Autor: Chen, A. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Finite-difference time-domain solution of second-order photoacoustic wave equation
Autorzy:: Rahimzadeh, A.
Chen, S.-L.
Powiązania:: https://bibliotekanauki.pl/articles/173969.pdf
Data publikacji:: 2016
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: photoacoustic tomography
numerical simulation
finite-difference time-domain
second-order photoacoustic equation
Opis:: A finite-difference time-domain numerical solution is presented for solving a single second-order photoacoustic equation, instead of solving three coupled first-order equations. In this way, we are able to insert the heating function to the simulation directly instead of initial pressure. Results are validated using k-Wave simulation and show a good agreement for future development. The perfectly matched layer boundary condition has been implemented for a second-order photoacoustic equation and results are compared to Dirichlet, Neumann and Mur boundary conditions.
Źródło:: Optica Applicata; 2016, 46, 3; 435-446
0078-5466
1899-7015
Pojawia się w:: Optica Applicata
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Improved Roberts focusing evaluation method for an autofocusing system
Autorzy:: Yin, A.
Dai, Z.
Chen, B.
Li, K.
Powiązania:: https://bibliotekanauki.pl/articles/173381.pdf
Data publikacji:: 2013
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: focus evaluation function
evaluation window
autofocusing
Opis:: In this paper, a new focusing evaluation method based on local 2/8 center windows is proposed for an autofocusing system. We have proposed an evaluation function which improved the Roberts function with eight-neighborhood or four-neighborhood. The approximate optimal criteria window is selected by a 2/8 rule. Comparative experiments implemented with other methods have shown that the 2/8 rule method not only can find the approximate optimal evaluation window quickly, but also has better generality. This evaluation function of improved Roberts’ function has higher sensitivity and better real-time performance.
Źródło:: Optica Applicata; 2013, 43, 3; 529-538
0078-5466
1899-7015
Pojawia się w:: Optica Applicata
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

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

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