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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:42
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow SPINDLE FANCY YAM spinning machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 multi - bar WARP KNITTED fabric computer -aided PATTERN design PATTERN Object Windows class Library (OWL) programming.
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MODS: A Novel Metaheuristic of Deterministic Swapping for the Multi-Objective Optimization of Combinatorials Problems
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作者 Elias David Nifio Ruiz Carlos Julio Ardila Hemandez +2 位作者 Daladier Jabba Molinares Agustin Barrios Sarmiento Yezid Donoso Meisel 《Computer Technology and Application》 2011年第4期280-292,共13页
This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Auto... This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Automata (MDFA) is defined. MDFA allows the representation of the feasible solutions space of combinatorial problems. Second, it is defined and implemented a metaheuritic based on MDFA theory. It is named Metaheuristic of Deterministic Swapping (MODS). MODS is a local search strategy that works using a MDFA. Due to this, MODS never take into account unfeasible solutions. Hence, it is not necessary to verify the problem constraints for a new solution found. Lastly, MODS is tested using well know instances of the Bi-Objective Traveling Salesman Problem (TSP) from TSPLIB. Its results were compared with eight Ant Colony inspired algorithms and two Genetic algorithms taken from the specialized literature. The comparison was made using metrics such as Spacing, Generational Distance, Inverse Generational Distance and No-Dominated Generation Vectors. In every case, the MODS results on the metrics were always better and in some of those cases, the superiority was 100%. 展开更多
关键词 METAHEURISTIC deterministic finite automata combinatorial problem multi - objective optimization metrics.
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ARC-FSK中程多载波水声通信新技术 被引量:2
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作者 于同泉 韦周芳 程彬彬 《计算机仿真》 CSCD 2006年第11期308-310,345,346,共5页
海洋水声信道是一种极其复杂多变的时-空-频变参信道。信道通带窄、多途干扰强、衰落严重足水声通信高速可靠传输信息的主要障碍。该文针对中程(10~30km)多载波水声通信系统提出一种非对称升余弦频移键控调制(ARC—FSK)信号。该信... 海洋水声信道是一种极其复杂多变的时-空-频变参信道。信道通带窄、多途干扰强、衰落严重足水声通信高速可靠传输信息的主要障碍。该文针对中程(10~30km)多载波水声通信系统提出一种非对称升余弦频移键控调制(ARC—FSK)信号。该信号在频率调制的基础上,结合了非对称信号的稳健抗多途特性与相位调制(CPM)信号的高频谱效率,实现了最佳系统性能。理论分析及仿真结果表明:该ARC—FSK信号多释抑制有效,性能稳健,更适合于恶劣水声信道,在中程(10-30km)水下多载波(MC)高速通信中具有良好的应用前景。 展开更多
关键词 水声信道 非对称升余弦信号 频移键控 多径抑制 多载波 水声通信
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Pressure Gradient Force,Saffman Lift,and Magnus Lift on the Fiber-like Particle in Fluid 被引量:5
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作者 朱泽飞 林建忠 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期23-27,共5页
Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, S... Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, Saffman lift,pressure gradient force, and then the dynamics modelhave been received. The numerical study of the simpleshear flow past the cylinders shows that the particles ’motion is controlled by the vortex. 展开更多
关键词 multi - phase FLUID FIBER - LIKE PARTICLE FORCE analysis
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1Tb/s高速光传输技术研究 被引量:5
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作者 张新全 程容 +1 位作者 杨奇 杨铸 《光通信技术》 CSCD 北大核心 2014年第5期1-4,共4页
针对光纤通信领域技术热点1Tb/s高速光传输开展研究,描述了1Tb/s光传输涉及的技术维度,分析了1Tb/s光传输的商用解决思路,重点研究了关键的高阶调制技术,并基于性能和可实现性提出具有指导意义的1Tb/s高速光传输商用技术解决方案。
关键词 光传输 高阶调制 多载波 谱效率
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总氮含量分析方法比较及黑龙江典型淡水养殖池塘和自然水域总氮含量的变化 被引量:4
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作者 黄丽 覃东立 +4 位作者 吴松 陈中祥 高磊 黄晓丽 王鹏 《水产学杂志》 CAS 北大核心 2018年第4期37-42,共6页
应用Multi N/C2100S分析仪与紫外-可见分光光度计对1个有证标准样品和6个实际水样总氮含量进行对比实验,予以验证。结果表明:两种仪器对已知浓度的有证标准样品测得的平均值接近真值,RSD<1%、相对误差<5%,结果准确度和精密度无显... 应用Multi N/C2100S分析仪与紫外-可见分光光度计对1个有证标准样品和6个实际水样总氮含量进行对比实验,予以验证。结果表明:两种仪器对已知浓度的有证标准样品测得的平均值接近真值,RSD<1%、相对误差<5%,结果准确度和精密度无显著差异。Multi N/C2100S分析仪可以高效、快速批量测定。5个月中4次监测6个实际水样总氮含量的结果为:白鱼泡水体中TN含量无显著变化;宾县1~#和3~#池塘水体含量逐月升高;5月稻田TN含量明显偏高,可能是水稻生长施肥所致;7月松花江水样TN含量高于其他月份,可能受养殖密度、模式、天气、投饵量、施肥量及周边农作物施药量的影响。 展开更多
关键词 总氮(TN) 紫外-可见分光光度计 multi N/C2100S分析仪 淡水养殖池塘 自然水域
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准优化PWM技术在级联型多电平变流器中的应用 被引量:2
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作者 杨向真 丁明 +1 位作者 苏建徽 茆美琴 《变频器世界》 2006年第2期59-62,共4页
级联型多电平变流器是目前高压变流器的主要拓扑结构之一,载波相移SPWM技术是级联型多电平变流器普遍采用的方法,但是这种方法的一个缺点是直流电压利用率较低,为了提高级联型多电平变流器的直流电压利用率,将准优化PWM技术应用于载波相... 级联型多电平变流器是目前高压变流器的主要拓扑结构之一,载波相移SPWM技术是级联型多电平变流器普遍采用的方法,但是这种方法的一个缺点是直流电压利用率较低,为了提高级联型多电平变流器的直流电压利用率,将准优化PWM技术应用于载波相移SPWM技术中,通过分析并利用MATLAB进行仿真,验证了这种方案的可行性。 展开更多
关键词 级联型多电平变流器 载波相移SPWM技术 准优化PWM技术 直流电压利用率
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基于训练序列的UFMC符号定时同步改进算法
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作者 余翔 周志义 +1 位作者 段思睿 陈和力 《电信科学》 2018年第5期7-12,共6页
针对通用滤波多载波(universal filtered multi-carrier,UFMC)系统采用滤波器而导致符号定时同步算法精确度偏低的问题,提出一种适合UFMC系统的符号定时同步改进算法。该算法考虑了滤波器对符号的影响,提出一种用于符号定时同步的新的... 针对通用滤波多载波(universal filtered multi-carrier,UFMC)系统采用滤波器而导致符号定时同步算法精确度偏低的问题,提出一种适合UFMC系统的符号定时同步改进算法。该算法考虑了滤波器对符号的影响,提出一种用于符号定时同步的新的训练序列结构,并给出相应的定时测度函数的计算式。新的训练序列结构消除了采用滤波器带来的平台效应,使得算法的定时估计性能得到改善。仿真结果表明,改进算法的定时测度函数曲线在起始点有一个尖峰,提高了定时估计的精确度。 展开更多
关键词 通用滤波多载波 符号定时同步 训练序列 定时测度函数
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DO网络性能提升优化法
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作者 金志涛 《计算机光盘软件与应用》 2011年第14期105-105,共1页
随着唐山电信EVDO网络的开通和持续建设,唐山电信的EVDO业务用户规模也在不断发展壮大,而用户规模的不断增大及分布范围的扩大,用户反映了很多问题,主要集中在网速慢、无法接入网络和频繁掉线三大类上,对此三类问题进行针对化的优... 随着唐山电信EVDO网络的开通和持续建设,唐山电信的EVDO业务用户规模也在不断发展壮大,而用户规模的不断增大及分布范围的扩大,用户反映了很多问题,主要集中在网速慢、无法接入网络和频繁掉线三大类上,对此三类问题进行针对化的优化,并总结了几类除El常优化手段外的经验。 展开更多
关键词 EVDO 网络性能 措施 网遍隧 接入 掉线 扇区分裂 多载波 大功率
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从欧美日数字电视标准发展中看中国数字电视标准的发展
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作者 符逸 《电脑与电信》 2008年第6期86-87,90,共3页
本文从数字电视技术标准的意义谈起,分别回顾了美国ATSC标准、欧洲DVB标准、日本ISDB标准的制定和发展,以及我国数字广播电视标准化工作的现状,介绍了数字电视地面系统标准及其关键技术。
关键词 数字电视 标准 ATSC DVB ISDB 多载波 单载波
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宽带码分多址多载频扩容策略
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作者 郑劲松 《唐山师范学院学报》 2013年第2期53-54,共2页
从WCDMA网络的容量需要出发,提出多载频组网的必要性,分析多载频组网需要解决的问题,提出影响WCDMA网络性能优劣的关键技术,包括负荷均衡策略、空闲态策略、硬指配策略、硬切换策略等。
关键词 多载频 容量 硬指配
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Some Practical Issues Regarding Java Programming
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作者 Ming-fang Wang Department of Computer Science, University of Central ArkansasConway, Arkansas 72035 wangm @ panda.cs.uca.eduWu JieShanghai Institute of Computing Tech. Shanghai, China 200040 Telephone: 62520070 《计算机工程》 CAS CSCD 北大核心 1996年第S1期106-121,共16页
Java programming language is a major . new development which involves object-oriented programming and computer networking. Here, several examples of Java programs are presented. These examples show some major features... Java programming language is a major . new development which involves object-oriented programming and computer networking. Here, several examples of Java programs are presented. These examples show some major features that Java language provides, such as multi-thread, exception handling, network application writing, and the usage of Java applets. This article also shows some ways of setting up a Java language programming environment. All these examples are correct and ready to run. 展开更多
关键词 Java programming/object- ORIENTED programming/multi - THREAD
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ANALYSIS OF PSYCHOLOGIC HEALTH STATE AND INFLUENCING FACTORS IN COLLEGE AND SECONDARY SCHOOL STUDENTS IN SHAANXI PROVINCE
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作者 高成阁 王友平 +1 位作者 谭新 亢万虎 《Academic Journal of Xi'an Jiaotong University》 2000年第2期168-171,共5页
Objective The psychologic health level of college and secondaryschool students and the relevant factors were investigated to scientific basis and guidance for school mental health work.Methods Standard 1251 cases were... Objective The psychologic health level of college and secondaryschool students and the relevant factors were investigated to scientific basis and guidance for school mental health work.Methods Standard 1251 cases were drawn from 1‰ of students in colleges and middle schools of Shaanxi province.Taking 14 psychic health level indexes in SCL 90 as dependent variable and 109 indexes of psychic health back ground as in dependent variable, multi factor analyses have been made.Results 22.6% of students had relatively serious psychological problems.The score of SCL 90 in females was a little bit higher than that in males.The scores of students at both universities and senior middle schools were higher than that in junior middle schools students.The score of SCL 90 of students who came from the countryside was higher than that of city students.The score of the whole students was higher than that of the normal.The students with psychic problems showed obsession,interpersonal sensitivity,depression,anxiety,paranoia and hostility.Factor analysis showed that influencing factors included history of positive individual risking behavior,physical conditions,grade,address,family influences,menses and sexual prombles,bad relation with others,poor self assessment.Conclusion The psychologic health level of the students investigated is lower than that of the whole society.The factors,which hamper psychic health of students, are biological,psychological and social in nature. 展开更多
关键词 school psychologic health SCL -90 multi factor analysis influencing factors
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