raised cosine (RRC) filter. The monostatic and bistatic modified Cramer-Rao lower bounds (MCRLBs) for the estimation of target range and velocity are also derived and analysed. The QPSK modulation is used in the downlink of a universal mobile telecommunications system (UMTS) base station, hence the results of our analysis provide a useful tool to asses the performance of a passive coherent location (PCL) system where the non-co-operative transmitter of opportunity is a UMTS base station. The actual growing coverage of UMTS signals on the international territory makes multistatic radar configuration feasible, therefore these results can also be exploited for the dynamical selection of the transmitter in a multistatic radar system where multiple UMTS base stations are used.

This paper concerns with the identifiability of a vector of unknown deterministic parameters. In many practical applications, the data model is affected by additional random parameters whose estimation is not strictly required, the so-called nuisance parameters. In these cases, the classical definition of identifiability, which requires the calculation of the Fisher Information Matrix (FIM) and of its rank, is often difficult or impossible to perform. Instead, the Modified Fisher Information Matrix (MFIM) can be computed. We generalize the main results on the identifiability problem to take the presence of random nuisance parameters into account. We provide an alternative definition of identifiability that can be always applied but that is weaker than the classical definition, and we investigate the relationships between the identifiability condition and the MFIM. Finally, we apply the obtained results to the identifiability in presence of nuisance parameters to the relative grid-locking problem for netted radar system.

The purpose of this chapter is to introduce geometric aspects of waveform diversity in terms of bistatic ambiguity function (BAF) and Cramer-Rao lower bounds (CRLBs). These aspects are fundamental in the choice of bistatic channel or set of channels in multistatic systems for target kinematic parameters estimation. Exploiting the relation between the ambiguity function (AF) and the CRLB, it is possible to calculate the bistatic CRLBs of target range and velocity of each transmitter-receiver (TX-RX) pair as a function of the target kinematic parameters and to provide a local measure of the estimation accuracy of these parameters. The information gained through the calculation of the bistatic CRLBs can also be used to evaluate the performance of each channel of the multistatic system and therefore for the choice, along the trajectory of the target, of the optimum TX-RX pair (or a set of bistatic channels) for data fusion and target tracking. This chapter proposes an algorithm that specifies what channels should be discarded and what channels should be considered during the fusion process. The results shown here can also be used [1] to calculate the weighting coefficients for combining the signals arising from the sensors of the network, highlighting those sensors exhibiting the best performance and discarding those channels with the worst one.

In this work, we propose a distributed power control algorithm able to capture the tradeoff between detection capabilities and power consumption for a radar sensor network. This is achieved by modeling the radar sensors as rational agents engaging in a noncooperative game in which the detection threshold and the transmit power are properly designed according to the Nash equilibrium solution. An iterative algorithm based on a best-response dynamics is proposed to achieve the equilibrium point and its performance is compared to that achieved by a uniform power allocation.

Circadian rhythms of hypothalamic catecholamines and their metabolites and of prolactin and corticosterone circulating hormones were determined over 24 h in group-housed (six per cage; control) and individually housed, 90-day-old male albino rats adapted to a 12:12 light/dark cycle. After 5 weeks of adaptation, in individually housed rats, norepinephrine (NE) turnover increased, since lower NE (p < 0.01) and higher MOPEG metabolite (p < 0.01) levels were measured. As concerns the dopaminergic system, individually housed rats increased both dopamine (DA) synthesis and turnover as revealed by higher DOPAC (p < 0.01) and HVA (p < 0.05) metabolites without modification of DA levels. Moreover, in individually housed rats, corticosterone (p < 0.01) and prolactin (p < 0.05) mean levels were higher than in the control group.