Visual Quality Enhancement of Three-Dimensional Integral Imaging Reconstruction for Partially Occluded Objects Using Exemplar-Based Image Restoration

Zhang, Miao,Zhong, Zhaolong,Piao, Yongri The Korea Institute of Information and Commucation 2016 Journal of information and communication convergen Vol.14 No.1

In generally, the resolution of reconstructed three-dimensional images can be seriously degraded by undesired occlusions in the integral imaging system, because the undesired information of the occlusion overlap the three-dimensional images to be reconstructed. To solve the problem of the undesired occlusion, we present an exemplar-based image restoration method in integral imaging system. In the proposed method, a minimum spanning tree-based stereo matching method is used to remove the region of undesired occlusions in each elemental image. After that, the removed occlusion region of each elemental images are re-established by using the exemplar-based image restoration method. For further improve the performance of the image restoration, the structure tensor is used to solve the filling error cause by discontinuous structures. Finally, the resolution enhanced three-dimensional images are reconstructed by using the restored elemental images. The preliminary experiments are presented to demonstrate the feasibility of the proposed method.

Visibility-enhanced reconstruction of three-dimensional objects under a heavily scattering medium through combined use of intermediate view reconstruction, multipixel extraction, and histogram equalization methods in the conventional integral imaging sys

Zhang, Miao,Piao, Yongri,Kim, Eun-Soo The Optical Society 2011 Applied optics Vol.50 No.28

<P>In this paper, we propose an effective approach for reconstructing visibility-enhanced three-dimensional (3D) objects under the heavily scattering medium of dense fog in the conventional integral imaging system through the combined use of the intermediate view reconstruction (IVR), multipixel extraction (MPE), and histogram equalization (HE) methods. In the proposed system, the limited number of elemental images (EIs) picked up from the 3D objects under the dense fog is increased by as many as required by using the IVR technique. The increased number of EIs is transformed into the subimages (SIs) in which the resolution of the transformed SIs has been also improved as much as possible with the MPE method. Subsequently, by using the HE algorithm, the histogram of the resolution-enhanced SIs is uniformly redistributed over the entire range of discrete pixel levels of the image in a way that the subimage contrast can be much enhanced. Then, these equalized SIs are converted back into the newly modified EIs, and consequently a visibility-enhanced 3D object image can be reconstructed. Successful experimental results with the test object confirmed the feasibility of the proposed method.</P>

Occlusion-removed scheme using depth-reversed method in computational integral imaging

Zhang, Miao,Piao, Yongri,Kim, Eun-Soo The Optical Society 2010 Applied Optics Vol.49 No.14

Hsp70 and HSF-1 expression is altered in the tissues of pigs transported for various periods of times

Miao Zhang,Zhenhua Yue,Zhijun Liu,Ali Islam,Buriro Rehana,Shu Tang,Jörg Hartung,Endong Bao 대한수의학회 2012 JOURNAL OF VETERINARY SCIENCE Vol.13 No.3

The aim of this study was to assess changes of Hsp70 and HSF-1 protein and mRNA expression in stress-sensitive organs of pigs during transportation for various periods of time. Twenty pigs were randomly divided into four groups (0 h, 1 h, 2 h, and 4 h of transportation). A significant increased activity of AST and CK was observed after 1 h and 2 h of transportation. Histopathological changes in the heart, liver, and stomach indicated that these organs sustained different degrees of injury. Hsp70 protein expression in the heart and liver of transported pigs did not change significantly while it increased significantly (p < 0.05) in the stomach. Hsp70 mRNA levels decreased significantly (p < 0.05) in the heart after 4 h of transportation. However, mRNA expression increased significantly in the liver after 1 (p < 0.05) and 4 h (p < 0.01) of transportation, and increased significantly in the stomach of the transported pigs after 1, 4 (p < 0.01), and 2 h (p < 0.05). HSF-1 levels were reduced at 1 and 4 h (p < 0.05) only in the hearts of transported pigs. These results indicate that Hsp70 mediates distinct stress-related functions in different tissues during transportation.

Continuous Conduction Mode Soft-Switching Boost Converter and its Application in Power Factor Correction

Miao-miao Cheng,Zhiguo Liu,Yueyue Bao,Zhongjie Zhang 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

Continuous conduction mode (CCM) boost converters are commonly used in home appliances and various industries because of their simple topology and low input current ripples. However, these converters suffer from several disadvantages, such as hard switching of the active switch and reverse recovery problems of the output diode. These disadvantages increase voltage stresses across the switch and output diode and thus contribute to switching losses and electromagnetic interference. A new topology is presented in this work to improve the switching characteristics of CCM boost converters. Zero-current turn-on and zero-voltage turn-off are achieved for the active switches. The reverse-recovery current is reduced by soft turning-off the output diode. In addition, an input current sensorless control is applied to the proposed topology by pre-calculating the duty cycles of the active switches. Power factor correction is thus achieved with less effort than that required in the traditional method. Simulation and experimental results verify the soft-switching characteristics of the proposed topology and the effectiveness of the proposed input current sensorless control.

커브 형 집적영상에서 직접 픽셀매핑을 이용한 먼 거리 3D 물체의 해상도 개선

Miao Zhang,Yongri Piao,김은수 한국통신학회 2010 한국통신학회 학술대회논문집 Vol.2010 No.2

Industrialization in an Age of China Rising: A Tale of Two Chinese Automobile Companies in Malaysia

Miao Zhang,Guanie Lim 경남대학교 극동문제연구소 2023 ASIAN PERSPECTIVE Vol.47 No.4

This article aims to contribute to the exploration of the ways through which Malaysia.the fourth largest economy in Southeast Asia.has engaged Chinese investment to pursue industrialization. It does so by comparing and contrasting the different approaches by which two of the most important Chinese-financed automobile projects, Chery Automobile’s assembly operations in 2008 and Zhejiang Geely’s partial acquisition of local producer Proton in 2017, have been embedded into the Malaysian political economy. While Chery Automobile ended up with a conundrum of extremely low local sales, Zhejiang Geely has fostered mutually beneficial partnerships with Proton and its cohort of suppliers that are shaped by the industry’s ethnopolitical directives. More recently, Zhejiang Geely has exported an increasingly larger proportion of vehicles from its Malaysian operations. The contrasting fate of these projects illustrates that while they are driven by Chinese money and technological know-how, they are not necessarily Chinese-dominated. It is domestic politics.the establishment of a functional politico-commercial coalition in particular.that matters in shaping the outcome and impact of Chinese investment in Malaysia. More importantly, the paper highlights how foreign direct investment and the supposed (positive and negative) externalities are intimately tied to local factors such as political institutions and ethnocentric directives.

Distortion-free wide-angle 3D imaging and visualization using off-axially distributed image sensing.

Zhang, Miao,Piao, Yongri,Kim, Nam-Woo,Kim, Eun-Soo Optical Society of America 2014 Optics letters Vol.39 No.14

<P>We propose a new off-axially distributed image sensing (ODIS) using a wide-angle lens for reconstructing distortion-free wide-angle slice images computationally. In the proposed system, the wide-angle image sensor captures a wide-angle 3D scene, and thus the collected information of the 3D objects is severely distorted. To correct this distortion, we introduce a new correction process involving a wide-angle lens to the computational reconstruction in ODIS. This enables us to reconstruct distortion-free, wide-angle slice images for visualization of 3D objects. Experimental results are carried out to verify the proposed method. To the best of our knowledge, this is the first time the use of a wide-angle lens in a multiple-perspective 3D imaging system is described.</P>

A Method of Reference Point Range for Field Navigation of Agricultural Robot

Zhang Miao 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.2

The measurement value of the traditional binocular parallax distance is the distance between the reference point P and the center of the baseline of the binocular camera, and for the agriculture robot, because of the needs of ground operations, the cameras are usually installed in certain height from the ground with a certain angle with the horizontal direction, when we have to know the horizontal distance from the navigation reference point to the robot body and thus the next travel pose of the robot can be controlled by real-time. Obviously, the traditional binocular parallax distance measuring methods will no longer apply to this. In this regard, a new method for solving agricultural robot navigation reference point distance measurement is proposed. First, conduct calibration for the binocular system with the improved BP neural network, and secondly, obtain the left and right image coordinates of the navigation reference point (U1,V1) (U2,V2) with the improved SIFT features and input the BP neural networks trained in the calibration, and finally, output the coordinates of the navigation reference point in the world coordinate system (X,Y), and then the horizontal distance between the navigation reference point and the robot body can be expressed as S = X2 + Y2 . Experiments show that by this method, the maximum deviation of the actual field experiment test is 0.479cm, with the minimum deviation of 0.032cm, accuracy up to 99%, consuming a total of 55ms. And compared to the traditional binocular parallax distance ranging procedure, the computation is significantly reduced, with certain engineering practicability and feasibility.

Limited Unilateral Decompression and Pedicle Screw Fixation with Fusion for Lumbar Spinal Stenosis with Unilateral Radiculopathy : A Retrospective Analysis of 25 Cases

Zhang, Li,Miao, Hai-xiong,Wang, Yong,Chen, An-fu,Zhang, Tao,Liu, Xiao-guang The Korean Neurosurgical Society 2015 Journal of Korean neurosurgical society Vol.46 No.4

Objective : Lumbar spinal stenosis is conventionally treated with surgical decompression. However, bilateral decompression and laminectomy is more invasive and may not be necessary for lumbar stenosis patients with unilateral radiculopathy. We aimed to report the outcomes of unilateral laminectomy and bilateral pedicle screw fixation with fusion for patients with lumbar spinal stenosis and unilateral radiculopathy. Methods : Patients with lumbar spinal stenosis with unilateral lower extremity radiculopathy who received limited unilateral decompression and bilateral pedicle screw fixation were included and evaluated using visual analog scale (VAS) pain and the Oswestry Disability Index (ODI) scores preoperatively and at follow-up visits. Ligamentum flavum thickness of the involved segments was measured on axial magnetic resonance images. Results : Twenty-five patients were included. The mean preoperative VAS score was $6.6{\pm}1.6$ and $4.6{\pm}3.1$ for leg and back pain, respectively. Ligamentum flavum thickness was comparable between the symptomatic and asymptomatic side (p=0.554). The mean follow-up duration was 29.2 months. The pain in the symptomatic side lower extremity (VAS score, $1.32{\pm}1.2$) and the back (VAS score, $1.75{\pm}1.73$) significantly improved (p=0.000 vs. baseline for both). The ODI improved significantly postoperatively ($6.60{\pm}6.5$; p=0.000 vs. baseline). Significant improvement in VAS pain and ODI scores were observed in patients receiving single or multi-segment decompression fusion with fixation (p<0.01). Conclusion : Limited laminectomy and unilateral spinal decompression followed by bilateral pedicle screw fixation with fusion achieves satisfactory outcomes in patients with spinal stenosis and unilateral radiculopathy. This procedure is less damaging to structures that are important for maintaining posterior stability of the spine.