2011
2011
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Record 73 of
Title:Robust sparse tensor decomposition by probabilistic latent semantic analysis
Author(s):Pang, Yanwei(1); Ma, Zhao(1); Pan, Jing(2); Yuan, Yuan(3)Source: Proceedings - 6th International Conference on Image and Graphics, ICIG 2011 Volume: Issue: DOI: 10.1109/ICIG.2011.98 Published: 2011Abstract:Movie recommendation system is becoming more and more popular in recent years. As a result, it is becoming increasingly important to develop machine learning algorithm on partially-observed matrix to predict users' preferences on missing data. Motivated by the user ratings prediction problem, we propose a novel robust tensor probabilistic latent semantic analysis (RT-pLSA) algorithm that not only takes time variable into account, but also uses the periodic property of data in time attribute. Different from the previous algorithms of predicting missing values on two-dimensional sparse matrix, we formulize the prediction problem as a probabilistic tensor factorization problem with periodicity constraint on time coordinate. Furthermore, we apply the Tsallis divergence error measure in the context of RT-pLSA tensor decomposition that is able to robustly predict the latent variable in the presence of noise. Our experimental results on two benchmark movie rating dataset: Netflix and Movielens, show a good predictive accuracy of the model. ? 2011 IEEE.Accession Number: 20113914362074 -
Record 74 of
Title:Integrating kAS and SIFT-like descriptor for image description
Author(s):Shang, Mianyou(1); Pan, Jing(2); Pang, Yanwei(1); Yuan, Yuan(3)Source: Proceedings - 6th International Conference on Image and Graphics, ICIG 2011 Volume: Issue: DOI: 10.1109/ICIG.2011.164 Published: 2011Abstract:Shape-descriptor (e.g. Adjacent Contour Segments, i.e. kAS) and keypoint-descriptor (e.g. Scale Invariant Feature Transform, i.e. SIFT) are widely used for computer vision. However, few works principally integrate shape-descriptor and keypoint-descriptor to describe the content of an image. On one hand, in some cases the degree of locality of keypiont-descriptor is too high to capture semantic characteristics of an object. On the other hand, though the shape has higher semantic level than keypoint, it contains no texture information because only the information of contour/edge is used. To make full use of the information of both shape and keypoint for generate robust and distinctive features, in this paper we propose an algorithm to integrate shape and keypoint descriptor. Specifically, we employ kAS to extract useful shape information. Then keypoints of a kAS shape are defined at which we propose to extract SIFT-like features. Experimental results on image matching demonstrate the effectiveness of the proposed algorithm. ? 2011 IEEE.Accession Number: 20113914361990 -
Record 75 of
Title:A low power adaptive clock and data recovery circuit for wireless implantable systems
Author(s):Yu, Hang(1); Li, Yan(1); Jiang, Lai(1); Ji, Zhen(1); Yan, Ping-Kun(2); Wang, Fei(3)Source: Shenzhen Daxue Xuebao (Ligong Ban)/Journal of Shenzhen University Science and Engineering Volume: 28 Issue: 2 DOI: Published: March 2011Abstract:An extremely low power clock and data recovery circuit was designed for pulse position modulated input. Synchronized clock and data were recovered through converting the timing distance between pulses into voltage domain. The reference voltage required for data recovery was adaptively generated to extend the range of the input data rate. The design was validated using 0.25 μm CMOS technology. With 45.5 kbits/s input data, the entire circuit only consumes less than 13 μW of power.Accession Number: 20111913972248 -
Record 76 of
Title:A novel LED lens for rotationally symmetric uniform illumination
Author(s):Yan, Xingtao(1,2); Yang, Jianfeng(1); Bu, Fan(1,2); Zhang, Guoqi(3)Source: ICEOE 2011 - 2011 International Conference on Electronics and Optoelectronics, Proceedings Volume: 3 Issue: DOI: 10.1109/ICEOE.2011.6013306 Published: 2011Abstract:Traditional LED (light emitting diode) packaging always adopts hemisphere lens, and can ensure high light output efficiency, but its radiation pattern yields Lambert distribution and is non-uniformity. To enable LED light sources be applied in uniform illumination system, a method to obtain freeform LED lens based on energy equipartition and tangent iteration is proposed. Firstly, according to the Lambertian distribution of LED light intensity and its rotationally symmetric peculiarity, the LED emission angle is divided into N parts in Two-dimensional coordinate system, and the energy contained in each part is equal; Secondly, the target plane is divided into N equal areas along its radii, and the discrete points are corresponding to the N parts of emission angle. So that if the energy in each divided solid angle is controlled to illuminate the equal divided area, the illumination of each corresponding micro-belt on the target plane will be uniform; Finally, to avoid the total reflection of large emission angle rays, the designed lens will refract the rays with 0～450 emission angle and reflect the rays with 450～900 emission angle. Choosing an initial point on the freeform generatrix, and using Snell equation and tangent iteration method, the coordinates of all points on the freeform generatrix are obtained, which could be rotated into the freeform surface of the lens. The simulation results using the designed LED lens show that for a rotationally symmetric target plane the illumination uniformity is near to 90% and the energy efficiency is higher than 95%. ? 2011 IEEE.Accession Number: 20114014386421 -
Record 77 of
Title:Accurate measuring temperature with infrared thermal imager in the unstable condition of ambient temperature
Author(s):Wang, Jing(1); Qu, En-Shi(1); Cao, Jian-Zhong(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8201 Issue: DOI: 10.1117/12.906280 Published: 2011Abstract:The infrared thermal imaging systems are widely used for distinguishing target radiation temperature difference and they can also be used to measure the absolute temperature of the target. There may be great difference between the true value and the measurement results in the actual application of the infrared thermal imaging systems, just because of the unstable condition and the lack of compensation of the imager's own heat radiation. In order to obtain the accurate temperature of the target in some special conditions, such as aircraft internal and pilotless platform, we present a stationary infrared thermal imaging system to gather the goal gradation images and a method to compensate the influence of the imager's own heat radiation and the unstable condition. In radiation calibration experiment, we establish corresponding relationships between the gradation difference and the temperature difference by using a goal blackbody and a cooperation calibration blackbody between 0°C and 150°C. We also analysis the relationships mentioned above under the normal temperature and the high temperature separately. The results show that the proposed method may be useful in increasing the temperature measurement precision. ? 2011 SPIE.Accession Number: 20120314693189 -
Record 78 of
Title:Two bore-sight stereo mapping with single lens, TDI CCD pushing model imaging and compensations of the speed-to-height rate - Chang'e-2 CCD camera
Author(s):Zhao, Baochang(1); Wen, Desheng(1); Yang, Jianfeng(1); Gao, Wei(1); Chang, Lingying(1); Xue, Bin(1); Song, Zongxi(1)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 31 Issue: 9 DOI: 10.3788/AOS201131.0900115 Published: September 2011Abstract:The synthetic technical option of two bore-sight stereo mapping with single lens, the time delayed and integration (TDI) CCD pushing model imaging and the compensations technique of the speed-to-height rate of Chang'e-2 satellite TDI CCD stereo camera is proposed. It is the first time to employ two TDI CCD as imaging sensors and obtain clear image with high spatial resolution. In order to keep the synchronism between the optical image motion speed on the focal plane array (FPA) and the electronic latent image motion speed during pushing imaging with TDI CCD camera, two speed-to-height rates compensation methods are used: line frequency injection from the ground station and laser altimeter aided line frequency calculation. The camera's mean modulation transfer function is bigger than 0.4 which is tested before the launch. Because of the optimal design, careful fabrication and precise installation, accuracy requirement of on-orbit speed-to-height rate compensation is relaxed. Because technical measures are synthetically used in TDI CCD camera, clear stereo images of the global lunar surface with resolution of 7 m, the highest spatial resolution global images, and the clear images of Sinus Iridum with about 1.3 m resolution on the near-moon-arc of the 15 km × 100 km ellipsoid orbit are both obtained. The capability of obtaining high spatial resolution stereo imaging of lunar surface is achieved.Accession Number: 20114914584067 -
Record 79 of
Title:InAs/GaSb type-II superlattice grown by MOCVD for long-wavelength infrared detection
Author(s):Xin, Liwei(1,3); Wang, Tao(1); Yang, Jin(1,3); Wang, Jingwei(1,3); Yin, Fei(1); Hu, Yanan(1); Jiao, Guohua(1,3); Zhang, Lichen(1,3); Yin, Jingzhi(2); Song, Zhenyu(2)Source: Optoelectronics and Advanced Materials, Rapid Communications Volume: 5 Issue: 9 DOI: Published: September 2011Abstract:Recently, many characteristics of the InAs/GaSb type-II superlattice(SL) have been investigated. However, little research work has been devoted to the source flux control, which is very important for improving the property of the SL. Based on the technology of metal organic chemical vapor deposition (MOCVD) on GaSb substrate, which has a better cost effectiveness for large-scale production, SL with excellent crystal quality is proposed in this paper. Furthermore, the importance of source flux control is analyzed by comparison of the low-temperature photoluminescence (PL) spectra of the SL grown with a special source flux control and that with a simple source flux control. The x-ray diffraction(XRD) data and the surface morphology obtained by atomic force microscopy(AFM) show that the SL designed by us has smooth surface, and the peak sense wavelength of the SL is around 10 μm.Accession Number: 20203409075139 -
Record 80 of
Title:Die bonding of single emitter semiconductor laser with nano-scale silver paste
Author(s):Yan, Yi(1); Chen, Xu(1); Liu, XingSheng(2,3); Lu, Guo-Quan(4,5)Source: ICEPT-HDP 2011 Proceedings - 2011 International Conference on Electronic Packaging Technology and High Density Packaging Volume: Issue: DOI: 10.1109/ICEPT.2011.6067029 Published: 2011Abstract:One of the most important steps in the manufacturing of laser diodes is bonding the chip onto some sort of sub-mount that allows the laser to be handled, durable electrical connections to be made, and heat to be conducted away from the laser itself. The ability to conduct heat away from the laser is critical in keeping operating temperatures low, thus improving the laser's performance and its lifetime. In this study, it's the first time to use nano-scale silver paste as a die-attach material for die bonding the laser diodes. Numerous tests have been carried out to check the silver paste packaged laser's performance, including electrical properties, spectral properties, far-field characteristics, thermal rollover characteristics and so on. The test results show that as a new interconnecting material, nano-silver paste has the potential to eliminate the deficiencies of the existing solders. ? 2011 IEEE.Accession Number: 20114714540036 -
Record 81 of
Title:A new adaptive background correction method based on pinhole image analysis in optical system modulation transfer function measurement
Author(s):Duan, Yaxuan(1); Chen, Yongquan(1); Zhao, Jianke(1); Li, Kun(1); Long, Jiangbo(1)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 31 Issue: 8 DOI: 10.3788/AOS201131.0812008 Published: August 2011Abstract:A new adaptive background correction method based on pinhole image analysis in optical system modulation transfer function (MTF) measurement is proposed. The pinhole image is got from the CCD, and the line spread function is computed from it. The MTF is got from the adaptive background correction to the line spread function. Compared with the traditional background correction method, it is unrelated to the change of ambience illumination, and the measurement accuracy is improved. Standard lens and aberrated lens are tested to prove the validity of the adaptive background method. The maximum difference between the test results of standard lens and the academic results is 0.01. Compared with Optikos MTF testing results, the maximum difference is 0.015. The maximum difference between test results of aberrated lens and Optikos MTF testing results is 0.013. The test results show that the adaptive background correction method is practical to the MTF tests of most optical lenses.Accession Number: 20113714332403 -
Record 82 of
Title:3-Dimensional thermal analysis of Yb3+-doped gain guided and index-antiguided fiber amplifier
Author(s):Kun-Lun, Yan(1,2); En-Yu, Zhou(4); Wei, Wei(1,3); Bo, Peng(1,4)Source: Optics Communications Volume: 284 Issue: 6 DOI: 10.1016/j.optcom.2010.11.033 Published: March 15, 2011Abstract:In this paper, the thermal characteristics of gain-guided and index-antiguided (GG-IAG) fiber amplifier were investigated with a 3-D heat flow model, based on rate equations. From the simulation results, it is found that the longitudinal heat conduction has a very important influence on the GG-IAG fiber amplifier temperature distribution, and the GG-IAG fiber amplifier would be subjected to a more serious thermal problem. Finally, the influence of different pump directions, cooling methods, cladding radius and negative refractive index step on the temperature distribution has also been studied. ? 2010 Elsevier B.V. All rights reserved.Accession Number: 20110613655165 -
Record 83 of
Title:Broadband near-infrared emission in Tm3+-Dy3+ codoped amorphous chalcohalide films fabricated by pulsed laser deposition
Author(s):Yang, Senlin(1); Wang, Xuefeng(1); Guo, Haitao(2); Dong, Guoping(3); Peng, Bo(2); Qiu, Jianrong(3); Zhang, Rong(1); Shi, Yi(1)Source: Optics Express Volume: 19 Issue: 27 DOI: 10.1364/OE.19.026529 Published: December 19, 2011Abstract:Structural and near-infrared (NIR) emission properties were investigated in the Tm3+-Dy3+ codoped Ge-Ga-based amorphous chalcohalide films fabricated by pulsed laser deposition. The homogeneous films illustrated similar random network to the glass target according to the measurements of X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. An 808 nm laser diode pumping generated a superbroadband NIR emission ranging from 1050 to 1570 nm and the other intense broadband NIR emission centered at ～1800 nm, which was attributed to the efficient energy transfer from Tm 3+ to Dy3+ ions. This was further verified by the broad-range excitation measurements near the Urbach optical-absorption edge involved defect states. The results shed light on the potential highly integrated planar optical device applications of the codoped amorphous chalcohalide films. ? 2011 Optical Society of America.Accession Number: 20120114657572 -
Record 84 of
Title:Adaptively learning local shape statistics for prostate segmentation in ultrasound
Author(s):Yan, Pingkun(1); Xu, Sheng(2); Turkbey, Baris(3); Kruecker, Jochen(2)Source: IEEE Transactions on Biomedical Engineering Volume: 58 Issue: 3 PART 1 DOI: 10.1109/TBME.2010.2094195 Published: March 2011Abstract:Automatic segmentation of the prostate from 2-D transrectal ultrasound (TRUS) is a highly desired tool in many clinical applications. However, it is a very challenging task, especially for segmenting the base and apex of the prostate due to the large shape variations in those areas compared to the midgland, which leads many existing segmentation methods to fail. To address the problem, this paper presents a novel TRUS video segmentation algorithm using both global population-based and patient-specific local shape statistics as shape constraint. By adaptively learning shape statistics in a local neighborhood during the segmentation process, the algorithm can effectively capture the patient-specific shape statistics and quickly adapt to the local shape changes in the base and apex areas. The learned shape statistics is then used as the shape constraint in a deformable model for TRUS video segmentation. The proposed method can robustly segment the entire gland of the prostate with significantly improved performance in the base and apex regions, compared to other previously reported methods. Our method was evaluated using 19 video sequences obtained from different patients and the average mean absolute distance error was 1.65 ± 0.47 mm. ? 2006 IEEE.Accession Number: 20111013715348