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Effect of low-degree astigmatism on the objective visual quality
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作者 Ling-Ying Ye Shu-Feng Li +2 位作者 Jing-Jing Zuo Jin Li Hui-Xiang Ma 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1086-1093,共8页
AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corr... AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality. 展开更多
关键词 low-degree astigmatism objective visual quality Optical Quality Analysis System
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Distributed Stochastic Optimization with Compression for Non-Strongly Convex Objectives
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作者 Xuanjie Li Yuedong Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期459-481,共23页
We are investigating the distributed optimization problem,where a network of nodes works together to minimize a global objective that is a finite sum of their stored local functions.Since nodes exchange optimization p... We are investigating the distributed optimization problem,where a network of nodes works together to minimize a global objective that is a finite sum of their stored local functions.Since nodes exchange optimization parameters through the wireless network,large-scale training models can create communication bottlenecks,resulting in slower training times.To address this issue,CHOCO-SGD was proposed,which allows compressing information with arbitrary precision without reducing the convergence rate for strongly convex objective functions.Nevertheless,most convex functions are not strongly convex(such as logistic regression or Lasso),which raises the question of whether this algorithm can be applied to non-strongly convex functions.In this paper,we provide the first theoretical analysis of the convergence rate of CHOCO-SGD on non-strongly convex objectives.We derive a sufficient condition,which limits the fidelity of compression,to guarantee convergence.Moreover,our analysis demonstrates that within the fidelity threshold,this algorithm can significantly reduce transmission burden while maintaining the same convergence rate order as its no-compression equivalent.Numerical experiments further validate the theoretical findings by demonstrating that CHOCO-SGD improves communication efficiency and keeps the same convergence rate order simultaneously.And experiments also show that the algorithm fails to converge with low compression fidelity and in time-varying topologies.Overall,our study offers valuable insights into the potential applicability of CHOCO-SGD for non-strongly convex objectives.Additionally,we provide practical guidelines for researchers seeking to utilize this algorithm in real-world scenarios. 展开更多
关键词 Distributed stochastic optimization arbitrary compression fidelity non-strongly convex objective function
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Large-field objective lens for multi-wavelength microscopy at mesoscale and submicron resolution
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作者 Xin Xu Qin Luo +7 位作者 Jixiang Wang Yahui Song Hong Ye Xin Zhang Yi He Minxuan Sun Ruobing Zhang Guohua Shi 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第6期41-56,共16页
Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 mm.This restriction poses a challenge when attempting to simultaneously anal... Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 mm.This restriction poses a challenge when attempting to simultaneously analyze various parts of a sample,such as different brain areas.In addition,conventional objective lenses struggle to perform consistently across the required range of wavelengths for brain imaging in vivo.Here we present a novel mesoscopic objective lens with an impressive field of view of 8 mm,a numerical aperture of 0.5,and a working wavelength range from 400 to 1000 nm.We achieved a resolution of 0.74μm in fluorescent beads imaging.The versatility of this lens was further demonstrated through high-quality images of mouse brain and kidney sections in a wide-field imaging system,a confocal laser scanning system,and a two-photon imaging system.This mesoscopic objective lens holds immense promise for advancing multi-wavelength imaging of large fields of view at high resolution. 展开更多
关键词 mesoscopic objective lens large field-of-view high resolution MULTI-WAVELENGTH wide-field microscopy confocal laser scanning microscopy
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Objective Model Selection in Physics: Exploring the Finite Information Quantity Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第5期1848-1889,共42页
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati... Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines. 展开更多
关键词 Comparative Uncertainty Finite Information Quantity Formulating a Model Measurement Accuracy Limit objective Model Selection
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Research on the Relationship between the School-Running Characteristics of Private Colleges and Universities and the Development Objectives of the Government
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作者 Lishuxian Zhao Xiaoxia Wu Zhuolin Zhu 《Journal of Contemporary Educational Research》 2024年第9期296-302,共7页
The development objectives of the Chinese government have a guiding effect on the school-running characteristics of private colleges and universities.This paper explores the relationship between the characteristics of... The development objectives of the Chinese government have a guiding effect on the school-running characteristics of private colleges and universities.This paper explores the relationship between the characteristics of private colleges and universities and the development objectives of the provincial government,using Jiangsu Province as a case study.All the schools have the consciousness of fully considering the development objectives of Jiangsu Province when formulating the school-running characteristics.Their characteristics all contain some training methods,training courses,or institutional construction aiming at the development objectives.Most universities can support the government’s objectives on employment and innovation.Only a third of the schools provide government support for science research.Private colleges and universities should make full use of the free and flexible advantages of private education,combine them with the continuous changes of policies and markets,and create clear,scientific,and dynamic school-running characteristics,in order to achieve long-term development. 展开更多
关键词 Development objectives of the government School-running characteristics Chinese Private colleges and universities
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Objectives of and Approaches to Ecological City Construction 被引量:2
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作者 潘文明 黄顺 《Journal of Landscape Research》 2010年第6期77-79,83,共4页
It has become a trend of the city development in the world to build up the ecological city with an ecological system that is balanced in structure,high-efficient in service function.Taking Suzhou as a case,the authors... It has become a trend of the city development in the world to build up the ecological city with an ecological system that is balanced in structure,high-efficient in service function.Taking Suzhou as a case,the authors believe that the construction of an ecological city is a process of the progressive and well-organized systematic development and of the ecological function consummation,which will require five stages to complete,including ecological hygiene,ecological security,ecological industry,ecological landscape,and ecological culture.The problems presently encountered in the construction of ecological city in Suzhou can be solved through the following approaches:(1) To rebuild the relationship between man and nature when the planning is worked out;(2) To observe the principle of ecology in city design;(3) To choose the local plant species in city afforestation;(4) To choose those plantlets with vigorous growth,good shape,and high survival rate,observing the growth rule of plant and paying much attention to forest landscape,ecological system and biological diversity,rationally allocating the plant species resources;(5) To aim at the implementation of the less-labor management even the zero-labor management. 展开更多
关键词 ECOLOGICAL CITY objectives APPROACHES
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Objective and subjective measures for sleep disorders 被引量:2
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作者 张琳 赵忠新 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第4期236-240,共5页
Subjective and objective measures of sleep structure or quality could help to characterize the chronic sleep disturbances, with relation to patients' risk factor profiles and co-morbidities. Studies have shown that d... Subjective and objective measures of sleep structure or quality could help to characterize the chronic sleep disturbances, with relation to patients' risk factor profiles and co-morbidities. Studies have shown that discrepancies can occur between subjective data regarding sleep disturbances and the impact of insomnia and objective assays, and surrogate markers of sleep and sleep disturbances. Both objective and subjective measures should be incorporated into clinic studies. It seems likely that sleep quality is represented by a combination of more than one subjective sleep parameter. Objective and subjective assessments of sleep quality may relate to different parameters. Future studies incorporated both subjective and objective measures could help to address the sleep disorders. 展开更多
关键词 objective measures subjective measures sleep disorders
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A multi-objective fuzzy optimization model for cropping structure and water resources and its method 被引量:3
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作者 马建琴 陈守煜 邱林 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期5-10,共6页
Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this... Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development. 展开更多
关键词 cropping structure multi objective fuzzy optimization fuzzy deciding weight agricultural water resources
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基于Stingray Objective Studio的防空C^3I显控系统界面开发
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作者 狄博 李进 雷英杰 《弹箭与制导学报》 CSCD 北大核心 2005年第SA期456-457,466,共3页
文中提出了用 Stingray Objective Studio 工具集来进行防空显控系统界面开发,使得开发人员将大量的时间和精力用于系统结构和数据处理算法上,这样不光降低了开发难度,也增强了系统的功能和稳定性。
关键词 STINGRAY objective STUDIO 防空 C^3I 显控系统
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Multi Objective Decision Making Method Based on Evaluation Criterion for Problems with Linear Value Function
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作者 蒋尚华 韩勇 徐南荣 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期114-121,共8页
A class of interactive multi objective decision making method by means of evaluation criterion is proposed for problems with linear value function,in which case,the decision maker(DM) usually has only unwhole infor... A class of interactive multi objective decision making method by means of evaluation criterion is proposed for problems with linear value function,in which case,the decision maker(DM) usually has only unwhole information of weights for objectives. The concept of fault measure of the evaluation criterion is proposed to measure the deviation of the evaluation criterion from the DMs preference structure.The approach to obtain an upper boundary of fault measure of an evaluation criterion,and the approach to modify the evaluation criterion to be one with smaller fault measure,and the approach to obtain a pre optimized objective set by evaluation criterion with certain fault measure are also proposed. 展开更多
关键词 multi objective decision making evaluation criterion fault measure of evaluation criterion pre optimized objective set
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Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗计划中的应用研究
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作者 陈宗友 曾华驱 +5 位作者 汤树奎 林启富 梁柱 赖春任 赵善辉 温尊北 《中国医学装备》 2023年第10期53-60,共8页
目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective... 目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective工具的情况下给每例患者设计治疗参考计划(MU_(ref));将使用MU Objective工具对MU_(ref)进行重新优化,分别设置MU_(ref)的MU的30%、50%、70%、90%和120%,分别命名为MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)。将治疗计划MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)分别与MU_(ref)进行配对t检验统计分析,比较两种治疗计划的靶区、危及器官(OAR)剂量分布和计划的MU。结果:使用MU Objective工具对参考计划优化MU后,与参考计划相比部分靶区和OAR剂量体积参数差异虽有统计学意义,但无临床意义。治疗计划参数为MU_(30%)、MU_(50%)、MU_(70%)和MU_(90%)时,与MU_(ref)比较计划MU平均分别减少21.5%、19.5%、16.6%和8%,差异有统计学意义(t=9.652,t=8.843,t=8.963,t=11.323;P<0.05)。在MU_(120%)时,治疗计划MU平均增加1.7%,但未显著提高靶区剂量覆盖。结论:对于鼻咽癌VMAT计划,使用Eclipse计划系统的MU Objective工具在减少计划MU的同时可获得与参考计划相似的剂量分布。MU Objective工具可作为鼻咽癌或其他部位VMAT计划的常规使用工具,以保证计划质量同时减少放射治疗计划的MU。 展开更多
关键词 容积调强放射治疗(VMAT) Eclispe计划系统 MU objective工具 机器跳数(MU)
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MULTI OBJECTIVE OPTIMIZATION USING GENETIC ALGORITHM WITH LOCAL SEARCH
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作者 戴晓晖 李敏强 寇纪淞 《Transactions of Tianjin University》 EI CAS 1998年第2期31-35,共5页
In this paper,we propose a hybrid algorithm for finding a set of non dominated solutions of a multi objective optimization problem.In the proposed algorithm,a local search procedure is applied to each solution gener... In this paper,we propose a hybrid algorithm for finding a set of non dominated solutions of a multi objective optimization problem.In the proposed algorithm,a local search procedure is applied to each solution generated by genetic operations.The aim of the proposed algorithm is not to determine a single final solution but to try to find all the non dominated solutions of a multi objective optimization problem.The choice of the final solution is left to the decision makers preference.High search ability of the proposed algorithm is demonstrated by computer simulation. 展开更多
关键词 multi objective genetic algorithm Pareto set local search
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Objective increment based metaheuristic for total flowtime minimization in no-wait flowshops
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作者 朱夏 李小平 王茜 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期168-173,共6页
To solve the NP-complete no-wait flowshop problems, objective increment properties are analyzed and proved for fundamental operations of heuristics. With these properties, whether a new generated schedule is better or... To solve the NP-complete no-wait flowshop problems, objective increment properties are analyzed and proved for fundamental operations of heuristics. With these properties, whether a new generated schedule is better or worse than the original one is only evaluated by objective increments, instead of completely calculating objective values as the traditional algorithms do, so that the computational time can be considerably reduced. An objective increment-based hybrid genetic algorithm (IGA) is proposed by integrating the genetic algorithm (GA) with an improved various neighborhood search (VNS)as a local search. An initial solution generation heuristic(ISG) is constructed to generate one individual of the initial population. An expectation value-based selection mechanism and a crossover operator are introduced to the mating process. The IGA is compared with the traditional GA and two best-so-far algorithms for the considered problem on 110 benchmark instances. An experimental results show that the IGA outperforms the others in effectiveness although with a little more time consumption. 展开更多
关键词 no-wait flowshops total flowtime objective increment hybrid genetic algorithm
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Two-Stage Interactive Multi-Objective Decision-Making Method Based on the Satisfactoriness Criterion
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作者 蒋尚华 江孝感 徐南荣 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期93-100,共8页
In this paper, for multi objective decision making, the defects on the commonly used interactive methods based on the satisfactoriness criterion is studied. Then a class of two stage interactive method based on the... In this paper, for multi objective decision making, the defects on the commonly used interactive methods based on the satisfactoriness criterion is studied. Then a class of two stage interactive method based on the satisfactoriness criterion is proposed for improvement with the satisfactoriness criterion being determined through the collection of the decision makers preference information. An application example is presented for illustration of applicability of the method. 展开更多
关键词 multi objective decision making satisfactoriness criterion collection of preference information
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Robust Airfoil Optimization with Multi-objective Estimation of Distribution Algorithm 被引量:7
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作者 钟小平 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2008年第4期289-295,共7页
A transonic airfoil designed by means of classical point-optimization may result in its dramatically inferior performance under off-design conditions. To overcome this shortcoming, robust design is proposed to find ou... A transonic airfoil designed by means of classical point-optimization may result in its dramatically inferior performance under off-design conditions. To overcome this shortcoming, robust design is proposed to find out the optimal profile of an airfoil to maintain its performance in an uncertain environment. The robust airfoil optimization is aimed to minimize mean values and variances of drag coefficients while satisfying the lift and thickness constraints over a range of Mach numbers. A multi-objective estimation of distribution algorithm is applied to the robust airfoil optimization on the base of the RAE2822 benchmark airfoil. The shape of the airfoil is obtained through superposing ten Hick-Henne shape functions upon the benchmark airfoil. A set of design points is selected according to a uniform design table for aerodynamic evaluation. A Kriging model of drag coefficient is constructed with those points to reduce computing costs. Over the Mach range from 0.7 to 0.8, the airfoil generated by the robust optimization has a configuration characterized by supercritical airfoil with low drag coefficients. The small fluctuation in its drag coefficients means that the performance of the robust airfoil is insensitive to variation of Mach number. 展开更多
关键词 airfoil robust design multi-objective estimation of distribution algorithm uncertain environment drag FLUCTUATION
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China English——An Objective Existence as a Performance Variety
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作者 黄春燕 《语言与文化研究》 2008年第1期187-192,共6页
China English is an objective existence as a performance variety used in China.It is based on standard English and possesses Chinese characteristics.The Chinese characteristics of China English are reflected in the ph... China English is an objective existence as a performance variety used in China.It is based on standard English and possesses Chinese characteristics.The Chinese characteristics of China English are reflected in the phonology,vocabulary,syntax,rhetoric and text,particularly in the vocabulary.This essay will discuss the features of China English from the following three aspects: the development of English in China;the comparison between China English,Pidgin English and Chinese English and the Chinese words borrowed by English. 展开更多
关键词 China ENGLISH objective EXISTENCE PERFORMANCE VARI
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基于Objective-C的iPhone帧动画开发
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作者 王卫华 李娜 《安阳工学院学报》 2012年第2期45-47,52,共4页
随着各种苹果终端的广泛普及,适用于iPhone OS的软件开发也越来越受到人们的关注,本文除了对Objective-C语言进行了的介绍之外,重点针对实际iPhone开发帧动画资料的匮乏,提出解决方案,并将功能模块封装为组件,最终通过了播放帧动画的效... 随着各种苹果终端的广泛普及,适用于iPhone OS的软件开发也越来越受到人们的关注,本文除了对Objective-C语言进行了的介绍之外,重点针对实际iPhone开发帧动画资料的匮乏,提出解决方案,并将功能模块封装为组件,最终通过了播放帧动画的效果测试。 展开更多
关键词 objective-C 帧动画 开发
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Sediment distribution pattern mapped from the combination of objective analysis and geostatistics in the large shallow Taihu Lake, China 被引量:11
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作者 LUOLian-cong QINBo-qiang ZHUGuang-wei 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期908-911,共4页
Investigation was made into sediment depth at 723 irregularly scattered measurement points which cover all the regions in Taihu Lake, China. The combination of successive correction scheme and geostatistical method wa... Investigation was made into sediment depth at 723 irregularly scattered measurement points which cover all the regions in Taihu Lake, China. The combination of successive correction scheme and geostatistical method was used to get all the values of recent sediment thickness at the 69×69 grids in the whole lake. The results showed that there is the significant difference in sediment depth between the eastern area and the western region, and most of the sediments are located in the western shore-line and northern regimes but just a little in the center and eastern parts. The notable exception is the patch between the center and Xishan Island where the maximum sediment depth is more than 4.0 m. This sediment distribution pattern is more than likely related to the current circulation pattern induced by the prevailing wind-forcing in Taihu Lake. The numerical simulation of hydrodynamics can strong support the conclusion. Sediment effects on water quality was also studied and the results showed that the concentrations of TP, TN and SS in the western part are obviously larger than those in the eastern regime, which suggested that more nutrients can be released from thicker sediment areas. 展开更多
关键词 objective analysis GEOSTATISTICS sediment distribution Taihu Lake
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OBJECTIVE ANALYSIS OVER INDIAN REGION BY BRATSETH'SSUCCESSIVE CORRECTION SCHEME 被引量:5
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作者 S. K. Sinha S. G. Narkhedkar and S. Rajamani(Indian Institute of Tropical Meteorology, Pune 411008, India) 《Journal of Tropical Meteorology》 SCIE 1997年第1期35-41,共7页
Bratseth (1986) has proposed a successive correction scheme for numerical analysis where the solution converges towards the solution obtained by optimum interpolation. This paper presents the results of some experimen... Bratseth (1986) has proposed a successive correction scheme for numerical analysis where the solution converges towards the solution obtained by optimum interpolation. This paper presents the results of some experiments carried out over indian reston during summer monsoon period using this Bratseth’s method. The convergence of the method is investigated. 展开更多
关键词 Bratseth SCHEME objective ANALYSIS
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使用Objective-C编写机器人控制系统
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作者 张红 杨屏 +1 位作者 牛雅丽 贺伟 《办公自动化》 2017年第24期44-47,共4页
本文在<使用状态机实现的机器人控制系统>(办公自动化)的基础上,参考开源嵌入式领域的经验和借助及开源软件的成果,在机器人系统上实现基于Objective-C的可编程系统环境.。
关键词 状态机 控制系统 嵌入式 objective-C
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