Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "sensing" wg kryterium: Wszystkie pola

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 22
Tytuł:
Image compression-encryption algorithm combining compressive sensing with log operation
Autorzy:
Chen, R.-L.
Zhou, Y.
Luo, M.
Zhang, A.-D.
Gong, L.-H.
Powiązania:
https://bibliotekanauki.pl/articles/174009.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
image encryption
image compression
compressive sensing
log operation
Opis:
Based on compressive sensing and log operation, a new image compression-encryption algorithm is proposed, which accomplishes encryption and compression simultaneously. The proposed image compression-encryption algorithm takes advantage of not only the physical realizability of partial Hadamard matrix, but also the resistance of the chosen-plaintext attack since all the elements in the partial Hadamard matrix are 1, –1 or log 1 = 0. The proposed algorithm is sensitive to the key and it can resist various common attacks. The simulation results verify the validity and reliability of the proposed image compression-encryption algorithm.
Źródło:
Optica Applicata; 2018, 48, 4; 563-573
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Image compression and encryption algorithm with wavelet-transform-based 2D compressive sensing
Autorzy:
Fan, Jing-Hui
Liu, Xian-Bao
Chen, Yan-Bin
Powiązania:
https://bibliotekanauki.pl/articles/175122.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
wavelet transform
compressive sensing
chaos scrambling
image encryption
image compression
Opis:
By combining a wavelet transform with chaos scrambling, an image compression and encryption algorithm based on 2D compressive sensing is designed. The wavelet transform is employed to obtain the sparse representation of a plaintext image. The sparse image is measured in two orthogonal directions by compressive sensing. Then, the result of 2D compressive sensing is confused by the Arnold transform and the random pixel scrambling. The combination of four-dimensional chaos and logistic map is exploited to generate the first row of the key-controlled circulant matrix. The proposed algorithm not only carries out image compression and encryption simultaneously, but also reduces the consumption of the key by controlling the generation of measurement matrix. Experimental results reveal that the proposed image compression and encryption algorithm is resistant to noise attacks with good compression performance and high key sensitivity.
Źródło:
Optica Applicata; 2019, 49, 3; 461-472
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
In-fiber Mach–Zehnder interferometer based on polarization-maintaining fiber for displacement and temperature sensing
Autorzy:
Cheng, Jun-Ni
Jiang, Xiao-Yan
Powiązania:
https://bibliotekanauki.pl/articles/2202764.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
displacement sensing
polarization-maintaining fiber
graded-index multimode fiber
Mach-Zehnder interferometer
Opis:
A displacement sensor based on polarization-maintaining fiber has been proposed and proved in experiment. The polarization-maintaining fiber (PMF) is sandwiched with two graded-index multimode fibers (GI MMF), which form the Mach–Zehnder interferometer (MZI) sensor. Graded-index multimode fiber serve as an optical coupler for modes conversion. The results show that with the increase of displacement, the spectrum moves to the long wavelength direction, but when temperature increases, the spectrum has a red shift, which means that the displacement and temperature can be measured separately according to the wavelength drift direction. The sensor consists of 4 mm GI MMF and 14 mm PMF, which can exhibit the displacement sensitivity of –9.275 pm/μm in the range of 0–600 μm. In addition, temperature will also affect the sensitivity of displacement measurement, so the sensitivity of the sensor to temperature is also measured. The results show that the selected monitoring dip provides a better temperature sensitivity of 33.605 pm/°C in the range of 35–75°C. The sensor is easy to fabricate and does not has any functional coating, which make it become a good candidate in the industrial field.
Źródło:
Optica Applicata; 2023, 53, 1; 21--33
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compressive-sensing-based double-image encryption algorithm combining double random phase encoding with Josephus traversing operation
Autorzy:
Jiang, Hao
Nie, Zhe
Zhou, Nanrun
Zhang, Wenquan
Powiązania:
https://bibliotekanauki.pl/articles/173461.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
image encryption
compressive sensing
double random phase encoding
Josephus traversing
Opis:
A double-image encryption scheme based on compressive sensing is designed by combining a double random phase encoding technique with Josephus traversing operation. Two original images are first compressed and encrypted by compressive sensing in the discrete wavelet domain and then connected into a complex image according to the order of the alternate rows. Moreover, the resulting image is re-encrypted into stationary white noise by a double random phase encoding technique. Lastly, Josephus traversing method is utilized to scramble the transformed image. The initial states of the Henon chaotic map are the secret keys of this double-image encryption algorithm, which can be used to control the construction of the measurement matrix in compressive sensing and generation of the random-phase mask in double random phase encoding. Simulation results show that the proposed double-image encryption algorithm is effective and secure.
Źródło:
Optica Applicata; 2019, 49, 3; 445-459
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Colloidal crystal cladded microfiber for refractive index sensing
Autorzy:
Yan, H. T.
Zhao, X Y
Zhang, Ch.
Zhen, Z Q
Li, Q Z
Cao, J X
Xia, L X
Powiązania:
https://bibliotekanauki.pl/articles/174902.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
microfibers
colloidal crystals
refractive index sensing
Opis:
We investigate the evanescent field of a microfiber wrapped by colloidal crystals. The microfiber has the diameter of about 1 μm that is drawn from a single-mode fiber with an alcohol lamp. The colloidal spheres are further attached to the microfiber through thermal evaporation, then they self-assemble to crystal-like structures. The 400 nm, 590 nm, and 710 nm-diameter SiO2 colloidal spheres are used, respectively. The spectral responses are studied theoretically and experimentally, and the results agree with each other. It is revealed that the evanescent field of a microfiber could be modulated by the photonic band-gap of colloidal crystals. This characteristic is very useful in refractive index sensing for liquids.
Źródło:
Optica Applicata; 2014, 44, 2; 309-315
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Color image encryption scheme based on quaternion discrete multi-fractional random transform and compressive sensing
Autorzy:
Ye, Huo-Sheng
Dai, Jing-Yi
Wen, Shun-Xi
Gong, Li-Hua
Zhang, Wen-Quan
Powiązania:
https://bibliotekanauki.pl/articles/2033985.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
color image encryption
quaternion discrete multi-fractional random transform
compressive sensing
confusion-diffusion strategy
Opis:
A color image compression-encryption algorithm by combining quaternion discrete multi-fractional random transform with compressive sensing is investigated, in which the chaos-based fractional orders greatly improve key sensitivity. The original color image is compressed and encrypted with the assistance of compressive sensing, in which the partial Hadamard matrix adopted as a measurement matrix is constructed by iterating Chebyshev map instead of utilizing the entire Guassian matrix as a key. The sparse images are divided into 12 sub-images and then represented as three quaternion signals, which are modulated by the quaternion discrete multi-fractional random transform. The image blocking and the quaternion representation make the proposed cryptosystem avoid additional data extension existing in many transform-based methods. To further improve the level of security, the plaintext-related key streams generated by the 2D logistic-sine-coupling map are adopted to diffuse and confuse the intermediate results simultaneously. Consequently, the final ciphertext image is attained. Simulation results reveal that the proposed cryptosystem is feasible with high security and has strong robustness against various attacks.
Źródło:
Optica Applicata; 2021, 51, 3; 349-364
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical investigation of slab waveguide sensor using anisotropic metamaterial
Autorzy:
Taya, S. A.
Powiązania:
https://bibliotekanauki.pl/articles/174457.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
anisotropic waveguides
optical sensing
double negative materials
Opis:
A three-layer slab waveguide with air as a substrate, lossless dielectric as a guiding film, and anisotropic double negative material as a cladding is explored as an optical sensor for refractometry applications. The double negative material is assumed to have a negative electric permittivity and magnetic permeability only along the wave propagation direction. The sensitivity of a guided mode to the variation in the refractive index of air substrate is derived and studied for the first few guided modes. It is found that the sensitivity can be enhanced with decreasing the guided light frequency as well as the film thickness. The sensitivity can reach 100% for some waveguide configurations.
Źródło:
Optica Applicata; 2015, 45, 3; 405-417
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Monitoring and identification of marine oil spills using advanced synthetic aperture radar images
Autorzy:
Mihoub, Z
Hassini, A.
Powiązania:
https://bibliotekanauki.pl/articles/173181.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sea pollution
remote sensing
oil spills detection
ENVISAT-ASAR images
Opis:
The aim of this study is to propose and test a new methodology for detection of oil spills in the world oceans from advanced synthetic aperture radar imagery embedded in ENVISAT satellite (ENVISAT-ASAR). The proposed and applied methodology includes four levels: data acquisition, dark spots detection, features extraction and dark spots classification for discrimination between oil spills and look-alikes. Level 1 contains the ENVISAT-ASAR wide swath mode data acquisition. Level 2 begins with a visual interpretation based on experience and a priori information concerning location, external information about weather conditions, differences in shape, and contrast to surroundings between oil spills and look-alikes, then filtering and segmentation. Level 3 contains extraction of features from the detected dark spots. Level 4 aim is to discriminate oil spills from look-alikes using the features extracted by means of object-based fuzzy classification. As a result, oil slicks are discriminated from look-alikes with an overall accuracy classification of 91% for oil slicks and 86% for look-alikes. Finally, to validate our results, the method has been tested by comparing the areas of the automatically detected oil spills (object-based fuzzy classification) with the areas of the manually detected oil spills (region of interest), by means of area ratios.
Źródło:
Optica Applicata; 2014, 44, 3; 433-449
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of palladium chemical structure on hydrogen sensing properties of carbonaceous–palladium thin films
Autorzy:
Kaminska, A.
Krawczyk, S.
Kozlowski, C.
Powiązania:
https://bibliotekanauki.pl/articles/173783.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
C–Pd thin films
hydrogen sensor
FTIR spectroscopy
Opis:
In this work we investigate nanocomposite carbonaceous–palladium (C–Pd) films prepared by physical vapor deposition. Such films are promising materials for hydrogen sensor applications. This is related to the highly selective hydrogen absorption by palladium nanocrystallites. The C–Pd films obtained in various technological conditions differ in structure and electrical properties. These films were characterized by SEM, EDS and FTIR spectroscopy. FTIR spec-troscopy was used to determine the amount of palladium acetate and fullerene, incompletely decomposed during the deposition process. FTIR spectra enabled us to explain the differences in C–Pd films resistance based on palladium chemical structure. The possibility of the application of C–Pd films as active layers in hydrogen sensors was also studied. The results showed that synthesized C–Pd films containing palladium nanograins could be used for hydrogen sensing.
Źródło:
Optica Applicata; 2013, 43, 4; 633-640
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ammonia level sensor using tapered optical fiber coated with titanium dioxide-incorporated porphyrin
Autorzy:
Parasuti, Frazna
Hikmawati, Dyah
Trilaksana, Herri
Yasin, Moh.
Powiązania:
https://bibliotekanauki.pl/articles/27310105.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ammonia sensing
tapered optical fibre
titanium dioxide
porphyrin
Opis:
Since ammonia is water-soluble, environmental studies have shown that the industrial waste such as fertilizer manufacturing, food products, palm oil, urea fertilizer industry can cause very serious damage to water body ecosystems if not properly managed, resulting in a decrease in water quality. Devices based on optical technology, especially devices that combine optical fibers and nanomaterials, are identified as highly sensitive to the species of interest by detecting changes in physicochemical properties. A practical, easy-to-use, inexpensive instrument for detecting ammonia level was proposed using tapered optical fiber (TOF) coated with titanium dioxide-incorporated porphyrin. TOF was fabricated by simultaneously stretching and heating. The preparation of TiO2/porphyrin/gelatine was prepared to coat tapered optical fiber by dipping. SEM analysis shows an increase in length and a decrease in diameter, also the successful coating of titanium dioxide and porphyrin in the taper region. The EDX analysis also proves the presence of the Ti element in the TOF layer. The TOF produces significant sensing performances toward the ammonia liquid concentration level. The TOF coated with titanium dioxide-incorporated porphyrin can detect a one ppm difference in ammonia concentration with a certain range of output voltage for every concentration has.
Źródło:
Optica Applicata; 2023, 53, 3; 353--361
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microarray-core based circular photonic crystal fiber for high chemical sensing capacity with low confinement loss
Autorzy:
Asaduzzaman, S.
Ahmed, K.
Powiązania:
https://bibliotekanauki.pl/articles/174575.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
circular photonic crystal fiber
confinement loss
elliptical core
chemical sensor
relative sensitivity
Opis:
In this article, a circular photonic crystal fiber based chemical sensor has been presented where core region is designed with an array of elliptical holes. The proposed structure is numerically investigated by using a full vectorial finite element method. From the numerical results, it is observed that introducing an array of elliptical holes helps to obtain the high relative sensitivity and realizes a low confinement loss. In addition, the increase in the value of the diameter of holes in the innermost ring enhances the relative sensitivity. Moreover, the increase in the value of the diameter of holes in the outermost ring reduces the confinement loss. In this work, we have considered an industrially valuable chemical ethanol. Simulation results disclose that the highest relative sensitivity of proposed photonic crystal fiber is 29.25% for ethanol and the confinement loss is 7.68 × 10–7 dB/m at the wavelength 1.5 µm.
Źródło:
Optica Applicata; 2017, 47, 1; 41-49
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nanoslotted microring resonator for high figure of merit refractive index sensing
Autorzy:
Yang, Daquan
Duan, Bing
Zhang, Xuan
Lu, Hui
Powiązania:
https://bibliotekanauki.pl/articles/174324.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
nanoslot
microring resonator
refractive index sensor
figure of merit
integrated nanophotonics
3D-FDTD
Opis:
A nanoslotted microring resonator (NSMR) with enhanced light-matter interaction has been designed, which can be used for high sensitive refractive index sensing. The performance of the device is investigated theoretically based on a three-dimensional finite-difference time-domain (3D-FDTD) method. In order to achieve high figure of merit sensing, the nanoslot geometry is exploited to make the optical field strongly localized inside the low index region and overlap sufficiently with the analytes. By using the 3D-FDTD method, the proposed NSMR sensor device achieves a high Q-factor (Q > 105) and sensitivity ~100 nm/RIU (RIU – refractive index unit). Moreover, the strong light confinement introduced by the nanoslot in NSMR results in the sensor figure of merit as high as 6.73 × 103. Thus, the design we proposed is a promising platform for refractive index-based biochemical sensing and lab-on-a-chip applications.
Źródło:
Optica Applicata; 2020, 50, 1; 37-47
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Single air-mode resonance photonic crystal nanofiber cavity for ultra-high sensitivity refractive index sensing
Autorzy:
Zhang, Yanni
Yang, Jiaxi
Song, Meiqi
Zhang, Xuan
Yang, Daquan
Powiązania:
https://bibliotekanauki.pl/articles/173916.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
photonic crystal nanocavity
air mode nanofiber
refractive index sensor
sensitivity
Opis:
We propose a design of series-connected one-dimensional photonic crystal nanofiber cavity sensor (1-D PC-NCS) and one-dimensional photonic crystal nanofiber bandgap filter (1-D PC-NBF). The proposed structure can get a single air mode for refractive index sensing with its extinction ratio of 58.64 dB. It filters out the high order mode and reduces the interaction between signals. By 3D FDTD, the calculated sensitivity is 848.18 nm/RIU (RIU – refractive index unit). Compared with general silicon on-chip nanobeam cavity, the sensitivity is increased by eight times. The additional 1-D PC-NBF will not change the sensitivity and the position of the resonance wavelength. Therefore, the new design we propose addresses the issue of crosstalk, and can be applied to ultra-high sensitivity index-based gas sensing and biosensing without the need for complicated coupling systems.
Źródło:
Optica Applicata; 2020, 50, 2; 199-207
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of soft-sensing model for ash content prediction of flotation tailings by image features tailings based on GA-SVMR
Autorzy:
Wang, Guanghui
He, Ting
Kuang, Yali
Lin, Zhe
Powiązania:
https://bibliotekanauki.pl/articles/1449310.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
GA-SVMR
image features
flotation
ash content
Opis:
Ash content is one of the most important properties of coal quality and the ash prediction of coal slurry in floatation is urgent and important for automation of the floatation process. The aim of this paper is to propose a method of ash content prediction for flotation tailings by the use of image analysis. The mean gray value, energy, skewness and coal slurry concentration are highly correlated with coal slurry ash content by correlation analysis based on experiments while the particles’ size has little effect on the ash. Single variable linear prediction model between coal ash content and mean gray value was developed by the LS and its prediction errors were below 7%. For improving the prediction results, an ash prediction model based on GA-SVMR was established with additional three input parameters: energy, skewness, coal slurry concentration. This model has a higher accuracy with predictive errors all below 5% and 80% of them less than 3%. Results indicate that GA-SVMR model has a higher precision compared with LS model and PSO-SVMR model and soft-sensing model based on image features of the slurry can be used as a new method for ash detection of floatation tailings in automatic control process of coal flotation.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 4; 590-598
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compressed optical image encryption in the diffractive-imaging-based scheme by input plane and output plane random sampling
Autorzy:
Wan, Shujia
Gong, Qiong
Wang, Hongjuan
Ma, Shibang
Qin, Yi
Powiązania:
https://bibliotekanauki.pl/articles/2060687.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
diffractive-imaging-based encryption
compressive sensing
random sampling
Opis:
The successful recovery of the plaintext in the simplified diffractive-imaging-based encryption (S-DIBE) scheme needs to record one intact axial intensity map as the ciphertext. By aid of compressive sensing, we propose here a new image encryption approach, referred to as compressed DIBE (C-DIBE), which allows further compression of the intensity map. The plaintext is sampled before being sent to DIBE. Afterwards, the intensity map recorded by the CCD camera is also processed by such sampling operation to generate the ciphertext. For decryption, we first obtain the sparse plaintext using the proposed phase retrieval algorithm, and then reobtain the primary plaintext from it via compressive sensing. Numerical results show that a proper proportion of the intensity map (e.g. 50%) is enough to totally recover a grayscale image. We achieve multiple-image encryption by space multiplexing without enlarging the size of the ciphertext. The robustness of C-DIBE against brute-force attack evidently outperforms S-DIBE due to the extended key space. Numerical simulation has been presented to confirm the proposal.
Źródło:
Optica Applicata; 2022, 52, 1; 51--66
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 22

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies