We constructed a flexible gold-polydimethylsiloxane(gold-PDMS)nanocomposites film with controllable thickness and light transmittance,to realize optically-excited simultaneous photo-acoustic(PA)and ultrasound(US)imagi...We constructed a flexible gold-polydimethylsiloxane(gold-PDMS)nanocomposites film with controllable thickness and light transmittance,to realize optically-excited simultaneous photo-acoustic(PA)and ultrasound(US)imaging under a single laser pulse irradiation.Benefiting from the excellent thermoelastic properties,the gold-PDMS film absorbs part of the incident laser energy and produces a high-intensity US,which is used to realize US imaging.Meanwhile,the partly transmitted light is used to excite samples for PA imaging.By controlling the thickness of the gold-PDMS,we can control the center frequency in the US imaging.We experimentally analyzed the frequency of the produced US signal by the gold-PDMSfilm and compared it with the finite element analysis(FEA)method,where the experiments agree with the FEA results.This method is demonstrated by the experiments on phantoms and a mouse model.Our work provides a cost-effective methodology for simultaneous PA and US imaging.展开更多
Aiming at the reference range selection for different antennas in interferometric inverse synthetic aperture radar （InlSAR） systems, this paper proposes a respective focusing （RF） method. The reference ranges for ...Aiming at the reference range selection for different antennas in interferometric inverse synthetic aperture radar （InlSAR） systems, this paper proposes a respective focusing （RF） method. The reference ranges for echoes of different antennas are selected respectively for RF, which is different from the traditional uniform focusing （UF） with the same reference range applied to all the antennas. First, a comparison between UF and RF for InlSAR signal model considering the ranging error is given. Compared with RF, UF has an advantage in overcoming the ranging error differences between different antennas. Then the influence of ranging error upon the interferometric imaging with RF is investigated particularly, and it is found that the ranging error differences between different antennas are far smaller than the wavelength, which is advantageous to imaging. By comparing the capabilities of inter- ferometric imaging between RF and UF, it is concluded that RF is a better choice in conquering problems such as image mismatching and phase ambiguity even with ranging errors. Simulations demonstrate the validity of the proposed method.展开更多
This paper proposes a model for image restoration by combining the wavelet shrinkage and inverse scale space （ISS） method. The ISS is applied to the wavelet representation to modify the retained wavelet coefficients...This paper proposes a model for image restoration by combining the wavelet shrinkage and inverse scale space （ISS） method. The ISS is applied to the wavelet representation to modify the retained wavelet coefficients, and the coefficients smaller than the threshold are set to zero. The curvature term of the ISS can remove the edge artifacts and preserve sharp edges. For the multiscale interpretation of the ISS and the multiscale property of the wavelet representation, small details are preserved. This paper illustrates that the wavelet ISS model can be deduced from the wavelet based on a total variation minimization problem. A stopping criterion is obtained from this minimization in the sense of the Bregman distance in the wavelet domain. Numerical examples show the improvement for the image denoising with the proposed method in the sense of the signal to noise ratio and with fewer details remained in the residue.展开更多
As a powerful tool for image processing,bi-dimensional empirical mode decomposition (BEMD) covers a wide range of applications. In this paper,we explore a novel hyperspectral classification algorithm which integrates ...As a powerful tool for image processing,bi-dimensional empirical mode decomposition (BEMD) covers a wide range of applications. In this paper,we explore a novel hyperspectral classification algorithm which integrates BEMD and support vector machine (SVM) . By virtue of BEMD,the selected hyperspectral bands are decomposed into several bi-dimensional intrinsic mode functions (BIMFs) ,which reflect the essential properties of hyperspectral image. We further make full use of SVM,which is a supervised classification tool widely accepted,to classify the suitable sum of BIMFs. Experimental results indicate that though the proposed method has no advantage in computing time,it exhibits higher classification accuracy and stability than the classical SVM.展开更多
The temperature and magnetic moment depend-ence for assessing localized heating utilizing a new class of Manganese-Zinc-Gadolinium mag-netic nanoparticles was studied. These particles showed heating effect when subjec...The temperature and magnetic moment depend-ence for assessing localized heating utilizing a new class of Manganese-Zinc-Gadolinium mag-netic nanoparticles was studied. These particles showed heating effect when subjected to alter-nating filed. Alternatively, a new approach was used to get disperse heating without spot heating by using the synthesis of particles at controlled Curie temperature of less than 44oC. The study reports a simple synthesis of Mn0.5Zn0.5GdxFe(2-x)O4 nanoparticles using chemical co- precipita-tion technique. The particles exhibited Curie temperature of 42篊 and high magnitude of mag-netic moments. The particles showed sigmoid behavior of dependence between temperature and magnetic moments. The Nuclear Magnetic Resonance spectroscopy showed T1 depend-ence on temperature in the range of 10-45篊. The particles may have high promise for self con-trolled magnetic hyperthermia application and its monitoring.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(61805085)The Natural Science Foundation of Guangdong Province(2018A030310519)+1 种基金The Young innovative talents project of general colleges and universities in Guangdong ProvinceThe Guangzhou Science and technology plan project(201904010321)
文摘We constructed a flexible gold-polydimethylsiloxane(gold-PDMS)nanocomposites film with controllable thickness and light transmittance,to realize optically-excited simultaneous photo-acoustic(PA)and ultrasound(US)imaging under a single laser pulse irradiation.Benefiting from the excellent thermoelastic properties,the gold-PDMS film absorbs part of the incident laser energy and produces a high-intensity US,which is used to realize US imaging.Meanwhile,the partly transmitted light is used to excite samples for PA imaging.By controlling the thickness of the gold-PDMS,we can control the center frequency in the US imaging.We experimentally analyzed the frequency of the produced US signal by the gold-PDMSfilm and compared it with the finite element analysis(FEA)method,where the experiments agree with the FEA results.This method is demonstrated by the experiments on phantoms and a mouse model.Our work provides a cost-effective methodology for simultaneous PA and US imaging.
基金supported by the National Science Fund for Distinguished Young (61025006)the National Science Foundation for Young Scientists of China (61101182)
文摘Aiming at the reference range selection for different antennas in interferometric inverse synthetic aperture radar （InlSAR） systems, this paper proposes a respective focusing （RF） method. The reference ranges for echoes of different antennas are selected respectively for RF, which is different from the traditional uniform focusing （UF） with the same reference range applied to all the antennas. First, a comparison between UF and RF for InlSAR signal model considering the ranging error is given. Compared with RF, UF has an advantage in overcoming the ranging error differences between different antennas. Then the influence of ranging error upon the interferometric imaging with RF is investigated particularly, and it is found that the ranging error differences between different antennas are far smaller than the wavelength, which is advantageous to imaging. By comparing the capabilities of inter- ferometric imaging between RF and UF, it is concluded that RF is a better choice in conquering problems such as image mismatching and phase ambiguity even with ranging errors. Simulations demonstrate the validity of the proposed method.
基金supported by the National Natural Science Foundation of China (61101208)
文摘This paper proposes a model for image restoration by combining the wavelet shrinkage and inverse scale space （ISS） method. The ISS is applied to the wavelet representation to modify the retained wavelet coefficients, and the coefficients smaller than the threshold are set to zero. The curvature term of the ISS can remove the edge artifacts and preserve sharp edges. For the multiscale interpretation of the ISS and the multiscale property of the wavelet representation, small details are preserved. This paper illustrates that the wavelet ISS model can be deduced from the wavelet based on a total variation minimization problem. A stopping criterion is obtained from this minimization in the sense of the Bregman distance in the wavelet domain. Numerical examples show the improvement for the image denoising with the proposed method in the sense of the signal to noise ratio and with fewer details remained in the residue.
基金Sponsored by the National Natural Science Foundations of China (Grant No.60975009 and 61171197)Research Fund for the Doctoral Program of Higher Education of China (Grant No.20092302110037 and 20102302110033)
文摘As a powerful tool for image processing,bi-dimensional empirical mode decomposition (BEMD) covers a wide range of applications. In this paper,we explore a novel hyperspectral classification algorithm which integrates BEMD and support vector machine (SVM) . By virtue of BEMD,the selected hyperspectral bands are decomposed into several bi-dimensional intrinsic mode functions (BIMFs) ,which reflect the essential properties of hyperspectral image. We further make full use of SVM,which is a supervised classification tool widely accepted,to classify the suitable sum of BIMFs. Experimental results indicate that though the proposed method has no advantage in computing time,it exhibits higher classification accuracy and stability than the classical SVM.
文摘The temperature and magnetic moment depend-ence for assessing localized heating utilizing a new class of Manganese-Zinc-Gadolinium mag-netic nanoparticles was studied. These particles showed heating effect when subjected to alter-nating filed. Alternatively, a new approach was used to get disperse heating without spot heating by using the synthesis of particles at controlled Curie temperature of less than 44oC. The study reports a simple synthesis of Mn0.5Zn0.5GdxFe(2-x)O4 nanoparticles using chemical co- precipita-tion technique. The particles exhibited Curie temperature of 42篊 and high magnitude of mag-netic moments. The particles showed sigmoid behavior of dependence between temperature and magnetic moments. The Nuclear Magnetic Resonance spectroscopy showed T1 depend-ence on temperature in the range of 10-45篊. The particles may have high promise for self con-trolled magnetic hyperthermia application and its monitoring.
