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Cost of Medical Treatment for Primary Open-Angle Glaucoma in Relation to Patients’ Income and Its Impact on the Prognosis of the Disease, in Bouaké University Hospital
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作者 Yves Ouattara Liliane Ella Godé +5 位作者 Zana Diabaté Franck Hermann Koffi Mamadou Korka Diallo Philippe Emile France Koffi Bilé Diomandé François Gossé Ibrahim Abib Diomandé 《Open Journal of Ophthalmology》 2024年第1期8-17,共10页
Introduction: Medical treatment for POAG is continuous and lifelong treatment. The aim of this study was to evaluate the relationship between the cost of this treatment and patients’ income and the impact of this rel... Introduction: Medical treatment for POAG is continuous and lifelong treatment. The aim of this study was to evaluate the relationship between the cost of this treatment and patients’ income and the impact of this relationship on treatment compliance. Materials and Methods: Prospective cross-sectional study with a descriptive aim covering sociodemographic data, average incomes, and direct and indirect costs of treatment of 57 patients followed for POAG during the period from January 1, 2012, to December 31, 2016 (5 years). Results: The patients were aged 25 to 77 years (mean = 54.4 years) with a male predominance (sex ratio = 1.5). Retirees were the most represented (26.32%), followed by workers in the informal sector (14.04%) and housewives (12.28%). Patients who had an annual income less than or equal to 900,000 CFA francs (€1370.83) per year represented 56.14% and those who did not have health coverage represented 57.89%. The treatment was monotherapy (64.91%), dual therapy (31.58%) or triple therapy (3.05%) and the average ratio of “annual cost of treatment to annual income” was 0.56 with for maximum 2.23 and 0.02 as minimum. Patients who considered the cost of treatment unbearable for their income represented 78.95%. Conclusion: Prevention of blindness due to glaucoma requires early detection but also the establishment of health coverage mechanisms to improve compliance with medical treatment. In addition, consideration should be given to the development of glaucoma surgery in our country, the indication of which could be the first intention in certain patients, considering for those patients, the geographical and financial accessibility of medical treatment. . 展开更多
关键词 Primary open-Angle Glaucoma Treatment Cost Medical Treatment INCOME BLINDNESS
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Epidemiological, Clinical, Therapeutic and Evolutive Profile of Primary Open-Angle Glaucoma in a Cameroonian Population
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作者 Christelle Domngang Fabiola Makamwe Tagne +3 位作者 Leonard Tedong Chantal Ngoune Nanfack Caroline Mvilongo Giles Kagmeni 《Open Journal of Ophthalmology》 2024年第2期93-102,共10页
Background: Sub-Saharan Africa has the highest prevalence of primary open-angle glaucoma (POAG), at 4.2%. The efficacy of medical treatment has been demonstrated and remains one of the treatments of choice for POAG. H... Background: Sub-Saharan Africa has the highest prevalence of primary open-angle glaucoma (POAG), at 4.2%. The efficacy of medical treatment has been demonstrated and remains one of the treatments of choice for POAG. However, in sub-Saharan Africa, its effectiveness has many challenges, due to multiple factors, including cost and access to care. Thus, the present study aimed to determine the epidemiological, clinical, therapeutic and evolutive profile of primary open-angle glaucoma patients. Methodology: A descriptive cross-sectional study was carried out in two hospitals in western Cameroon. Epidemiological, clinical, therapeutic, and evolutionary data on intraocular pressure at one year after medical treatment were analyzed. SPSS version 23 software was used for statistical analysis, with a significant p-value set at 5%. Results: A total of 201 patients with POAG were included in the study. The population comprised 100 men and 101 women, with a mean age of 54 ± 12 years. At diagnosis, the mean intraocular pressure was 23.9 ± 8.70 mmHg for the right eye and 25.5 ± 9.57 mmHg for the left eye. The mean cup/disc ratio was 0.64 ± 0.2 [0.2-1] and 0.67 ± 0.19 [02-1] in the right and left eyes, respectively. Monotherapy was the most prescribed treatment [59.2%]. After one year of treatment, intraocular pressure was reduced by 15.5% with beta-blockers, 23.66% with prostaglandins, 19.11% with carbonic anhydrase inhibitors, 35, 92% with beta-blockers and carbonic anhydrase inhibitors, 25.92% with beta-blockers and prostaglandins, 48.03% with carbonic anhydrase inhibitors and prostaglandin agonists, and 38.77% with triple therapy. Taking glaucoma severity into account, a significant reduction in intraocular pressure at one year was observed in all participants [p 0.05]. However, the target pressure was obtained in 47%, 20% and 14% of eyes suffering of mild, moderate, and severe grade of POAG respectively. Conclusion: In the present study, there was a significant reduction in intraocular pressure after one year of medical treatment. However, the reduction in intraocular pressure does not allow the target pressure to be reached in severe forms. Thus, alternatives to the medical treatment of POAG should be discussed early in the present context. . 展开更多
关键词 Primary open-Angle Glaucoma Medical Treatment Intraocular Pressure Target Intraocular Pressure
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Study on the Application of Real-Time Drone Monitoring in Ordos Open-Pit Coal Mine
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作者 Junyi Wu Weizheng Wang Xuesong Ni 《Open Journal of Applied Sciences》 CAS 2023年第4期483-495,共13页
In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detecti... In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detection by existing conventional monitoring methods, this paper establishes an open-pit mine monitoring data set, and proposes a real-time intelligent monitoring model based on UAV. The reasoning component with strong computing power and low power consumption is selected, and the lightweight object detection model is selected for the experiment. A quantitative standard of dynamic energy consumption detection by evaluation algorithm is proposed. Through experimental comparison, it is found that YOLOv4-tiny has the highest comprehensive grade in detection accuracy, speed, energy consumption and other aspects, which is suitable for application in the above model. 展开更多
关键词 open-Pit Mine Safety Monitoring UAV Object Detection
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Software Metric Analysis of Open-Source Business Software
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作者 Charles W. Butler 《Journal of Software Engineering and Applications》 2023年第5期144-153,共10页
Over the past decade, open-source software use has grown. Today, many companies including Google, Microsoft, Meta, RedHat, MongoDB, and Apache are major participants of open-source contributions. With the increased us... Over the past decade, open-source software use has grown. Today, many companies including Google, Microsoft, Meta, RedHat, MongoDB, and Apache are major participants of open-source contributions. With the increased use of open-source software or integration of open-source software into custom-developed software, the quality of this software component increases in importance. This study examined a sample of open-source applications from GitHub. Static software analytics were conducted, and each application was classified for its risk level. In the analyzed applications, it was found that 90% of the applications were classified as low risk or moderate low risk indicating a high level of quality for open-source applications. 展开更多
关键词 open-Source Software Software Quality Software Risks Cyclomatic Complexity Essential Complexity Module Design Complexity Design Complexity Integration Complexity Local Data Complexity Public Global Data Complexity Parameter Data Complexity Risk Score Risk Classification
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基于Open-L系统及递归表示的虚拟植物模型 被引量:13
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作者 唐卫东 刘昌鑫 +1 位作者 李萍萍 卢章平 《农业机械学报》 EI CAS CSCD 北大核心 2009年第1期167-170,共4页
构建符合植物学规律的虚拟植物模型是动态模拟植物生长发育的基础。为增强Open-L系统功能及克服其应用时的繁琐与不足,建立了植物与其生长环境的信息交互模型,并采用Open-L系统的递归表示来构建虚拟植物模型。通过实例验证表明,该模型... 构建符合植物学规律的虚拟植物模型是动态模拟植物生长发育的基础。为增强Open-L系统功能及克服其应用时的繁琐与不足,建立了植物与其生长环境的信息交互模型,并采用Open-L系统的递归表示来构建虚拟植物模型。通过实例验证表明,该模型能有效地模拟植物受外部环境作用下的生长过程。 展开更多
关键词 虚拟植物 open-L系统 递归表示 模型
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基于Open-GL组件技术的采矿模拟系统 被引量:6
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作者 贾明涛 潘长良 +1 位作者 王李管 侯林惠 《中南工业大学学报》 CSCD 北大核心 2003年第1期11-15,共5页
冬瓜山铜矿是目前国内发现的埋深最大、有岩爆倾向的缓倾斜厚度大的铜矿床,为了安全、高效生产,开发一套综合矿床开采模型对该矿山进行管理、调度、分析、控制及模拟.作者对其中的一个子系统“采矿过程动态模拟系统”的技术开发进行了研... 冬瓜山铜矿是目前国内发现的埋深最大、有岩爆倾向的缓倾斜厚度大的铜矿床,为了安全、高效生产,开发一套综合矿床开采模型对该矿山进行管理、调度、分析、控制及模拟.作者对其中的一个子系统“采矿过程动态模拟系统”的技术开发进行了研究.其过程是:通过系统分析,利用Open-GL图形库开发了适用于Delphi的通用三维图形环境及基本图元组件;分析并建立了开采轮数与开采步数之间的数学关系式;根据矿体项、底板倾角设定合理的单元块尺寸,以便既能精确模拟矿体边界形态,又能减少系统处理工作量,提高系统运行效率;运用时钟组件实现模拟过程的动态效果.利用这些技术,开发了一个采矿过程动态模拟系统.实践结果表明,该系统运行效果良好. 展开更多
关键词 组件技术 采矿模拟系统 open-GL 图形库 冬瓜山铜矿 矿床开采
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多Open-Shop生产线协调生产计划的模型及仿真 被引量:2
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作者 蒋珉 李敏 《系统仿真学报》 EI CAS CSCD 北大核心 2007年第11期2421-2424,2433,共5页
研究了一类带有限缓冲区的上游多Open-Shop生产线协调生产计划问题,建立了上下游生产线产品关联结构,并以此为研究对象,得到了成本最低生产计划模型。通常该类模型是非线性的且维数很大,给求解带来了困难。考虑到下游装配线的生产情况,... 研究了一类带有限缓冲区的上游多Open-Shop生产线协调生产计划问题,建立了上下游生产线产品关联结构,并以此为研究对象,得到了成本最低生产计划模型。通常该类模型是非线性的且维数很大,给求解带来了困难。考虑到下游装配线的生产情况,提出一种不考虑主成品的模型简化方法,并采用遗传算法进行求解。该简化方法可以大大减少模型维数,提高求解速度。仿真结果表明,建立的模型及采用的算法是合理的,模型简化方法是有效可行的。 展开更多
关键词 open-Shop 生产计划 有限缓冲区 同步 遗传算法
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A Novel Open-winding Permanent Magnetic Starter-generator 被引量:13
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作者 魏佳丹 周波 +3 位作者 韩楚 邓清唐 史明明 刘颖 《中国电机工程学报》 EI CSCD 北大核心 2011年第36期I0008-I0008,243,共1页
针对永磁电机应用于车载起动/发电系统时存在的电压调节困难、适用转速范围窄、功率因数较低等问题,提出一种新型永磁车载起动/发电系统。通过引入绕组开路型永磁电机,绕组一端接整流桥形成输出直流侧,另一端接逆变桥形成控制端,... 针对永磁电机应用于车载起动/发电系统时存在的电压调节困难、适用转速范围窄、功率因数较低等问题,提出一种新型永磁车载起动/发电系统。通过引入绕组开路型永磁电机,绕组一端接整流桥形成输出直流侧,另一端接逆变桥形成控制端,构成具有宽转速范围和高效率的永磁电机起动/发电系统。分析该系统的起动、发电一体化工作原理,给出了通过逆变侧变换器实现发电机电压、电流控制的方案。仿真和实验结果表明,该新型车载起动/发电系统具有优良的发电调压控制性能,并且适应较宽的转速范围。 展开更多
关键词 永磁起动机 永磁发电机 开放式 绕组 起动发电机 电压调节 功率因数 生成模式
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基于Open-L系统的植物结构功能模型研究 被引量:15
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作者 唐卫东 李萍萍 卢章平 《计算机应用研究》 CSCD 北大核心 2007年第3期94-96,99,共4页
为了真实地模拟植物生长发育过程,引入了Open-L系统建模理论。在植物形态发生模型的基础上,根据植物生长时其形态与生理特性及环境之间的相互作用,构建了综合考虑植物结构与功能的虚拟植物模型,再根据该模型有效组织了植物生长过程中的... 为了真实地模拟植物生长发育过程,引入了Open-L系统建模理论。在植物形态发生模型的基础上,根据植物生长时其形态与生理特性及环境之间的相互作用,构建了综合考虑植物结构与功能的虚拟植物模型,再根据该模型有效组织了植物生长过程中的数据信息,并建立植物生长的可视化流程。最后,开发一个原型系统验证了该模型的可行性和有效性。 展开更多
关键词 开放式L系统 结构功能模型 可视化
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Social functions of relaxed open-mouth display in golden snub-nosed monkeys(Rhinopithecus roxellana) 被引量:2
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作者 You-Ji Zhang Yi-Xin Chen +5 位作者 Hao-Chun Chen Yuan Chen Hui Yao Wan-Ji Yang Xiang-Dong Ruan Zuo-Fu Xiang 《Zoological Research》 SCIE CAS CSCD 2019年第2期113-120,共8页
Relaxed open-mouth display serves important social functions in relation to submission, reconciliation affiliation and reassurance among non-human primate societies; however, quantitative evidence on this behavior rem... Relaxed open-mouth display serves important social functions in relation to submission, reconciliation affiliation and reassurance among non-human primate societies; however, quantitative evidence on this behavior remains insufficient among multi-level social groups. From July to November 2016, we examined four potential functions of the relaxed open-mouth display during pairwise, intra-unit social interactions among 18 free-ranging adult and sub-adult golden snub-nosed monkeys(Rhinopithecus roxellana) who belonged to three one-male, multi-female units(OMU) at Dalongtan, Shennongjia National Park China. Results showed that: compared with no relaxed open-mouth display,(1) the occurrence of displacement by a dominant individual approaching a subordinate was lower and the distance of the subordinate to the approaching dominant was shorter when the subordinate showed open-mouth display;(2) relaxed open-mouth display reduced the probability of continued attack for victims of aggression and allowed victims to achieve closer proximity to the aggressor during post-conflict periods;(3) relaxed open-mouth display by dominant individuals allowed them to achieve closer proximity to subordinates; and(4) the exchange of relaxed open-mouth display had a greater impact on the outcome of interactions than one individual alone giving this signal. These findings suggest that relaxed open-mouth display serves important functions regarding submission, reconciliation, affiliation and reassurance in coordinating social interactions within OMUs in golden snub-nosed monkeys. 展开更多
关键词 GOLDEN snub-nosed monkey open- MOUTH Submission Reconciliation Affiliation REASSURANCE
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Open-MP与并行程序设计 被引量:2
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作者 陈峻 陈宏建 秦玲 《计算机科学》 CSCD 北大核心 2003年第11期133-135,共3页
1引言 随着并行处理技术的发展,并行计算已日益成为现代科学与工程计算必不可少的工具.工作站机群(COW)以及大规模并行处理机(MPP)的发展与应用使得并行计算向高性能、可扩放、通用性发展.
关键词 MPI 并行程序设计
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宁心解郁胶囊对慢性应激抑郁模型大鼠Open-Field行为的影响 被引量:2
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作者 孙亚男 邹忆怀 朱陵群 《天津中医药》 CAS 2014年第1期42-46,共5页
[目的]探讨宁心解郁胶囊的抗抑郁作用及可能的机制。[方法]以孤养加慢性轻度不可预见性应激方法建立大鼠抑郁模型,用Open-Field方法进行行为学评定,观察模型大鼠给药前后的行为学变化。[结果]经过孤养加慢性轻度不可预见性应激方法造模... [目的]探讨宁心解郁胶囊的抗抑郁作用及可能的机制。[方法]以孤养加慢性轻度不可预见性应激方法建立大鼠抑郁模型,用Open-Field方法进行行为学评定,观察模型大鼠给药前后的行为学变化。[结果]经过孤养加慢性轻度不可预见性应激方法造模后的大鼠,Open-Field行为学评定中模型组大鼠的总路程、平均速度、中央活动路程、中央活动时间、各角的活动路程和时间均较空白组有统计学差异(P<0.05)。治疗后大鼠的总活动路程、平均速度、中央活动时间、中央活动路程、下边活动路程、下边活动时间、各角的活动路程和时间均较模型组有统计学差异(P<0.05),活动路程较模型组增加,活动时间较模型组增加,且以中剂量组效果显著。[结论]宁心解郁胶囊具有抗抑郁作用,对大鼠抑郁行为有明显改善。 展开更多
关键词 宁心解郁胶囊 慢性应激抑郁模型 Open—Field实验 行为学
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Performance evaluation of open-graded epoxy asphalt concrete with two nominal maximum aggregate sizes 被引量:6
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作者 罗桑 钱振东 薛永超 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第11期4483-4489,共7页
Open-graded friction course(OGFC) is applied to pavement surfaces to increase driving safety under wet conditions, and recently, to reduce tire/pavement noise. The durability of OGFC, however, has been a concern since... Open-graded friction course(OGFC) is applied to pavement surfaces to increase driving safety under wet conditions, and recently, to reduce tire/pavement noise. The durability of OGFC, however, has been a concern since conventional OGFC mixes last typically less than ten years before major maintenance or rehabilitation is needed. This work investigates a new open-graded asphalt mixture that uses epoxy asphalt as binder to improve mix durability. One type of epoxy asphalt that has been successfully applied to dense-graded asphalt concrete for bridge deck paving was selected. A procedure of compacting the mix into slab specimens was developed and a series of laboratory tests were conducted to evaluate the performance of the new mix, including Cantabro loss, permeability, friction, shear strength, and wheel rutting tests. Results show superior overall performance of the open-graded epoxy asphalt mix compared to conventional open-graded asphalt mix. There are also preliminary indications that the OGFC mix with 4.75-mm NMAS gradation can improve the resistance performance to raveling, while the OGFC mix with 9.5-mm NMAS gradation can improve the performance of surface friction at a high slip speed. 展开更多
关键词 open-graded CONCRETE epoxy ASPHALT CONCRETE nomina
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OPEN-2000在威海电业局的应用 被引量:1
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作者 刘天斌 刘斌 《电力系统自动化》 EI CSCD 北大核心 1999年第15期53-54,共2页
关键词 电力系统 调度自动化 服务器 open-2000 电业局
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Numerical Modeling of the Compression Process of Elastic Open-cell Foams 被引量:6
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作者 ZHANG Jia-lei LU Zi-xing 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第3期215-222,共8页
The random models of open-cell foams that can reflect the actual cell geometrical properties are constructed with the Voronoi technique. The compression process of elastic open-cell foams is simulated with the nonline... The random models of open-cell foams that can reflect the actual cell geometrical properties are constructed with the Voronoi technique. The compression process of elastic open-cell foams is simulated with the nonlinear calculation module of finite element analysis program. In order to get the general results applicable to this kind of materials, the dimensionless compressive stress is used and the stress-strain curves of foam models with different geometrical properties are obtained. Then, the influences of open-cell geometrical properties, including the shape of strut cross section, relative density and cell shape irregularity, on the compressive nonlinear mechani- cal performance are analyzed. In addition, the numerical results are compared with the predicted results of cubic staggering model. Nu- merical results indicate that the simulated results reflect the compressive process of foams quite well and the geometrical properties of cell have significant influences on the nonlinear mechanical behavior of foams. 展开更多
关键词 Voronoi technique open-cell foam NONLINEAR compressive stress
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OPEN-2000系统在县级电网调度中的应用
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作者 刘志雄 邝以云 方富淇 《广东电力》 2001年第3期58-59,共2页
三水市电网是县级电网 ,由于其发展快速 ,原采用的SINAUTSPECTRUMSCADA系统容量及功能已不能满足电网调度的需要 ,后改用南瑞集团公司的OPEN 2 0 0 0系统 ,这是该系统首次用在县级电网上。为此 ,介绍该系统的功能和特点。OPEN 2 0 0 0... 三水市电网是县级电网 ,由于其发展快速 ,原采用的SINAUTSPECTRUMSCADA系统容量及功能已不能满足电网调度的需要 ,后改用南瑞集团公司的OPEN 2 0 0 0系统 ,这是该系统首次用在县级电网上。为此 ,介绍该系统的功能和特点。OPEN 2 0 0 0系统投入运行后 ,大大提高了三水市电网调度的自动化水平。实践证明 。 展开更多
关键词 open-2000系统 SCADA系统 电网调度自动化
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Prevalence of Open-angle Glaucoma in Southwestern China: the Yongchuan Glaucoma Study 被引量:3
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作者 李华 张永烨 +7 位作者 刘世纯 贺翔鸽 李崇金 李春华 李革 徐霁 邬羽飞 宋胜仿 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第1期137-141,共5页
This study examined the prevalence of primary open-angle glaucoma(POAG) among residents aged ≥50 years living in Yongchuan district of Chongqing. Stratified cluster sampling was employed in random selection to esti... This study examined the prevalence of primary open-angle glaucoma(POAG) among residents aged ≥50 years living in Yongchuan district of Chongqing. Stratified cluster sampling was employed in random selection to estimate the prevalence of glaucoma from April to June, 2005. Twenty-nine villages or neighborhood communities were randomly selected in urban area(Zhongshan Road), suburban area(Shanjiao Town) and exurban area(Zhutuo Town) of this district. All the respondents underwent detailed ophthalmic examinations. The examinations included questionnaire investigation, visual acuity test, naked-eye examination, measurement of peripheral anterior chamber depth(Van Herrick's technique), detection of intraocluar pressure(IOP) with a Perkins hand-held applanation tonometer(HA-2) and examination of the optic disc by using a 78 diopters(D) lens(including the cup-disc ratio, cup/disc ratio asymmetries, horizontal and vertical diameter, notching and optic disc hemorrhages). A total of 5938 residents were actually examined, and the response rate was 85.19%. The crude prevalence of POAG was 0.86%(n=51/5938, 95% CI 0.64%–1.11%). There were 24 males and 27 females in the glaucoma group. The glaucoma prevalence was not significant different in case number between the male and female subjects(P=0.4900). Furthermore, no association between age or schooling and POAG was noted(P=0.8030, 0.0734). Out of 51 subjects with POAG, unilateral glaucoma-related blindness occurred in 38 subjects(74.5%) and bilateral glaucoma-related blindness was found in 7 subjects(13.7%). This study exhibited that the prevalence of POAG was 0.86% among residents aged ≥50 years living in Yongchuan District of Chongqing. The vision loss caused by POAG in this population was obviously higher than that previously reported in other studies. Glaucoma management, detection of affected persons and handling of the burden of glaucoma should be the priorities of the agenda of local health authorities of Western China. 展开更多
关键词 primary open-angle glaucoma PREVALENCE BLINDNESS
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Application of open-pit and underground mining technology for residual coal of end slopes 被引量:9
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作者 CHE, Zhaoxue YANG, Hong 《Mining Science and Technology》 EI CAS 2010年第2期266-270,共5页
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining tech... Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized. 展开更多
关键词 integrated open-pit and underground mining end-slope resource recovery economic benefit surface coal mine
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Dispersion compensation in an open-loop all-optical chaotic communication system 被引量:3
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作者 刘慧杰 任斌 冯久超 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期138-144,共7页
The optical chaotic communication system using open-loop fiber transmission is studied under strong injection conditions. The optical chaotic communication system with open-loop configuration is studied using fiber tr... The optical chaotic communication system using open-loop fiber transmission is studied under strong injection conditions. The optical chaotic communication system with open-loop configuration is studied using fiber transmission under strong injection conditions. The performances of fiber links composed of two types of fiber segments in different dispersion compensation maps are compared by testing the quality of the recovered message with different bit rates and encrypted by chaotic modulation (CM) or chaotic shift keying (CSK). The result indicates that the performance of the pre-compensation map is always worst. Two types of symmetrical maps are identical whatever the encryption method and bit-rate of message are. For the transmitting and the recovering of message of lower bit rate (1 Gb/s), the post-compensation map is the best scheme. However, for the message of higher bit rate (2.5 Gb/s), the parameters in communication system need to be modified properly in order to adapt to the high-speed application. Meanwhile, two types of symmetrical maps are the best scheme. In addition, the CM method is superior to the CSK method for high-speed applications. It is in accordance with the result in a back-to-back configuration system. 展开更多
关键词 chaotic communication dispersion compensation semiconductor lasers strong injection open-loop configuration
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INVESTIGATION ON KANE DYNAMIC EQUATIONSBASED ON SCREW THEORY FOR OPEN-CHAIN MANIPULATORS 被引量:3
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作者 刘武发 龚振邦 汪勤悫 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第5期627-635,共9页
First,screw theory,product of exponential formulas and Jacobian matrix are introduced.Then definitions are given about active force wrench,inertial force wrench,partial velocity twist,generalized active force,and gene... First,screw theory,product of exponential formulas and Jacobian matrix are introduced.Then definitions are given about active force wrench,inertial force wrench,partial velocity twist,generalized active force,and generalized inertial force according to screw theory.After that Kane dynamic equations based on screw theory for open-chain manipulators have been derived. Later on how to compute the partial velocity twist by geometrical method is illustrated. Finally the correctness of conclusions is verified by example. 展开更多
关键词 screw theory partial velocity twist open-chain manipulator Kane dynamic equation
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