17,294 research outputs found
In-Vivo Skin Capacitive Image Classification Using AlexNet Convolution Neural Network
© 2018 IEEE. Skin water content is very important for its cosmetic properties and its barrier functions, however, to measure it is very difficult. We have recently developed a novel hand-held probe for in-vivo skin hydration imaging based on the capacitance measurement principle. It is more repeatable, reproducible and easier to calibrate than the existing commercial devices. Our latest research is to assess the performance of deep learning in in-vivo skin capacitive image analysis using AlexNet model. As we know the AlexNet model can be used for image classification and recognition with high accuracy. Our object is to design a model to classify more than one specific features, i.e. not just the one with highest probability. We trained the image classifier using the pretrained model to implement the specific feature extraction, prediction and classification specifically for the skin hydration level, skin damage level and gender. There are over 1000 skin images which are measured by two experiments: repeatability of different instruments in in-vivo skin measurement; and skin damage measurements by different instruments. The objective of the research has been divided into three parts: feature extraction implementation using the pretrained model AlexNet; accuracy assessment of the model; further improve the system for multiple features classification. The image classification programme shows a good result which has accuracy 0.98, and the test images were classified correctly comparing with the experimental results of skin hydration, skin damaged level and the gender of the volunteers
Skin Image Retrieval Using Gabor Wavelet Texture Feature
OBJECTIVE: Skin imaging plays a key role in many clinical studies. We have used many skin imaging techniques, including the recently developed capacitive contact skin imaging based on fingerprint sensors. The aim of this study is to develop an effective skin image retrieval technique using Gabor wavelet transform, which can be used on different types of skin images, but with a special focus on skin capacitive contact images. METHODS: Content-based image retrieval (CBIR) is a useful technology to retrieve stored images from database by supplying query images. In a typical CBIR, images are retrieved based on colour, shape, and texture, etc. In this paper, texture feature is used for retrieving skin images, and Gabor wavelet transform is used for texture feature description and extraction. RESULTS: The results show that the Gabor wavelet texture features can work efficiently on different types of skin images. Although Gabor wavelet transform is slower compared with other image retrieval techniques, such as Principal Component Analysis (PCA) and Grey level co-occurrence matrix (GLCM), Gabor wavelet transform is the best for retrieving skin capacitive contact images and facial images with different orientations. Gabor wavelet transform can also work well on facial images with different expressions and skin cancer/disease images. CONCLUSION: We have developed an effective skin image retrieval method based on Gabor wavelet transform, that it is useful for retrieving different types of images, namely digital colour face images, digital colour skin cancer and skin disease images, and particularly, grayscale skin capacitive contact images. Gabor wavelet transform can also be potentially useful for face recognition (with different orientation and expressions) and skin cancer/disease diagnosis. This article is protected by copyright. All rights reserved
Nodeless superconductivity in Ca3Ir4Sn13: evidence from quasiparticle heat transport
We report resistivity and thermal conductivity measurements
on CaIrSn single crystals, in which superconductivity with K was claimed to coexist with ferromagnetic spin-fluctuations. Among
three crystals, only one crystal shows a small hump in resistivity near 20 K,
which was previously attributed to the ferromagnetic spin-fluctuations. Other
two crystals show the Fermi-liquid behavior at low temperature.
For both single crystals with and without the resistivity anomaly, the residual
linear term is negligible in zero magnetic field. In low fields,
shows a slow field dependence. These results demonstrate that
the superconducting gap of CaIrSn is nodeless, thus rule out
nodal gap caused by ferromagnetic spin-fluctuations.Comment: 5 pages, 4 figure
Effect of Electric and Stress Field on Structures and Quantum Conduction of Cu Nanowires
The ballistic transport properties of Cu nanowires under different electric and stress fields are investigated for future application in microelectronics using first-principles density-function theory. Relative to the case with the electric field only, the stability and quantum conduction of both nonhelical and helical atomic strands are enhanced by applying a stress field F. Under V = 1 V/Å, the most excellent quantum conductivity is exhibited at F = 1.5 nN for the nonhelical atomic strands while at F = 2 nN for the helical ones, and the latter is more stable with collapse-resistant F high as 3 nN compared to the former as 2 nN
Ecosystem evolution mechanism of manufacturing service system driven by service providers
This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this record.To date, research has mainly discussed the definition and classification of producer services. Yet many companies require an integrated solution of products and producer services. The aim of this paper is to propose a model of the ecological evolution of manufacturing service systems (MSS) driven by service providers. This model adopts modular thinking to integrate dispersive producer services into an entire MSS, the process of which forms the ecological evolution of MSS. This paper applies ecological theory to build the ecological evolution mechanism of MSS. In this mechanism, the predator–prey relationship is used as a metaphor for the relationships between manufacturers and service providers in a MSS. A predator–prey model is built to simulate the ecological evolution of MSS. A predation cellular genetic algorithm is adopted to optimise this evolution. The proposed model and algorithm are demonstrated and validated by a case study of MSS in bicycle industry. This study contributes to theory by proposing and clarifying the mechanism for provision of services between businesses. The future research will focus on the application and empirical analysis of this mechanism derived from big data.This work has been supported by the National Natural Science Foundation of China [grant number 51205353], [grant number 71571161], [grant number 51475434]
Lattice Boltzmann Approach to High-Speed Compressible Flows
We present an improved lattice Boltzmann model for high-speed compressible
flows. The model is composed of a discrete-velocity model by Kataoka and
Tsutahara [Phys. Rev. E \textbf{69}, 056702 (2004)] and an appropriate
finite-difference scheme combined with an additional dissipation term. With the
dissipation term parameters in the model can be flexibly chosen so that the von
Neumann stability condition is satisfied. The influence of the various model
parameters on the numerical stability is analyzed and some reference values of
parameter are suggested. The new scheme works for both subsonic and supersonic
flows with a Mach number up to 30 (or higher), which is validated by well-known
benchmark tests. Simulations on Riemann problems with very high ratios
() of pressure and density also show good accuracy and stability.
Successful recovering of regular and double Mach shock reflections shows the
potential application of the lattice Boltzmann model to fluid systems where
non-equilibrium processes are intrinsic. The new scheme for stability can be
easily extended to other lattice Boltzmann models.Comment: Figs.11 and 12 in JPEG format. Int. J. Mod. Phys. C (to appear
Data driven discovery of cyber physical systems
Abstract: Cyber-physical systems embed software into the physical world. They appear in a wide range of applications such as smart grids, robotics, and intelligent manufacturing. Cyber-physical systems have proved resistant to modeling due to their intrinsic complexity arising from the combination of physical and cyber components and the interaction between them. This study proposes a general framework for discovering cyber-physical systems directly from data. The framework involves the identification of physical systems as well as the inference of transition logics. It has been applied successfully to a number of real-world examples. The novel framework seeks to understand the underlying mechanism of cyber-physical systems as well as make predictions concerning their state trajectories based on the discovered models. Such information has been proven essential for the assessment of the performance of cyber-physical systems; it can potentially help debug in the implementation procedure and guide the redesign to achieve the required performance
The occlusion effects in capacitive contact imaging for in vivo skin damage assessments.
OBJECTIVE: The aim of this study was to investigate the occlusion effects in capacitive contact imaging, and to develop a new quantitative methodology for in vivo skin assessments using capacitive contact imaging and condenser-TEWL (transepidermal water loss) method. METHODS: Two measurement technologies were used in this study, i.e., capacitive contact imaging and condenser-TEWL method. Three types of skin damages were studied, intensive washes, tape stripping and sodium lauryl sulphate (SLS) irritation. The test skin sites were chosen on the volar forearms of healthy volunteers (aged 25-45); the measurements were taken both before and periodically after the damages. RESULTS: The results show that the time-dependent occlusion curves of the capacitive contact imaging can reflect the types of damages, and by analysing the shapes of the curves, we can get information about the skin surface water content level and stratum corneum thickness. The results also show that the combination of capacitive contact imaging and condenser-TEWL method gives extra information about the skin damages, such as the types of the damages and status of the damages. CONCLUSION: We have developed a potential new quantitative methodology for skin damage assessments using capacitive contact imaging and condenser-TEWL method. The combination of the two technologies can provide useful information for skin damage assessments. We have also developed a mathematical model for analysing the occlusion curves
A comparison of five extraction methods for extracellular polymeric substances (EPS) from biofilm by using threedimensional excitation-emission matrix (3DEEM) fluorescence spectroscopy
Two physical methods (centrifugation and ultrasonication) and 3 chemical methods (extraction with EDTA, extraction with formaldehyde, and extraction with formaldehyde plus NaOH) for extraction of EPS from alga-bacteria biofilm were assessed. Pretreatment with ultrasound at low intensity doubled the EPS yield without significant modification of the composition of EPS. Extraction with EDTA or extraction with formaldehyde plus NaOH increased yield by about 1 order of magnitude compared with other methods. However, the protein and polysaccharide content in EPS prepared with EDTA or formaldehyde plus NaOH were low. Two fluorescence peaks belonging to protein-like peaks and 2 fluorescence peaks belonging to humic acid-like substances were found in 3DEEM fluorescence spectra of all the EPS samples prepared using different methods. Fulvic-like fluorescence was detected only in the EPS extracted with formaldehyde plus NaOH. Location of, and fluorescence intensity at, each peak were clearly affected by the extraction methods. Dialysis was also found to be an important factor influencing the yield, composition and fluorescence characteristics of EPS.Keywords: biofilm, extracellular polymeric substances, 3DEEM fluorescence spectroscop
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