Miracle-dz/UniFAR-FTUs huggingface dataset:
Numerical Simulations of Photoluminescence for the Precise Determination of Emitter Contact Recombination Parameters

One major loss mechanism for currently relevant solar cells [e.g., passivated emitter and rear cells (PERC)] is locally enhanced recombination at the interface between semiconductor and metalization. For investigating these losses in detail, a reliable detection technique is crucial. The photovoltaics community frequently applies an area-weighted model to extract the local dark saturation current density in the metalized area of the emitter j0,met—e.g., from photoluminescence imaging (PLI) data. However, this model does not account for the nonuniformity of the excess carrier density Δn within the sample during the measurement. Therefore, we compare numerical PLI simulations using Quokka3 to PLI measurements, to quantitatively reveal the impact of the nonuniformity of Δn. Test structures with locally laser-ablated passivation on one side—serving as ideal test structures—are used for the experimental verification. Additionally, we show results on metalized samples. We find that the results (j0,met*) using the simulative approach for the laser-ablated samples exceed the results using the conventional area-weighted approach by more than 20%. For the metalized samples, we see a similar trend where the area-weighted approach again underestimates the results (j0,met), in this case by up to 20%. Based on our investigations, we show that the deviation between the results arises due to the assumption of uniform Δn applied by the area-weighted approach.
The fourth order diffusion model for a bi-flux mass transfer

A abordagem discreta e empregada para a difusao com retencao para obter a equacao de quarta ordem, o que sugere a introducao de um segundo fluxo levando a associacao da teoria bi-fluxo com novos parâmetros: fracao β e coeficiente de reatividade R. O objetivo desta tese e explorar a Embora comparando o comportamento da concentracao e os dois fluxos com o modelo classico, principalmente pelo metodo de elementos finitos de Galerkin. Mostra-se que o processo pode ser acelerado ou retardado dependendo da relacao entre R e β, para o meio isotropico. Dependendo da definicao do segundo fluxo em funcao desses parâmetros e da relacao β= β(R), o comportamento inesperado aumentando a concentracao logo apos a introducao de um impulso inicial que se opoe a tendencia natural de dispersao, pode se desenvolver em uma recuperacao restrita. O coeficiente de reatividade R considerado como um atrator variando no espaco e no tempo de acordo com uma lei de difusao e proposto para simular caixa de nutrientes atraindo particulas biologicas. Finalmente, sao apresentados dois casos tipicos de difusao nao-linear que representam dinâmicas de reacoes quimicas. O modelo bi-fluxo tende a regularizar as solucoes.
Exploiting Channel Correlations for NLOS ToA Localization With Multivariate Gaussian Mixture Models

In this letter, we develop a Bayesian probabilistic approach for time-of-arrival (ToA) localization in non-line-of-sight (NLOS) channels, where multivariate Gaussian mixture models (GMM) are used to approximate the joint distribution of channel bias values and harness the channel correlations. Using over-the-air measurements from a proprietary localization system, we numerically demonstrate that the proposed algorithm outperforms both a counterpart Bayesian probabilistic approach that does not take into account channel correlations and the well-known non-linear least square (NLS) optimization method.
The Kelly Growth Optimal Portfolio with Ensemble Learning

As a competitive alternative to the Markowitz mean-variance portfolio, the Kelly growth optimal portfolio has drawn sufficient attention in investment science. While the growth optimal portfolio is theoretically guaranteed to dominate any other portfolio with probability 1 in the long run, it practically tends to be highly risky in the short term. Moreover, empirical analysis and performance enhancement studies under practical settings are surprisingly short. In particular, how to handle the challenging but realistic condition with insufficient training data has barely been investigated. In order to fill voids, especially grappling with the difficulty from small samples, in this paper, we propose a growth optimal portfolio strategy equipped with ensemble learning. We synergically leverage the bootstrap aggregating algorithm and the random subspace method into portfolio construction to mitigate estimation error. We analyze the behavior and hyperparameter selection of the proposed strategy by simulation, and then corroborate its effectiveness by comparing its out-of-sample performance with those of 10 competing strategies on four datasets. Experimental results lucidly confirm that the new strategy has superiority in extensive evaluation criteria.
Aspectos Gramaticais da Língua KA'APOR

O estudo intitulado Aspectos gramaticais da lingua Ka'apor tem como objetivo analisar alguns fenomenos gramaticais dessa lingua. Num primeiro momento, investigo a fonologia e morfologia. Na fonologia, descrevo os fonemas vocalicos e consonantais por meio dos fones em oposicao, em distribuicao complementar e variacao. Na morfologia, considero o estatuto gramatical dos prefixos relacionais - {r- O-} e {i- h- O-} e a estrutura morfologica do verbo. Com relacao aos prefixos relacionais, investigo sua ocorrencia nos nomes, sintagmas de posse, sintagmas posposicionais e nos verbos estativos. Ja na estrutura morfologica do verbo, analiso os prefixos de concordância, {a- "eu", re~ ere~e-"tu", ja- "nos", pe- "vos", o-/u- ~ O- "ele, ela(s), o pessoal"}, ps prefixos de alteracao de valencia {mu-} e {ju-}, e o sufixo de negacao {-? im}. Na segunda parte desse trabalho, faco a analise de tres aspectos morfossintaticos do Ka'apor. Trato da expressao da gradacao e quantificacao. Em seguida, analiso as propriedades morfossemânticas do clitico [. kE]. E termino, investigando o alinhamento nos predicados verbais e propondo quatro tipos de alinhamentos, a saber: nominativo-absolutivo; ergativo paciente; intransitivo fluido e neutro. Na ultima parte desse trabalho, dedico a analise da ordem dos constituintes. Mais especificamente, analiso a relacao de ordem entre o nome e seus determinantes (adjetivos, pronomes demonstrativos, pronomes possessivos, numerais, cliticos quantificadores - [.ta] e [.upa] - e o clitico [.kE]), e a ordem nas oracoes declarativas, subordinadas e interrogativas. Nessa analise da lingua Ka'apor foram utilizados os corpora de Kakumasu (1990;1989; 1986); Correa da Silva (1997); Caldas (2001); Silva (2001) e as narrativas dos cursos de documentacao de historias orais realizados nos meses de julho e agosto de 2006 e janeiro de 2008.
Fractional-order robust model reference adaptive control of piezo-actuated active vibration isolation systems using output feedback and multi-objective optimization algorithm

Improving the control performance of active vibration isolation systems is crucial to provide an ultra-quiet environment for precision instruments. This paper presents a new fractional-order robust model reference adaptive controller for the piezo-actuated active vibration isolation systems with a relative-degree-one model. One advantage of the proposed controller lies in that its controller parameters are adjusted online by fractional proportional–integral-type adaptive laws, which not only speeds up the convergence of the closed-loop system, but also improves the control energy efficiency. Moreover, the proposed controller only uses the measurable input and output of the plant as feedback signals, which is convenient for controller implementation. The stability of the closed-loop system is proved based on the Lyapunov theory in detail. The optimal values of the fractional order and adaptive gains for adaptive laws are determined using the multi-objective genetic algorithm through off-line simulation. Comparative experiments on the piezo-actuated active vibration isolation systems are conducted to verify the effectiveness of the proposed controller. Results show that the proposed controller achieves satisfactory isolation performance in a wider frequency band of 20–500 Hz, and simultaneously reduces the control effort compared with the traditional MRAC methods.
Influence of Fluid-Structure Interaction on Human Eye Biomechanics Under Air Puff Non-Contact Tonometry

Biomechanical properties of biological tissues are important health indicators and multiple clinical decisions and surgical planning can be made based on their dynamic response to loading. But until now, some of the mechanical and dynamic responses are not fully understood due to the non-linearity and viscoelastic behaviour of biological tissues. The relevant biological tissues of interest in the current study are the cornea and sclera of the human ocular globe. Cornea contributes with two-thirds of the optical focusing power of the eye beside intraocular lens and ocular fluids. The air puff tonometry test is a non-contact method with direct interaction to cornea in order to estimate the intraocular pressure which helps with early Glaucoma diagnosis. The gab in research of this area is considering the fluid-structure interaction effect between cornea, the air puff and the eye internal fluid. Numerical model of the air puff test was constructed in the context of a coupled model between computational fluid dynamics (CFD) and finite element analysis (FEA) using Arbitrary Lagrangian-Eulerian (ALE) deforming mesh. The time span of the jet is 30 ms and maximum Reynolds number (Re = 2.3×104), with jet orifice diameter 2.4 mm and impinging distance 11 mm. The present study was the first to take fluid-structure interaction between the air puff and cornea into account, in IOP and cornea material behaviour estimations.
AN EVALUATION OF THE FACTORS AFFECTING THE USE OF ICT IN SECONDARY SCHOOLS MANAGEMENT IN KENYA: A CASE OF NAROK COUNTY.

The purpose of this study was to determine whether there existed a relationship between three selected ICT variables and management of secondary schools in Narok County in Kenya. The selected variables that were used in the study included IT literacy level, accessibility of internet or internet enabled devices and awareness in ICT usage. Quantitative research methodology was used under the umbrella of survey research design. Purposeful sampling strategy was used to select 240 parents (4 parent representatives from forms 1-4) as accessible population for the study. Questionnaires were used to collect data from parents in Narok County. A Cronbach’s alpha index was used to check reliability which was found to be . 76 for all items used. Collected data were analyzed using Pearson’s correlation coefficient with the help of Statistical Package for Social Sciences (SPSS). The findings of the analysis of data revealed that there exists a relationship between literacy of the clients, accessibility of internet by clients and level of awareness of ICT and principals management using ICT in secondary schools in Narok County. The findings revealed that the use of ICT was a
Propagation speed of inertial waves in cylindrical swirling flows

Thermo-acoustic combustion instabilities arise from feedback between flow perturbations and the unsteady heat release rate of a flame in a combustion chamber. In the case of a premixed, swirl stabilized flame, an unsteady heat release rate results from acoustic velocity perturbations at the burner inlet on the one hand, and from azimuthal velocity perturbations, which are generated by acoustic waves propagating across the swirler, on the other. The respective time lags associated with these flow–flame interaction mechanisms determine the overall flame response to acoustic perturbations and therefore thermo-acoustic stability. The propagation of azimuthal velocity perturbations in a cylindrical duct is commonly assumed to be convective, which implies that the corresponding time lag is governed by the speed of convection. We scrutinize this assumption in the framework of small perturbation analysis and modal decomposition of the Euler equations by considering an initial value problem. The analysis reveals that azimuthal velocity perturbations in swirling flows should be regarded as dispersive inertial waves. As a result of the restoring Coriolis force, wave propagation speeds lie above and below the mean flow bulk velocity. The differences between wave propagation speed and convection speed increase with increasing swirl. A linear, time invariant step response solution for the dynamics of inertial waves is developed, which can be approximated by a concise analytical expression. This study enhances the understanding of the flame dynamics of swirl burners in particular, and contributes physical insight into the inertial wave dynamics in general.
Climate Change: Models, Metrics and Meaning Making

This thesis, combining research in climate science and educational science, investigates different aspects of climate knowledge. It consists of five papers and covers three major topics: emission metrics, public understanding of atmospheric CO2 accumulation, and spatial modelling of natural resource use. In Paper I-II, we study emission metrics that compare the climate impact of different climate forcers in two different ways. For Paper I, we use Sea Level Rise (SLR) as the basis for comparison, proposing two novel emission metrics. We find that all examined climate forcers – even short-lived – have considerable influence on SLR on at least a century time scale. Paper II focuses on how the Climate-Carbon cycle Feedback (CCF) affects emission metric values, in relation to how the CCF caused by non-CO2 forcers is modeled. For emission pulses, we show that with an approach previously used to calculate climate metrics using linear feedback analysis for the CCF, the effect of it will persist basically forever, while with an approach based on an explicit carbon cycle model, the CCF effect by non-CO2 forcers eventually vanishes, leading to lower metric values for longer time-horizons. Paper III-IV, related to climate science literacy, focus on public understanding of atmospheric CO2 accumulation and its potential link to climate policy support. In Paper III, we identified five qualitatively different ways of reasoning about CO2 accumulation; only one of these is consistent with mass balance principles. We also found that task formulation has a strong bearing on the assessment of understanding, but that strong climate policy support does not require that people can solve typical CO2 tasks. In Paper IV, we draw attention to a range of challenges that university students experience when reasoning about CO2 accumulation, ranging from cognitive to metacognitive and affective challenges. Most notable for the cognitive domain was the failure to understand how uptake of CO2 depends on emission pathways. In Paper V, we model low-income villagers’ spatial natural resource use while removing constraining assumptions on villagers’ behaviour. We find that removing commonly used constraints lead to higher degrees of heterogeneity among villagers’ spatial behaviour, especially for intermediate distance cases.
Facial Expression Recognition: A Survey

Facial Expression Recognition (FER), as the primary processing method for non-verbal intentions, is an important and promising field of computer vision and artificial intelligence, and one of the subject areas of symmetry. This survey is a comprehensive and structured overview of recent advances in FER. We first categorise the existing FER methods into two main groups, i.e., conventional approaches and deep learning-based approaches. Methodologically, to highlight the differences and similarities, we propose a general framework of a conventional FER approach and review the possible technologies that can be employed in each component. As for deep learning-based methods, four kinds of neural network-based state-of-the-art FER approaches are presented and analysed. Besides, we introduce seventeen commonly used FER datasets and summarise four FER-related elements of datasets that may influence the choosing and processing of FER approaches. Evaluation methods and metrics are given in the later part to show how to assess FER algorithms, along with subsequent performance comparisons of different FER approaches on the benchmark datasets. At the end of the survey, we present some challenges and opportunities that need to be addressed in future.
A Visual Servoing Approach for Robotic Fruit Harvesting in the Presence of Parametric Uncertainties

In this paper, we address the robust visual servoing problem for a fixed target using an eyein-hand camera configuration, when the camera calibration parameters are uncertain. The proposed solution combines the image-based visual servoing (IBVS) and the position-based visual servoing (PBVS) approaches to take advantage of both strengths to perform successful robotic fruit harvesting tasks. An image-based detection and recognition method, based on SURF and RANSAC algorithms, is used to extract the image feature of the fruit for the vision-based control algorithm. A kinematic control design, with robustness properties, is employed to cope with the uncertainties in the calibration parameters of the camera-robot system. To deal with possible singular configurations of the robot arm, that may arise during the task execution, we employ the Damped Least-Squares (DLS) inverse method. Experimental results, obtained with a Mitsubishi robot arm RV-2AJ carrying out strawberry harvesting tasks, are included to illustrate the performance and feasibility of the proposed methodology. Keywords— Visual Servoing, Agricultural Robots, Automatic Fruit Harvesting, Kinematic Control. Resumo— Neste trabalho, considera-se o problema de servovisão robusta para um alvo fixo usando uma configuração de câmera eye-in-hand, quando os parâmetros de calibração da câmera são incertos. A solução proposta combina as abordagens de servovisão baseada em imagem e servovisão baseada em posição utilizando suas principais vantagens para realizar tarefas bem-sucedidas de colheita robótica de frutas. Um método de detecção e reconhecimento de imagem, baseado nos algoritmos SURF e RANSAC, é usado para extrair a caracteŕıstica da imagem da fruta. Um algoritmo de controle cinemático, com propriedades de robustez, é empregado para lidar com as incertezas nos parâmetros de calibração do sistema câmera-robô. Para lidar com posśıveis configurações singulares do braço robótico, que podem surgir durante a execução da tarefa, utiliza-se o método Damped Least-Squares (DLS) inverso. Resultados experimentais, obtidos com um robô manipulador Mitsubishi RV-2AJ executando tarefas de coleta de morangos, são inclúıdos para ilustrar o desempenho e a viabilidade da metodologia proposta. Palavras-chave— Servovisão, Robôs Agŕıcolas, Coleta de Frutas Autômática, Controle Cinemático.
Contact Angle Profiles for Droplets on Omniphilic Surfaces in the Presence of Tangential Forces

In real life, sessile droplets usually have a three-dimensional shape, making it difficult to understand their forced wetting behavior, both from an experimental and a theoretical perspective. Even in the case of spreading under quasi-static conditions, where the droplet shape is described by the Young–Laplace equation, there is no fundamental approach to describe the contact line evolution. In the present work, a few existing approaches on this issue are analyzed and assessed. It is shown that an experimentally inspired fixed shape for the contact line of droplets that are spreading under the action of tangential forces can be considered equivalent to a theory for contact line motion. There is a lack of experimental data for contact line evolution under arbitrary scenarios of forces. Such data will be very helpful for the further development of the suggested approach to contact line motion. Of particular interest is the case of small contact angle droplets, for which a top view can clearly indicate the contact line location. On the contrary, in such droplets, the direct experimental measurement of contact angle profile is very difficult. This must be estimated theoretically; thus, a special approach has been developed here for this purpose.
Fault detection filter design for interval type-2 fuzzy systems under a novel adaptive event-triggering mechanism

ABSTRACT This study is concerned with the problem of event-based fault detection (FD) filter design for interval type-2 fuzzy systems in a network environment. Firstly, by employing the properties of exponential function, a novel adaptive event-triggering mechanism (AETM) where the boundedness of threshold function is guaranteed and the size of threshold function is inversely proportional to the size of 2-norm of the sampled-output-error is proposed to dynamically adapt the variation of the system and to reduce the unnecessary information communication between the sensor and the filter. Secondly, in the framework of time-delay systems, the FD system with a networked filter and an AETM is modelled as an interval time-varying delayed system. Then, a sufficient condition to implement co-design of the parameters of filter and trigger is obtained by applying a simple Lyapunov–Krasovskii functionals, combined with recently developed Wirtinger-based integral inequality and reciprocally convex inequality, and utilising congruent transformation method. Thirdly, based on the obtained co-design condition, an optimisation algorithm subject to convex constraints for the tradeoffs between resource utilisation and performance of the FD system is further developed. Finally, two numerical examples are provided to demonstrate the effectiveness of the proposed scheme.
Heart Rate Dynamics in Patients with Obstructive Sleep Apnea: Heart Rate Variability and Entropy

Background: Obstructive sleep apnea (OSA), a highly prevalent sleep disorder, is closely related to cardiovascular disease (CVD). Our previous work demonstrated that Shannon entropy of the degree distribution (EDD), obtained from the network domain of heart rate variability (HRV), might be a potential indicator for CVD. Method: To investigate the potential association between OSA and EDD, OSA patients and healthy controls (HCs) were identified from a sleep study database. Then EDD was calculated from electrocardiogram (ECG) signals during sleep, followed by cross-sectional comparisons between OSA patients and HCs, and longitudinal comparisons from baseline to follow-up visits. Furthermore, for OSA patients, the association between EDD and OSA severity, measured by apnea-hypopnea index (AHI), was also analyzed. Results: Compared with HCs, OSA patients had significantly increased EDD during sleep. A positive correlation between EDD and the severity of OSA was also observed. Although the value of EDD became larger with aging, it was not OSA-specified. Conclusion: Increased EDD derived from ECG signals during sleep might be a potential dynamic biomarker to identify OSA patients from HCs, which may be used in screening OSA with high risk before polysomnography is considered.
Development a Software with Augmented Reality Using Unreal Engine 4

— We are live in a time where technology take a big part in our life. To use technology we need to interact with them using interfaces. There are a lot of hardware manipulators like keyboard, joystick, microphone and programm manipulators like button, textfield, media player, etc. But one of the most interesting is augmented reality. It help us to develop not just a simple application or a game but an application that interacts with a whole real world and opens user a new beautiful mix of real and virtual world.