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- 摘要
- 关键词
- 实验方案
- 产品
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Total Global Solar Radiation Estimation with Relative Humidity and Air Temperature Extremes in Ireland and Holland
摘要： Solar radiation is the earth’s primary energy source for all biochemical and physical activities. Accurate knowledge of the solar radiation is important in engineering applications. This study aimed to calibrate some of the existing models in the literature for estimating daily total global solar radiation parameter using available measuring records (maximum and minimum air temperatures) and new models were developed based on maximum and minimum air temperatures, relative humidity and relative humidity extremes. Applicability of the Hargreaves model, Allen model, Bristow-Campbell model and Chen model were evaluated for computing the daily total solar global radiation, the geographical and meteorological data of Irish and Dutch cities were used. Meteorological data were taken from Royal Netherlands Meteorological Institute and Irish Meteorological Service. The models were compared on the basis of error tests which were mean percentage error (MPE), mean bias error (MBE), root mean square error (RMSE) and Nash-Sutcliffe equation (NSE). And, monthly MPE errors were given for each model. This study proposed new estimation models which were based on daily average relative humidity, relative humidity extremes and temperature extremes. Error analyses were applied to these models and results were given in the study.
关键词： Holland,solar radiation,model validation,temperature,daily total global solar radiation,relative humidity,model comparison,Ireland,meteorological models
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE 27th Asian Test Symposium (ATS) - Hefei, China (2018.10.15-2018.10.18)] 2018 IEEE 27th Asian Test Symposium (ATS) - Test Diagnosis of Digital Microfluidic Biochips Using Image Segmentation
摘要： Digital micro?uidic biochip has been developed as a promising alternative to the traditional approach of benchtop laboratory tests. Dependability is an important biochemical attribute for micro?uidic biochips that are used for safety-critical applications, such as point-of-care health assessment, air-quality monitoring, and food-safety testing. Therefore, the robust of?ine and online test techniques are required after manufacturing and during bioassay operations. In this work, we are presenting an image segmentation based testing methodology to detect the catastrophic faults and to locate the faulty cells. The design-for diagnosability scheme is proposed, and it is shown that faults can be located and tolerated by providing alternative paths in biochips. Moreover this testing method also facilitates the testing of a biochip with other bioassay operations running concurrently.
关键词： fault models,CCD,Biochip,electrowetting,image segmentation,test time
更新于2025-09-04 15:30:14
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Organ- on -a- chip technologies that can transform ophthalmic drug discovery and disease modeling
摘要： Introduction: Disorders of the eye that lead to visual impairment are affecting millions of people worldwide. Nevertheless, for many of these disorders, there are still no effective treatment options available due to the lack of in vitro model systems that emulate the physiological in vivo structure and function of human eyes. Microphysiological organ-on-a-chip (OoC) technology represents a novel and powerful approach to overcome the limitations of conventional model systems and lead to a paradigm shift in ophthalmic research. Areas covered: This review provides an overview of the various tissues of interest in ophthalmology and summarizes existing model systems, including their applications and limitations. Additionally, novel OoC systems with applications in ophthalmology are described and the advantages of these systems compared to conventional models are highlighted. Expert opinion: The physiological relevance of the first ophthalmic OoC systems that mimic human ocular compartments, such as the cornea and retina, has been successfully demonstrated in recent years. There is a great potential for the application of these platforms for future pharmacological target identification, safety, and efficacy testing, as well as personalized medicine. Further improvements and the development of new systems are of upmost importance, especially to model complex disorders affecting several tissues.
关键词： ophthalmic model,microphysiological system,retina-on-a-chip,ocular model,Cornea-on-a-chip,in-vitro models,organ-on-a-chip
更新于2025-09-04 15:30:14
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Color and brightness encoded in a common L- and M-cone pathway with expansive and compressive nonlinearities
摘要： Lights near 560 nm appear brighter when flickered, whereas lights near 520 or 650 nm appear yellower. Both effects are consistent with signal distortion within the visual pathway—brightness changes at an expansive nonlinearity, and hue shifts at a compressive one. We previously manipulated the distortion products generated by each nonlinearity to extract the temporal properties of stages of the L- and M-cone pathways that signal brightness and color before (early stages) and after (late stages) each nonlinearity. We find that the attenuation characteristics of the early and late stages are virtually identical in both pathways: The early temporal stage acts like a band-pass filter peaking at 10–15 Hz, while the late stage acts like low-pass filter with a cut-off frequency near 3 Hz. We propose a physiologically relevant model that accounts for the filter shapes and incorporates both nonlinearities within a common parvocellular pathway. The shape of the early band-pass filter is consistent with antagonism between center signals and more sluggish and delayed surround signals, while the late filter is consistent with a simple two-stage low-pass filter. Modeling suggests that the brightness change and hue shift are both initially caused by the half-wave rectification and partition of signals into ON and OFF components. However, the hue shift is probably caused by the additional effects of a later nonlinearity that compresses chromatic red and green signals. Plausible sites for the expansive half-wave rectifying nonlinearity are after surround antagonism, possibly from horizontal cells, but the compressive nonlinearity is likely to be after the late filter.
关键词： lightness/brightness,color,nonlinearity,temporal vision,flicker sensitivity,vision models
更新于2025-09-04 15:30:14
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Estimation and validation of daily global solar radiation by day of the year-based models for different climates in China
摘要： Day of the year-based (DYB) models can achieve great accuracy in daily global solar radiation estimation without specific meteorological elements. Many empirical models (EMs) and machine learning (ML) methods have been proposed for DYB models. However, the number of their comparative studies based on diverse climates is limited. In this study, a grand total of 14 DYB models are established to estimate daily global solar radiation based on measured data from 1994 to 2015 at 35 meteorological stations in six climate zones of China. Detailed tasks are as follows: (1) Seven EMs and seven ML models are trained for solar radiation estimation. (2) A new EM and two novel ML models are proposed, i.e. hybrid 3th order polynomial and sine wave model, adaptive neuro-fuzzy inference system (ANFIS) optimized by chaotic firefly algorithm (CFA) and ANFIS optimized by whale optimization algorithm with simulated annealing and roulette wheel selection (WOASAR). (3) Four statistical indicators are utilized to compare those models, and the best model for each station is decided. (4) We discuss the model parameters and climate variances of six specific stations in different climate zones. The comparison results demonstrate superb estimation precision and climate adaptability of the newly proposed models.
关键词： Day of the year,Empirical models,Global solar radiation estimation,Machine learning
更新于2025-09-04 15:30:14
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Comparison of level set models in image segmentation
摘要： Image segmentation is one of the most important tasks in modern imaging applications, which leads to shape reconstruction, volume estimation, object detection and classification. One of the most popular active segmentation models is level set models which are used extensively as an important category of modern image segmentation technique with many different available models to tackle different image applications. Level sets are designed to overcome the topology problems during the evolution of curves in their process of segmentation while the previous algorithms cannot deal with this problem effectively. As a result, there is often considerable investigation into the performance of several level set models for a given segmentation problem. It would therefore be helpful to know the characteristics of a range of level set models before applying to a given segmentation problem. In this study, the authors review a range of level set models and their application to image segmentation work and explain in detail their properties for practical use.
关键词： topology problems,curve evolution,level set models,active segmentation,image segmentation
更新于2025-09-04 15:30:14
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[IEEE 2018 26th European Signal Processing Conference (EUSIPCO) - Roma, Italy (2018.9.3-2018.9.7)] 2018 26th European Signal Processing Conference (EUSIPCO) - New Results on LMVDR Estimators for LDSS Models
摘要： In the context of linear discrete state-space (LDSS) models, we generalize a result lately introduced in the restricted case of invertible state matrices, namely that the linear minimum variance distortionless response (LMVDR) filter shares exactly the same recursion as the linear least mean squares (LLMS) filter, aka the Kalman filter (KF), except for the initialization. An immediate benefit is the introduction of LMVDR fixed-point and fixed-lag smoothers (and possibly other smoothers or predictors), which has not been possible so far. This result is particularly noteworthy given the fact that, although LMVDR estimators are sub-optimal in mean-squared error sense, they are infinite impulse response distortionless estimators which do not depend on the prior knowledge on the mean and covariance matrix of the initial state. Thus the LMVDR estimators may outperform the usual LLMS estimators in case of misspecification of the prior knowledge on the initial state. Seen from this perspective, we also show that the LMVDR filter can be regarded as a generalization of the information filter form of the KF. On another note, LMVDR estimators may also allow to derive unexpected results, as highlighted with the LMVDR fixed-point smoother.
关键词： fixed-lag smoother,fixed-point smoother,Kalman filter,LDSS models,LMVDR estimators
更新于2025-09-04 15:30:14
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A Spectral Assignment-Oriented Approach to Improve Interpretability and Accuracy of Proxy Spectral-Based Models
摘要： In modeling chemical attributes using hyperspectral data, nonlinear relationships between the predictor and the response are frequent. The common nonlinear modeling techniques improve prediction accuracy but suffer from low interpretability of the models. In this paper, we demonstrate a new multivariate modeling method, denoted as spectral assignment-oriented partial least squares (SAO-PLS), which is designed to provide a nonlinear modeling solution with strong interpretability products. The need for this approach is apparent when a given sample population consists of different spectral features for different levels of the response. Accordingly, the suggested SAO-PLS algorithm segments the data in an optimal location on the response distribution by maximizing the difference in spectral assignments between two clusters. SAO-PLS is applied here to two test cases with different characteristics: 1) an established data set containing airborne hyperspectral data of asphaltic roads, merged with in situ measured dynamic friction values captured using a standardized method and 2) a soil spectral library, spectrally measured with an analytical spectral device spectrometer, to which organic carbon measurements were applied. Our results demonstrate the superiority of SAO-PLS over partial least-squares regression for both model accuracy and interpretability, providing a deeper understanding of the underlying processes.
关键词： proxy models,Chemometrics,remote sensing,hyperspectral data,nonlinear modeling
更新于2025-09-04 15:30:14
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Omnidirectional optogenetic stimulation
摘要： Omnidirectional optogenetic stimulation. A wireless, low-power optoelectronic platform, which is based on micro-LEDs, can provide multimodal programmable control over optogenetic stimulation parameters. Optogenetics is a powerful tool for perturbing populations of specific cell types. Here, individual cell types of the central and peripheral nervous systems are tagged with light-sensitive opsins. Specific wavelengths of light can then be used to turn the cells off and on, allowing complex neural circuitry to be dissected. For example, blue light can be used to activate neurons and green light can be used to deactivate neurons depending on the expression of either channelrhodopsin-2 (ChR) or halorhodopsins (Halo), respectively. The technique has been important in elucidating new neural pathways in many preclinical models of disease (including those related to memory, depression, sleep, anxiety, and restoration of vision) and could lead to potential new disease targets.
关键词： wireless,micro-LEDs,optogenetics,disease models,neural circuitry
更新于2025-09-04 15:30:14
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[IEEE 2018 International Conference on 3D Vision (3DV) - Verona (2018.9.5-2018.9.8)] 2018 International Conference on 3D Vision (3DV) - Structure-Aware Shape Synthesis
摘要： We propose a new procedure to guide training of a data-driven shape generative model using a structure-aware loss function. Complex 3D shapes often can be summarized using a coarsely defined structure which is consistent and robust across variety of observations. However, existing synthesis techniques do not account for structure during training, and thus often generate implausible and structurally unrealistic shapes. During training, we enforce structural constraints in order to enforce consistency and structure across the entire manifold. We propose a novel methodology for training 3D generative models that incorporates structural information into an end-to-end training pipeline.
关键词： 3D shape synthesis,generative models,deep learning,structure-aware loss
更新于2025-09-04 15:30:14