An Improved Fast Camera Calibration Method for Mobile Terminals

Guan, Fang-li,Xu, Ai-jun,Jiang, Guang-yu Korea Information Processing Society 2019 Journal of information processing systems Vol.15 No.5

Camera calibration is an important part of machine vision and close-range photogrammetry. Since current calibration methods fail to obtain ideal internal and external camera parameters with limited computing resources on mobile terminals efficiently, this paper proposes an improved fast camera calibration method for mobile terminals. Based on traditional camera calibration method, the new method introduces two-order radial distortion and tangential distortion models to establish the camera model with nonlinear distortion items. Meanwhile, the nonlinear least square L-M algorithm is used to optimize parameters iteration, the new method can quickly obtain high-precise internal and external camera parameters. The experimental results show that the new method improves the efficiency and precision of camera calibration. Terminals simulation experiment on PC indicates that the time consuming of parameter iteration reduced from 0.220 seconds to 0.063 seconds (0.234 seconds on mobile terminals) and the average reprojection error reduced from 0.25 pixel to 0.15 pixel. Therefore, the new method is an ideal mobile terminals camera calibration method which can expand the application range of 3D reconstruction and close-range photogrammetry technology on mobile terminals.

An Improved Fast Camera Calibration Method for Mobile Terminals

Fang-li Guan,Ai-jun Xu,Guang-yu Jiang 한국정보처리학회 2019 Journal of information processing systems Vol.15 No.5

Camera calibration is an important part of machine vision and close-range photogrammetry. Since currentcalibration methods fail to obtain ideal internal and external camera parameters with limited computingresources on mobile terminals efficiently, this paper proposes an improved fast camera calibration method formobile terminals. Based on traditional camera calibration method, the new method introduces two-order radialdistortion and tangential distortion models to establish the camera model with nonlinear distortion items. Meanwhile, the nonlinear least square L-M algorithm is used to optimize parameters iteration, the new methodcan quickly obtain high-precise internal and external camera parameters. The experimental results show thatthe new method improves the efficiency and precision of camera calibration. Terminals simulation experimenton PC indicates that the time consuming of parameter iteration reduced from 0.220 seconds to 0.063 seconds(0.234 seconds on mobile terminals) and the average reprojection error reduced from 0.25 pixel to 0.15 pixel. Therefore, the new method is an ideal mobile terminals camera calibration method which can expand theapplication range of 3D reconstruction and close-range photogrammetry technology on mobile terminals.

부모의 학대가 청소년의 또래애착에 미치는 영향: 자아존중감과 공격성의 매개효과

장관방 ( Guan Fang Zhang ),김영미 ( Young Mi Kim ) 동의대학교 지방자치연구소 2014 공공정책연구 Vol.31 No.2

청소년이 가장 중요한 지지체계인 부모로부터 일상적으로 경험하는 학대적 양육은 이들의 사회. 정서적 발달에 심각한 영향을 미친다. 이에 본 연구는 청소년들의 부모 피학대 경험이 또래애착에 미치는 영향을 파악하고, 이 과정에서 공격성과 자 아존중감의 매개효과를 검증하고자 했다. 본 연구는 부모애착이론과 사회학습이론 의 검토와 선행연구 결과를 토대로 연구문제를 설정한 후, 한국아동청소년 패널조 사(KCYPS)의 중학교 1학년 3차년도 자료 2,259사례를 활용하여 분석했다. 연구문제 는 위계적 회귀분석을 통해 Baron과 Kenny(1986)의 4단계 분석으로 검증했고, 매 개효과의 유의성은 Sobel 검증을 통해 확인했다. 분석결과를 보면, 첫째, 부모의 학 대는 청소년의 또래애착에 직접적인 영향을 미쳤으며, 부모의 학대수준이 높을수록 청소년들이 또래애착수준이 낮았다. 둘째, 부모의 학대는 청소년의 자아존중감의 매개과정을 통해 또래애착에 간접적 영향을 미쳤으며, 이 과정에서 자아존중감은 유의미한 부분매개효과를 보였다. 셋째, 부모의 학대는 공격성의 매개과정을 통해 서도 또래애착에 영향을 미쳤으며, 공격성 또한 이 과정에서 유의미한 부분매개효 과를 나타냈다. 마지막으로, 가구소득이 높을수록 부모의 학대와 청소년의 공격성 수준은 낮은 반면, 또래애착과 자아존중감 정도는 높은 것으로 확인되었다. Since parents are a crucial support system for adolescents, parental child abuse has significant influences on social and emotional development ofadolescents. Thus, the purpose of this study was to examine the influence of parental child abuse on adolescent peer attachment. Additionally, this study focused on the mediating effects of self-esteem and aggression between parental child abuse and adolescent peer attachment. A total of 2,259 adolescent data from third wave of Korean Child and Youth Panel Study was used in this study. Research questions were examined through the mediator analysis method of Baron and Kenny using hierarchical regression analysis. The study also performed Sobel test to identify the statistical significance of mediators. The main findings are as follows. First, parental child abuse had a direct influence on adolescent peer attachment. That is, higher levels of parental child abuse were related to lower levels of peer attachment. Second, parental child abuse affected indirectly adolescent peer attachment through partial mediating effects of self-esteem. Third, parental child abuse also had indirect influence on adolescent peer attachment through partial mediating effects of aggression. In particular, the results showed that mediating effects of self-esteem and aggressin were statistically significant. Fourth, annual family income affected inversely parental child abuse and aggression. However, the results indicated the higher level of family income was relatedto the higher degree of adolescent peer attachment and self-esteem. This study suggests some implications for practical intervention on the levels of school setting and community family agency.

The work effectiveness and its influencing factors of child directors in China

Guan Qiujie,Zhang Shu,Zhao Fang 한국사회복지학회 2024 Asian Social Work and Policy Review Vol.18 No.1

Implementing the child director policy is an innovation in China's child protection practice, and the work of child directors aims to provide care and protection services for vulnerable children in communities and villages. According to the person–environment fit theory (i.e., needs–supplies fit), this study evaluated the work effectiveness of child directors and its influencing factors from environmental and personal perspectives. The results revealed that the supportive work environment (i.e., management, training, and supervision) and personal factors (i.e., professional competency and career identity) positively influenced the work effectiveness of child directors, and professional competency and career identity mediated the relationship between the supportive work environment and the work effectiveness. The findings provided evidence for improving the implementation of child director policy in the future.

Preparation and Thermal Performance of Fullerene-Based Lead Salt

Guan, Hui-Juan,Peng, Ru-Fang,Jin, Bo,Liang, Hua,Zhao, Feng-Qi,Bu, Xing-Bing,Han, Wen-Jing,Chu, Shi-Jin Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.8

$C_{60}$ is widely investigated because of its unique structure. But its applications in solid propellant seem to be relatively neglected. $C_{60}$ has more outstanding features than carbon black which is widely used as a catalyst ingredient of solid propellant. To combine the advantages of fullerene and lead salts, another good composite in propellant catalysts, we synthesized a kind of fullerene phenylalanine lead salt (FPL) and explored its thermal performances by differential thermal analysis (DTA) and thermogravimetry analysis (TGA). The results show it undergoes four exothermic processes started from 408 K. Combined TGA and X-ray diffractometer (XRD), the decomposition mechanism of FPL was derived by TG-IR and comparing IR spectra of FPL and its residues after burned to $327^{\circ}C$, $376^{\circ}C$ and $424^{\circ}C$, respectively. Effect of FPL on the decomposition characteristic of hexogen (RDX), a type of explosive in propellant, has been investigated using DTA at different heating rate, which shows the decomposition temperatures of the explosive are all reduced by more than 20 K. The corresponding activation energy ($E_a$) is decreased by $30kJ{\cdot}mol^{-1}$. So FPL has potential application as a combustion catalyst in solid propellant.

The promoter of fatty acid desaturase on chromosome C5 in Brassica napus drives high-level expression in seeds

Fang Liu,Guiluan Wang,Ruiyang Liu,Chunyun Guan 한국식물생명공학회 2016 Plant biotechnology reports Vol.10 No.6

The gene fatty acid desaturase 2 (FAD2) exists in multiple copies in the Brassica napus genome and encodes an enzyme that catalyzes the conversion of oleic acid to linoleic acid. In the present study, we characterized the regulatory region controlling the expression of an FAD2 gene located on chromosome C5 of Brassica napus and named it BnFAD2-C5. A long intron was found within the 50-untranslated region (50-UTR) of the BnFAD2-C5 gene. This intron, compared with an intron-less control, conferred up to a sixfold increase in green fluorescent protein (GFP) expression in transgenic Arabidopsis, thus suggesting that it makes function through intron-mediated enhancement. The sequence containing the promoter and intron was identified to promote high levels of gene expression in genital organs, particularly in seeds, using qRT-PCR and transgenic Arabidopsis. We identified the different promoter regions responsible for the tissuespecific gene expression through a deletion analysis of the BnFAD2-C5 promoter and a b-glucuronidase and GFP reporter system. The results showed that the -1020 to -319 bp region primarily controls BnFAD2-C5 gene expression in the root, whereas the -1020 to -581 bp region controls expression in the stem, the -581 to -319 bp region controls expression in the leaf, and the -1257 to -1020 bp region probably controls expression in the floral parts. The -319 to -1 bp region is also important, conferring high-level transcription in the seeds. The transcription of BnFAD2-C5 could be induced by salicylic acid and jasmonic acid, and the relative response elements were identified in the -1257 to -1020 bp region and -319 to -1 bp region, respectively.

Diversity Analysis of Burkholderia cepacia Complex in the Water Bodies of West Lake, Hangzhou, China

Yuan Fang,Guan-lin Xie,Miao-miao Lou,Bin Li,Ibrahim Muhammad 한국미생물학회 2011 The journal of microbiology Vol.49 No.2

A survey of Burkholderia cepacia complex (Bcc) species was conducted in water bodies of West Lake in China. A total of 670 bacterial isolates were recovered on selective media. Out of them, 39.6% (265 isolates)were assigned to the following species: Burkholderia multivorans, Burkholderia cenocepacia recA lineage IIIA,IIIB, Burkholderia stabilis, Burkholderia vietnamiensis, and Burkholderia seminalis while B. cenocepacia is documented as a dominant Bcc species in water of West Lake. In addition, all Bcc isolates tested were PCR negative for the cblA and esmR transmissibility marker genes except B. cenocepacia IIIB A8 which was positive for esmR genelater. The present study raises great concerns on the role of West Lake as a “reservoir” for potential Bcc pathogenic strains.

Reports ; Adrenergic receptor β2 activation by stress promotes breast cancer progression through macrophages M2 polarization in tumor microenvironment

( Jun-fang Qin ),( Feng-jiao Jin ),( Ning Li ),( Hai-tao Guan ),( Lan Lan ),( Hong Ni ),( Yue Wang ) 생화학분자생물학회 2015 BMB Reports Vol.48 No.5

Stress and its related hormones epinephrine (E) and norepinephrine (NE) play a crucial role in tumor progression. Macrophages in the tumor microenvironment (TME) polarized to M2 is also a vital pathway for tumor deterioration. Here, we explore the underlying role of macrophages in the effect of stress and E promoting breast cancer growth. It was found that the weight and volume of tumor in tumor bearing mice were increased, and dramatically accompanied with the rising E level after chronic stress using social isolation. What is most noteworthy, the number of M2 macrophages inside tumor was up-regulated with it. The effects of E treatment appear to be directly related to the change of M2 phenotype is reproduced in vitro. Moreover, E receptor ADRβ2 involved in E promoting M2 polarization was comprehended simultaneously. Our results imply psychological stress is influential on specific immune system, more essential for the comprehensive treatment against tumors. [BMB Reports 2015; 48(5): 295-300]

Characterizing the strain transfer on the sensing cable-soil interface based on triaxial testing

Dan Zhang,Guan-Zhong Wu,Tai-Song Shan,Bin Shi,Yuan-Jiang Fang,Kang Ren 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.30 No.1

The deformation coordination between a rock/soil mass and an optical sensing cable is an important issue for accurate deformation monitoring. A stress-controlled triaxial apparatus was retrofitted by introducing an optical fiber into the soil specimen. High spatial resolution optical frequency domain reflectometry (OFDR) was used for monitoring the strain distribution along the axial direction of the specimen. The results were compared with those measured by a displacement meter. The strain measured by the optical sensing cable has a good linear relationship with the strain calculated by the displacement meter for different confining pressures, which indicates that distributed optical fiber sensing technology is feasible for soil deformation monitoring. The performance of deformation coordination between the sensing cable and the soil during unloading is higher than that during loading based on the strain transfer coefficients. Three hypothetical strain distributions of the triaxial specimen are proposed, based on which theoretical models of the strain transfer coefficients are established. It appears that the parabolic distribution of specimen strain should be more reasonable by comparison. Nevertheless, the strain transfer coefficients obtained by the theoretical models are higher than the measured coefficients. On this basis, a strain transfer model considering slippage at the interface of the sensing cable and the soil is discussed.

The subcellular distribution of MnSOD alters during sodium selenite-induced apoptosis

( Li Ying Guan ),( Qi An Jiang ),( Zhu Shi Li ),( Fang Huang ),( Yun Ren ),( Yang Yang ),( Cai Min Xu ) 생화학분자생물학회 2009 BMB Reports Vol.42 No.6