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Secure medical image steganography through optimal pixel selection by EH-MB pipelined optimization technique
摘要： In today’s world, transmission of information over the channel is not secure for example patient records and other sensitive information. In order to protect this sensitive information, it is coded within the image, audio or text files which is decodable only with the help of a particular key. To enable security to the covert communication and safeguarding the information for securing medical data to avoid medical related cybercrimes, we have proposed a method for medical image steganography using Elephant Herding-Monarch Butterfly (EH-MB) Optimization algorithm for effective selection of pixels for embedding the secret message (i.e. image/text medical report data) in the cover image. Initially, the cover is converted to frequency domain using multilevel DWT, where, the pixel selection is done optimally in the high frequency components using EH-MB algorithm. EH-MB based pixel selection procedure uses a fitness function that depends on the cost function, which calculates the edge, entropy, and intensity of the pixel for evaluating fitness. Simulation was done in the working platform of MATLAB and comparison of the proposed steganography approach was done with the other existing methods in terms of Peak-Signal-to Noise-Ratio and Mean Square Error to prove the effectiveness of the proposed approach.
关键词： Intensity,Elephant herding,Steganography,Object,MSE,PSNR,Entropy,Covert,Segmentation,Edge,Monarch butterfly
更新于2025-09-19 17:15:36
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Simple geometrical modifications for substantial color intensity and detection limit enhancements in lateral-flow immunochromatographic assays
摘要： One of the ongoing challenges in lateral flow Immunochromatographic assays (LFIA), is lowering the limit of detection and enhancing their signal quality, i.e. the color intensity. There are a number of rather costly and complicated processes for this aim, such as the use of functionalized materials/membranes and additional spectroscopic readout units. Nonetheless, there are simple and easy to practice alternatives, to be uncovered by analyzing the essential parameters of immunological reactions. The color intensity of the test line is a function of analytes flow velocity and their reaction rate. Detection pad width and test line position impact the flow velocity and reaction rate kinetics, examined in this paper for the limit of detection (LOD) and test-line color intensity. Firstly, the impact of width on the LOD was examined for human chorionic gonadotropin (pregnancy biomarker). Test line color intensity was measured using five different widths of the detection pad (trapezoidal) and four different test line positions, and the trends observed were explained according to the measured evolution of the velocity along the chromatography paper. With a constant width absorbent pad, LOD was cut by half to 5 mIU/ml by using a narrowing width detection pad, which keeps the wicking velocity higher than normal strips, and compared to them, color intensity increase between 55-150%, depending on the concentration. Nevertheless, a widening detection pad might cut the color intensity up to 150%, compared to normal strips, due to a profound decline of the analyte to ligand ratio at the test line. In addition, adequately sending the test line away from the conjugate pad yields the highest possible color intensity, for up to 400% of increase, in lower concentrations and narrowing test pads. However, further distancing the test line downfalls the color intensity.
关键词： Lateral Flow Immunochromatographic Assays,Trapezoidal Geometry,Limit of Detection,Detection Pad,Capillary Flow Velocity,Porous Medium,Color Intensity,Test Line Displacement
更新于2025-09-19 17:15:36
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[IEEE 2018 International Conference on Platform Technology and Service (PlatCon) - Jeju (2018.1.29-2018.1.31)] 2018 International Conference on Platform Technology and Service (PlatCon) - Classification of Daytime and Night Based on Intensity and Chromaticity in RGB Color Image
摘要： Classification of daytime and night in the color image is a very important task in image processing based on color images acquired from CCTV. Also, weather classification must be performed before performing image processing such as weather report, shadow removal and fog detection. In this paper, we proposed the classification, whether a color image is daytime or night. We first set the range of pixels in the gray level image from 0 to 50, from 51 and over 101, and we estimated each range as daytime, evening and night. In the first step, it is estimated based on the intensity and chromaticity of the image. If the classification result based on the intensity and chromaticity image is the same, the process is terminated. Otherwise, the k-means segmentation is used in the second step to determine the final classification. Some experiments are conducted so as to verify the proposed method, and the classification is well performed. The execution time results up to the first step are about 0.31 seconds on average, and the execution up to the second step is changed according to the resolution of the image.
关键词： daytime and night,k-means segmentation,intensity,classification,chromaticity
更新于2025-09-19 17:15:36
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Low Intensity Light-Induced Paclitaxel Release from Lipid Based Nano-delivery Systems
摘要： Light-induced drug release has been explored as a strategy for externally modulating the release of drug from delivery systems. This study reports the development of a solid lipid nanoparticulate system (SLN) for paclitaxel (PTX), where photosensitizer-mediated oxidation of lipids was used as a mechanism for controlling the drug release. Low-intensity (23 mW/cm2) near-infrared (around 730 nm) illumination was externally applied as the light source. Paclitaxel release was less than 10% within 4 hrs from these SLN and was 8-fold higher after application of light at time zero. The other advantages of this approach include the use of ascorbic acid as an antioxidant for enhancing the release and storage stability of the delivery system. Antioxidant like ascorbic acid in the SLN decrease the degradation of lipid by 8-fold within 4 months of storage. Presence of ascorbic acid and light illumination of SLN containing PTX further decreased the IC50 by 2 times in A549 cells. The uniqueness of this approach allows the possibility of external modulation to achieve pulsatile release from the delivery system. The light used in the NIR spectral range of 700-850 nm, which has the greatest tissue penetration ability, with a low intensity will be safe for normal tissues.
关键词： near-infrared photosensitizer,anticancer,lipid nanoparticles,hydrophobic drugs,controlled release,low-intensity light
更新于2025-09-19 17:15:36
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Reducing the surface recombination during light-driven water oxidation by core-shell BiVO4@Ni:FeOOH
摘要： The photocurrent of BiVO4 is limited by surface recombination not surface catalysis, which is currently reported as the main restrict factor for high efficiency photo-electrochemical (PEC) water splitting. To solve this problem, an ultrathin Ni:FeOOH (~ 8 nm) modified nanoporous BiVO4 photoanode (BiVO4@Ni:FeOOH) was constructed with core-shell structure for PEC water oxidation. Attributed to the p-n hetero-junction formed between BiVO4 and Ni:FeOOH, the photocurrent density of BiVO4@Ni:FeOOH increased by a factor of 11 (2.86 mA cm-2 at 1.23 V vs. RHE), together with ~ 180 mV negative shift of onset potential under AM 1.5 G irradiation (100 mW cm-2) in comparison to the pristine BiVO4. More importantly, detailed insight into the fate of the photo-generated charge carriers at the surface is investigated. Intensity modulated photocurrent spectroscopy (IMPS) is used to investigate the surface carrier dynamics of BiVO4 and BiVO4@Ni:FeOOH. IMPS results and hole scavenger measurement (HSM) certify the main role of Ni:FeOOH is to improve surface recombination by largely decreasing the surface recombination rate constant (krec), not surface catalysis. This work demonstrates Ni:FeOOH can facilitate local surface kinetics and reduce recombination rates as well and be used in other photoelectrodes especially the photoanodes with surface defects for PEC water splitting.
关键词： Core-shell,intensity modulated photocurrent spectroscopy,p-n heterojunction,surface recombination
更新于2025-09-19 17:15:36
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Recurrent neural networks for discrimination of exo-atmospheric targets based on infrared radiation signature
摘要： Exo-atmospheric infrared (IR) target discrimination is an important research problem in space attack and defense. The different micro-motion states of the targets result in respective characteristics in the obtained IR radiation intensity sequences, and this difference is difficult to describe intuitively and extract effectively. Few methods can effectively contact the data with the micro-motion model, resulting in a low classification accuracy and difficult to meeting actual application requirements. We set up four types of targets by constructing the micro-motion model of the exo-atmospheric targets, including the warhead and heavy decoy, with spinning and coning motion; and the light decoy and debris, with tumbling motion, to get the IR radiation intensity sequences. We use random projection to improve the discrimination power of recurrent neural network, and to classify the time series of IR radiation intensity. Experimental results demonstrate that random projection recurrent neural network (R-RNN) is more effective than several other typical algorithms in time series classification (TSC) task, which can achieve an excellent target discrimination. We also analyze the effect of noise on the performance of the algorithm.
关键词： Recurrent neural network,Exo-atmospheric target discrimination,Micro-motion model,IR radiation intensity,Random projection
更新于2025-09-19 17:15:36
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An optical multiple-image authentication based on transport of intensity equation
摘要： An optical multiple-image authentication approach based on transport of intensity equation technique has been proposed. Initially, a phase-encoded plaintext is synthesized with significant blocks chosen from the multiple plain images by evaluating their spatial frequency coefficients, which is bonded with a random intensity mask generated with logistic map to constitute the complex amplitude. Then, the complex amplitude is encrypted to a real-valued ciphertext with noise-like distribution by using Fresnel diffraction. In the process of authentication, the phase information is firstly reconstructed by solving transport of intensity equation. The existence of a plain image can be identified by calculating the nonlinear correlation between it and its partial data only containing the extracted significant blocks from the phase information by aid of the corresponding binary mask. To our best knowledge, it is the first time to apply the transport of intensity equation technique to implement the optical multiple-image authentication. A set of numerical simulations are carried out to demonstrate the feasibility of the proposed approach.
关键词： Transport of intensity equation,Multiple-image authentication,Spatial frequency coefficient
更新于2025-09-19 17:15:36
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A Decision Support Tool For Early Detection of Knee OsteoArthritis using X-ray Imaging and Machine Learning: Data from the OsteoArthritis Initiative
摘要： This paper presents a fully developed computer aided diagnosis (CAD) system for early knee OsteoArthritis (OA) detection using knee X-ray imaging and machine learning algorithms. The X-ray images are first preprocessed in the Fourier domain using a circular Fourier filter. Then, a novel normalization method based on predictive modeling using multivariate linear regression (MLR) is applied to the data in order to reduce the variability between OA and healthy subjects. At the feature selection/extraction stage, independent component analysis (ICA) is used in order to reduce the dimensionality. Finally, Naive Bayes and random forest classifiers are used for the classification task. This novel image-based approach is applied on 1024 knee X-ray images from the public database OsteoArthritis Initiative (OAI). The results show that the proposed system has a good predictive classification rate for OA detection (82.98 % for accuracy, 87.15 % for sensitivity and up to 80.65 % for specificity).
关键词： Computer Aided diagnosis System,Intensity Normalization,Classification,OsteoArthritis
更新于2025-09-19 17:15:36
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Analytic and simulative comparison of turbulent FSO system with different modulation techniques
摘要： In this paper, we characterize the performance of Intensity Modulation/Direct Detection (IM/DD) and coherent detection modulation techniques in free-space optical (FSO) communication system in terms of bit error rate (BER). The system of interest includes M-ary Pulse Position Modulation (M-PPM) in correspondence to IM/DD and M-ary Phase Shift Keying (M-PSK) and M-ary Quadrature Amplitude Modulation (M-QAM) with respect to coherent detection. The system is subjected to weak turbulence regime of log-normal channel with scintillation index less than 0.75. Coherent techniques involve the amount of signal pulses transmitted in a particular time as the major component of their generation, except IM/DD which is a result of photon intensity, i.e. the number of photons forming a pulse. It is worth mentioning that in previous studies, the performance of IM/DD techniques had been evaluated in terms of photon-count fluctuation statistics and thus the impact of fading strength of channel on signal intensity was not discussed anywhere. In this work, an objective equivalence has been achieved between these two kinds of detection by deriving the BER expression of M-PPM in terms of probability density function of signal intensity, while considering fading strength, scintillation index, thermal noise and outage probability as system parameters for numerical analysis.
关键词： M-ary Pulse Position Modulation (MPPM),M-ary Phase Shift Keying (MPSK),M-ary Quadrature Amplitude Modulation (M-QAM),Intensity Modulation/Direct Detection (IM/DD),Scintillation index,Coherent detection
更新于2025-09-19 17:15:36
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Envelope Detection of 16QAM Single Carrier Signal for IM/DD RoF System at Q-band
摘要： In this paper, an envelope detection scheme of single carrier 16-ary Intensity-Modulation/Direct-Detection (IM/DD) radio-over-fiber (RoF) system is theoretically and experimentally investigated. Based on the proposed scheme, the mm-wave 16QAM signal is down-converted to the intermediate frequency (IF) 16QAM one by an envelope detector (ED) and there is no use of a mixer at the user side. We theoretically and experimentally study the performance of the signal under various conditions. In the system, 2GBaud 16QAM signal is delivered over 25km standard single mode fiber (SSMF) link and 2.9m wireless link under bit error rate (BER) of 3.8×10-3.
关键词： Radio-over-fiber (RoF),Intensity-Modulation/Direct-Detection (IM/DD),Envelope detection
更新于2025-09-19 17:15:36