659 research outputs found
A Theoretical Approach for Dynamic Modelling of Sustainable Development
No full textThis article presents a theoretical model for a dynamic system based on sustainable development. Due to the relatively absence of theoretical studies and practical issues in the area of sustainable development, Romania aspires to the principles of sustainable development. Based on the concept as a process in which economic, social, political and natural environment are combined in order to sustain planet management, our goal is to promote an economic tool for Romanian decision-makers in order to evaluate scenarios and planning options.sustainable development, economic system, economic development, economic welfare, resources scarcity, natural environment
Sensitivity analysis of DSD retrievals from polarimetric radar in stratiform rain based on the μ–Λ relationship
No full textRaindrop size distributions (DSDs) play a crucial role in quantitative rainfall estimation using weather radar. Thanks to dual polarization capabilities, crucial information about the DSD in a given volume of air can be retrieved. One popular retrieval method assumes that the DSD can be modeled by a constrained gamma distribution in which the shape (μ) and rate (Λ) parameters are linked together by a deterministic relationship. In the literature, μ-Λ relationships are often taken for granted and applied without much critical discussion. In this study, we take another look at this important issue by conducting a detailed analysis of μ-Λ relations in stratiform rain and quantifying the accuracy of the associated DSD retrievals. Crucial aspects of our research include the sensitivity of μ-Λ relations to the temporal aggregation scale, drop concentration, inter-event variability, and adequacy of the gamma distribution model. Our results show that μ-Λ relationships in stratiform rain are surprisingly robust to the choice of the sampling resolution, sample size, and adequacy of the gamma model. Overall, the retrieved DSDs are in a rather decent agreement with ground observations (correlation coefficient of 0.57 and 0.74 for μ and Dm). The main sources of errors and uncertainty during the retrievals are calibration offsets in reflectivity (Zhh) and differential reflectivity (Zdr). Measurement noise and differences in scale between radars and disdrometers also play a minor role. The raindrop concentration (NT) remains the most difficult parameter to retrieve, which can be off by several orders of magnitude. After careful data filtering and removal of problematic Zhh/Zdr pairs, the correlation coefficient for the retrieved NT values remained low, only slightly increasing from 0.12 into 0.24.Atmospheric Remote Sensin
Gender change and stigmatization in late-treated Indonesian children, adolescent, and adult patients with DSD
No full textIn Indonesia clinical management of Disorders of Sex Development (DSD) is challenged by limited knowledge and limited diagnostic and treatment facilities. Prior to this study, most patients remained untreated and grew up with ambiguous bodies and doubts about their gen-der. We investigated patients’ experiences of being raised in ambiguity.
118 Indonesian patients, ages 6 – 41, with 46XX DSD (n=27), 46XY DSD (n=77) and chromosomal DSD (n=14) were compared to 118 control subjects matched for gender, age, and living area. Questionnaires for gen-der identity, gender role behavior and social stigmatiza-tion were translated or designed. The psychometric properties were satisfactory. For patient and control group comparisons, Mann-Whitney U and Fisher’s Exact tests were applied.
The results showed that 7% of the children, 8% of the adolescents and 44% of the adults changed gender, parti-cularly non-diagnosed and non-treated patients with 46XY DSD (81%). 95% of the patients changed gender from female to male, including untreated patients with 46,XX CAH-SV. Compared to control groups, cross-gender role behavior was seen in young girls with 46XX CAH-SV (p=.047) and adolescent girls with different types of DSD (p=.01). In girls with DSD, confusion with gender identity was seen (young girls p=.004; adolescent girls p=.01). Adult men reported past cross-gender role behavior (p=.01) and past problems in gender identification (p=.01) prior to female-to-male gender change.
Children with genital ambiguity (p<.006) and cross gender behavior (p<0.001) and adults with ambiguous
1Diponegoro University, Faculty of Psychology, Semarang, Indonesia Full list of author information is available at the end of the article
bodies (p=.001) and adults who changed gender (p<0.03) suffered stigmatization. Rejection or isolation elicited depression and withdrawal from social activities in girls (p=.002), women (p=.009) and youngsters who had changed gender (p=.02).
We conclude that a high percentage of our patients changed gender. The wish for gender change was parti-cularly seen in patients with progressive masculinization. Patients with DSD who had visible ambiguity in physical and behavioral appearance suffered stigmatization. Teas-ing and rejection led to strong emotional reactions. Early clinical evaluation and treatment, patient and parent edu-cation, and teaching coping strategies will improve qual-ity of life
Gender change and stigmatization in late-treated Indonesian children, adolescent, and adult patients with DSD
No full textIn Indonesia clinical management of Disorders of Sex Development (DSD) is challenged by limited knowledge and limited diagnostic and treatment facilities. Prior to this study, most patients remained untreated and grew up with ambiguous bodies and doubts about their gen-der. We investigated patients’ experiences of being raised in ambiguity.
118 Indonesian patients, ages 6 – 41, with 46XX DSD (n=27), 46XY DSD (n=77) and chromosomal DSD (n=14) were compared to 118 control subjects matched for gender, age, and living area. Questionnaires for gen-der identity, gender role behavior and social stigmatiza-tion were translated or designed. The psychometric properties were satisfactory. For patient and control group comparisons, Mann-Whitney U and Fisher’s Exact tests were applied.
The results showed that 7% of the children, 8% of the adolescents and 44% of the adults changed gender, parti-cularly non-diagnosed and non-treated patients with 46XY DSD (81%). 95% of the patients changed gender from female to male, including untreated patients with 46,XX CAH-SV. Compared to control groups, cross-gender role behavior was seen in young girls with 46XX CAH-SV (p=.047) and adolescent girls with different types of DSD (p=.01). In girls with DSD, confusion with gender identity was seen (young girls p=.004; adolescent girls p=.01). Adult men reported past cross-gender role behavior (p=.01) and past problems in gender identification (p=.01) prior to female-to-male gender change.
Children with genital ambiguity (p<.006) and cross gender behavior (p<0.001) and adults with ambiguous
1Diponegoro University, Faculty of Psychology, Semarang, Indonesia Full list of author information is available at the end of the article
bodies (p=.001) and adults who changed gender (p<0.03) suffered stigmatization. Rejection or isolation elicited depression and withdrawal from social activities in girls (p=.002), women (p=.009) and youngsters who had changed gender (p=.02).
We conclude that a high percentage of our patients changed gender. The wish for gender change was parti-cularly seen in patients with progressive masculinization. Patients with DSD who had visible ambiguity in physical and behavioral appearance suffered stigmatization. Teas-ing and rejection led to strong emotional reactions. Early clinical evaluation and treatment, patient and parent edu-cation, and teaching coping strategies will improve qual-ity of life
Statistical Analysis of Instantaneous Frequency Scaling Factor as Derived from Optical Disdrometer Measurements at VW Bands
No full textSince October 2015, NASA Glenn Research Center (GRC) and the Air Force Research Laboratory (AFRL) have collaboratively operated an RF terrestrial link in Albuquerque, New Mexico to characterize atmospheric propagation phenomena at 72 and 84 GHz. The WV-band Terrestrial Link Experiment (WTLE) consists of coherent transmitters at each frequency on the crest of the Sandia Mountains and a corresponding pair of receivers in south Albuquerque. The beacon receivers provide a direct measurement of the link attenuation, while concurrent weather instrumentation provides a measurement of the atmospheric conditions.Among the available weather instruments is an optical disdrometer which yields an optical measurement of rain rate, as well as droplet size and velocity distributions (DSD, DVD). In particular, the DSD can be used to derive an instantaneous scaling factor (ISF) by which the measured data at one frequency can be scaled to another for example, scaling the 72 GHz to an expected 84 GHz timeseries. Given the availability of both the DSD prediction and the directly observed 84 GHz attenuation, WTLE is thus uniquely able assess DSD-derived instantaneous frequency scaling at the VW-bands. Previous work along these lines has investigated the DSD-derived ISF at Ka and Q-band (20 GHz to 40 GHz) using a satellite beacon receiver experiment in Milan, Italy [1-3]. This work will expand the investigation to terrestrial links in the VW-bands, where the frequency scaling factor is lower and where the link is also much more sensitive to attenuation by rain, clouds, and other atmospheric effects
A critical evaluation of the adequacy of the gamma model for representing raindrop size distributions
No full textThe adequacy of the gamma model to describe the variability of raindrop size distributions (DSD) is studied using observations from an optical disdrometer. Model adequacy is checked using a combination of Kolmogorov–Smirnov goodness-of-fit test and Kullback–Leibler divergence and the sensitivity of the results to the sampling resolution is inves-tigated. A new adaptive DSD sampling technique capable of determining the highest possible temporal sampling resolution at which the gamma model provides an adequate representation of sampled DSDs is proposed. The results show that most DSDs at 30 s are not strictly distributed according to a gamma model, while at the same time they are not far away from it either. According to the adaptive DSD sampling algorithm, the gamma model proves to be an adequate choice for the majority (85.81%) of the DSD spectra at resolutions up to 300 s. At the same time, it also reveals a considerable number of DSD spectra (5.55%) that do not follow a gamma distribution at any resolution (up to 1800 s). These are attributed to transitional periods during which the DSD is not stationary and exhibits a bimodal shape that cannot be modeled by a gamma distribution. The proposed resampling procedure is capable of automatically identifying and flagging these periods, providing new valuable quality control mechanisms for DSD retrievals in disdrometers and weather radars.Atmospheric Remote SensingGeoscience and Remote Sensin
Desplazamiento de hebras de ADN (DSD) como sustrato de hardware para sistemas digitales, analógicos y de aprendizaje automático
No full textHouve um tempo em que a evolução tecnológica de sistemas computacionais era constante e célere. A alta velocidade no desenvolvimento de novas técnicas de miniaturização significava que métodos de fabricação menores e mais eficientes ficavam disponíveis após alguns meses de pesquisa e eram empregados no desenvolvimento de novos circuitos integrados. Embora isso fosse verdade nas últimas décadas, este cenário mudou recentemente devido aos limites impostos pela física. Cada nova geração de dispositivos enfrenta novos desafios de miniaturização dos transistores, principalmente por causa do consumo de energia e dissipação de calor devido à natureza da física quântica nesta escala. À medida que a inteligência artificial se torna mais prevalente devido à necessidade de processar uma enorme quantidade de dados rapidamente em paralelo, o hardware será um gargalo. Várias soluções para este problema de hardware estão sendo propostas e testadas. Algumas delas envolvem o uso de novos paradigmas para construir sistemas computacionais além do silício, tais como o uso de luz ou moléculas orgânicas como substrato para realizar a computação. Uma das alternativas é usar o DNA como hardware "úmido" como um complemento aos computadores tradicionais de silício, acelerando alguns cálculos específicos in vitro ou in vivo. As capacidades de processamento massivamente paralelo e baixo consumo de energia do DNA o tornam a alternativa perfeita para a implementação de novas aplicações biológicas, que vão desde o diagnóstico de doenças a novos medicamentos para o tratamento de várias doenças. Esta tese propõe que a tecnologia de deslocamento de fitas de DNA (DNA Strand Displacement, DSD) é passível de ser utilizada como um substrado de hardware para desenvolvimento de circuitos moleculares modulares digitais, analógicos e de aprendizado de máquina. Assim, para atingir este objetivo, esta tese apresentará a contribuição de novas ferramentas de Computer Aided Design (CAD) desenvolvidas que amparam a modularização, composição, projeto, simulação e validação dos circuitos moleculares baseados em DSD.There was a time when the evolution of computer systems technology was fast and steady. The development rate of new miniaturization techniques was high, meaning that smaller and more efficient fabrication methods became available and employed to develop new integrated circuits after a few months. Although this was true in the past decades, this is no longer true due to physics limits. Each new generation of devices faces transistor miniaturization challenges mainly because of power consumption and heat dissipation due to the nature of quantum physics at this scale. As artificial intelligence becomes more prevalent due to the need to process an enormous amount of data in parallel and fast, the hardware will be a bottleneck. Several solutions to this hardware problem are being proposed and tested. Some of them involve trying new paradigms to build computer systems beyond silicon, such as using light or organic molecules as a substrate to carry out the computation. One of the alternatives is using DNA as ``wet'' hardware to complement the traditional silicon computers, accelerating some specific computations in vitro or in vivo. DNA's massively parallel processing capabilities and low power consumption make it the perfect alternative to implementing new medical applications, ranging from diagnostic of diseases to new drugs to treat various illnesses. This thesis proposes that DNA Strand Displacement (DSD) technology can be a hardware substrate for developing digital, analog, and machine-learning modular molecular circuits. Thus, to achieve this goal, this thesis will present the contribution of new Computer Aided Design (CAD) tools developed that support the modularization, composition, design, simulation, and validation of molecular circuits based on DSD.CNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas GeraisCAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio
Factors influencing Physical Distribution Structure Design
No full textThis thesis studies the factors that influence physical distribution structure design. Distribution Structure Design (DSD) concerns the spatial layout of the distribution channel as well as the location(s) of logistics facilities. Despite the frequent treatment of DSD in supply chain handbooks, an empirically validated conceptual framework of factors is still lacking. This thesis studies DSD inmultiple industry sectors (Fashion, Consumer Electronics, Online Retail) and proposes a conceptual framework.TRAIL Thesis Series no. T2021/28, the Netherlands Research School TRAILTransport and Logistic
Protecting IoT Devices through a Hardware-driven Memory Verification
No full textInternet of things (IoT) devices are appearing in all aspects of our digital life. As such, they have become prime targets for attackers and hackers. An adequate protection against attacks is only possible when the confidentiality and integrity of the data and applications of these devices are secured. State-of-the-art solutions mostly address software and network attacks, but overlook physical/hardware attacks. Such attacks can still exploit software vulnerabilities or even introduce them. In this paper, we present embedded memory security (EMS); it protects against physical tampering of the memory of IoT devices. As a case study, we have equipped a RISC-V based system-on-chip (SoC) with an EMS module. Our experimental results show that EMS successfully can protect the SoC against hardware tampering attacks, while having a low performance overhead.Accepted author manuscriptComputer EngineeringQuantum & Computer Engineerin
Revealing the Secrets of Spiking Neural Networks: The Case of Izhikevich Neuron
No full textSpiking Neural Networks (SNNs) are a strong candidate to be used in future machine learning applications. SNNs can obtain the same accuracy of complex deep learning networks, while only using a fraction of its power. As a result, an increase in popularity of SNNs is expected in the near future for cyber physical systems, especially in the Internet of Things (IoT) segment. However, SNNs work very different than conventional neural network architectures. Consequently, applying SNNs in the field might introduce new unexpected security vulnerabilities. This paper explores and identifies potential sources of information leakage for the Izhikevich neuron, which is a popular neuron model used in digital implementations of SNNs. Simulations and experiments on FPGA implementation of the spiking neurons show that timing and power can be used to infer important information of the internal functionality of the network. Additionally, the paper demonstrates that is feasible to perform a reverse engineering attack using both power and timing leakage.Accepted author manuscriptComputer EngineeringQuantum & Computer Engineerin
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