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Anti-interference beam pattern design based on second-order cone programming optimization 被引量:1
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作者 戴文舒 鲍凯凯 +1 位作者 王萍 王黎明 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期255-260,共6页
When signal-to-interference ratio is low, the energy of strong interference leaked from the side lobe of beam pattern will infect the detection of weak target. Therefore, the beam pattern needs to be op... When signal-to-interference ratio is low, the energy of strong interference leaked from the side lobe of beam pattern will infect the detection of weak target. Therefore, the beam pattern needs to be optimized. The existing Dolph-Chebyshev weighting method can get the lowest side lobe level under given main lobe width, but for the other non-uniform circular array and nonlinear array, the low side lobe pattern needs to be designed specially. The second order cone programming optimization (SOCP) algorithm proposed in the paper transforms the optimization of the beam pattern into a standard convex optimization problem. Thus there is a paradigm to follow for any array formation, which not only achieves the purpose of Dolph-Chebyshev weighting, but also solves the problem of the increased side lobe when the signal is at end fire direction The simulation proves that the SOCP algorithm can detect the weak target better than the conventional beam forming. 展开更多
关键词 anti-interference beam pattern second-order cone programming optimization (SOCP) weak signal detection
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Program Development and Implementation of Landscape Pattern Indexes for Land Use Based on RS
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作者 谢宏全 戴娣 《Journal of Landscape Research》 2011年第8期26-27,46,共3页
Interpretation results of RS images were taken as the foundation, ETM RS images of July 15, 2009 as the data source, ENVI was applied for the preprocessing, Arc GIS used to finish the interpretation, master data obtai... Interpretation results of RS images were taken as the foundation, ETM RS images of July 15, 2009 as the data source, ENVI was applied for the preprocessing, Arc GIS used to finish the interpretation, master data obtained, and VB used to complete program development. 12 representative landscape pattern indexes were selected, Excel data used to create Access database, and VB used to complete the program development. Selection of landscape pattern indexes, program development process and program usage were summarized, through comparing its results with Excel calculation results, it was found that calculation results of this program were correct, the usage was convenient, so needs of most users could be satisfied. 展开更多
关键词 REMOTE SENSING LANDSCAPE pattern indexes DATABASE program development
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Detecting Design Patterns in Object-Oriented Program Source Code by Using Metrics and Machine Learning 被引量:4
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作者 Satoru Uchiyama Atsuto Kubo +1 位作者 Hironori Washizaki Yoshiaki Fukazawa 《Journal of Software Engineering and Applications》 2014年第12期983-998,共16页
Detecting well-known design patterns in object-oriented program source code can help maintainers understand the design of a program. Through the detection, the understandability, maintainability, and reusability of ob... Detecting well-known design patterns in object-oriented program source code can help maintainers understand the design of a program. Through the detection, the understandability, maintainability, and reusability of object-oriented programs can be improved. There are automated detection techniques;however, many existing techniques are based on static analysis and use strict conditions composed on class structure data. Hence, it is difficult for them to detect and distinguish design patterns in which the class structures are similar. Moreover, it is difficult for them to deal with diversity in design pattern applications. To solve these problems in existing techniques, we propose a design pattern detection technique using source code metrics and machine learning. Our technique judges candidates for the roles that compose design patterns by using machine learning and measurements of several metrics, and it detects design patterns by analyzing the relations between candidates. It suppresses false negatives and distinguishes patterns in which the class structures are similar. As a result of experimental evaluations with a set of programs, we confirmed that our technique is more accurate than two conventional techniques. 展开更多
关键词 Design patternS SOFTWARE Metrics MACHINE LEARNING OBJECT-ORIENTED programming SOFTWARE Maintenance
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Incremental Computation of Success Patterns of Logic Programs
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作者 Lunjin Lu 《Journal of Software Engineering and Applications》 2010年第3期198-207,共10页
A method is presented for incrementally computing success patterns of logic programs. The set of success patterns of a logic program with respect to an abstraction is formulated as the success set of an equational log... A method is presented for incrementally computing success patterns of logic programs. The set of success patterns of a logic program with respect to an abstraction is formulated as the success set of an equational logic program modulo an equality theory that is induced by the abstraction. The method is exemplified via depth and stump abstractions. Also presented are algorithms for computing most general unifiers modulo equality theories induced by depth and stump abstractions. 展开更多
关键词 INCREMENTAL Analysis SUCCESS patternS ABSTRACT Interpretation Depth ABSTRACT Stump ABSTRACTION Logic programS
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我国基层医疗资源配置失配度测算及其时空演变分析 被引量:1
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作者 李丽清 彭崟 +1 位作者 卢祖洵 袁岗 《中国全科医学》 北大核心 2025年第28期3495-3506,共12页
背景随着人口老龄化和慢性病患者比例的增加,人民群众对基层医疗资源的需求呈多样化、复杂化的态势。不同地区、不同人群对基层医疗资源的需求存在差异,部分地区面临基层医疗资源匮乏的问题,严重制约基层医疗卫生服务的覆盖率和质量,极... 背景随着人口老龄化和慢性病患者比例的增加,人民群众对基层医疗资源的需求呈多样化、复杂化的态势。不同地区、不同人群对基层医疗资源的需求存在差异,部分地区面临基层医疗资源匮乏的问题,严重制约基层医疗卫生服务的覆盖率和质量,极大影响居民的就医体验和健康状况。目的为推动基层医疗卫生服务体系高质量发展,引入健康距离模型,分析2011—2021年我国基层医疗资源配置失配度的时空演变过程,为合理制订区域卫生规划、优化医疗资源配置方案、提高基层医疗卫生服务能力、推动医疗卫生服务高质量发展提供参考。方法从卫生物力、人力、保障资源三个层面建立基层医疗资源失配度评价指标体系,从《中国卫生健康统计年鉴》《中国统计年鉴》获取数据,采用双层规划模型和健康距离模型测算2011—2021年基层医疗资源配置失配度。结果2011—2021年我国基层医疗资源配置整体失配度有明显的下降趋势,但是区际、省际间失配度差异不断扩大。2011年东、中、西部地区失配度平均值分别为0.633、0.624、0.754,分别为中度失配、轻度匹配和重度失配。2021年东、中、西部地区失配度平均值分别为0.479、0.522、0.639,分别为中度匹配、轻度匹配和中度失配。结论尽管我国基层医疗资源配置的整体失配度呈下降趋势,但仍然存在明显的差异,医疗资源配置的不均衡性仍在加剧。为持续优化基层医疗配置,推动基层医疗卫生服务体系高质量发展,提升我国医疗卫生体系的效能,需注重区域间资源配置的均衡性,因地制宜地制定差异化政策,以进一步优化医疗资源配置,提升基层医疗卫生服务的覆盖率和质量。 展开更多
关键词 卫生资源 资源配置 失配度 基层医疗资源配置 双层规划模型 时空格局
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二维板材排样问题的递归多块布局算法 被引量:1
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作者 潘卫平 樊治平 +1 位作者 黄敏 计明军 《计算机集成制造系统》 北大核心 2025年第6期2153-2164,共12页
针对矩形件二维板材排样问题,提出递归多块排样方式及其动态规划生成算法。递归多块排样方式将板材划分成多个块,然后递归地对每个块进行多块划分,直到每个新产生的块中排放一种最优矩形件为止。为了均衡考虑排样方式的计算复杂度和板... 针对矩形件二维板材排样问题,提出递归多块排样方式及其动态规划生成算法。递归多块排样方式将板材划分成多个块,然后递归地对每个块进行多块划分,直到每个新产生的块中排放一种最优矩形件为止。为了均衡考虑排样方式的计算复杂度和板材排样价值,对于一刀切排样问题将多块划分的块数定为两块,对于非一刀切排样问题将多块划分的块数定为5块。动态规划算法首先计算每个块中分别排放一种矩形件所得到的1阶多块排样方式的最大价值,然后计算每个块中分别排放一个1阶多块排样方式得到的2阶多块排样方式的最大价值,以此递推,得到任意阶数的多块排样方式的最大价值。通过比较块的排样价值的上界和下界来剔除不必要的多块划分,通过离散化划分线位置来控制算法的时间复杂度。采用文献典型例题和实际生产实例,将所提算法与一刀切排样算法和非一刀切排样算法进行对比,表明了所提算法的优越性。 展开更多
关键词 二维板材排样 递归多块排样方式 动态规划 排样价值 矩形件
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退耕还林还草工程对陕北地区生态系统服务的影响 被引量:3
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作者 安健吉 员学锋 +2 位作者 杨悦 安骐岷 苏强俊 《环境科学》 北大核心 2025年第4期2410-2427,共18页
以陕北地区为研究区域,量化评估生态系统固碳、产水、土壤保持和食物供给服务,判断退耕还林还草工程的实施区域和类型,从时空格局、热点分布和权衡与协同关系等方向综合分析退耕还林还草工程对陕北地区生态系统服务的影响.结果表明:①20... 以陕北地区为研究区域,量化评估生态系统固碳、产水、土壤保持和食物供给服务,判断退耕还林还草工程的实施区域和类型,从时空格局、热点分布和权衡与协同关系等方向综合分析退耕还林还草工程对陕北地区生态系统服务的影响.结果表明:①2000~2020年陕北地区生态系统碳储量、产水量、土壤保持量和食物产量分别增加0.19亿t(2.63%)、11.56亿m^(3)(51.35%)、3.44亿t(26.31%)和509.70万t(60.48%),退耕还林还草工程累计实施4538.25 km^(2),退耕还林区、退耕还草区和未利用地造林种草区分别占22.71%、73.46%和3.83%.②工程实施区内固碳和土壤保持服务的增幅较大,产水服务的增幅较小,食物供给服务呈下降趋势,不同类型工程实施区生态系统服务的变化情况存在明显的差异.③陕北地区多数生态系统服务间呈现权衡关系,2000~2020年间权衡关系逐渐减弱,工程实施区内的权衡关系相对更弱.④陕北地区能够同时提供多种生态系统服务的区域明显增加,退耕还林对增加多重热点区的促进效果明显,未利用地造林种草对消除0类热点区具有积极的作用.⑤未来,陕北地区应着力提升食物供给的可持续性并破除水资源短缺的瓶颈,可以结合生态系统服务的实际情况分类施策,通过未利用地造林种草减少生态系统服务匮乏的区域,通过间作套作和立体农业等方式促进多项生态系统服务的协同发展. 展开更多
关键词 生态系统服务 退耕还林还草工程 时空格局 热点分布 权衡与协同 陕北地区
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坏死性凋亡分子机制及与牙周炎的相关性
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作者 孙欢欢 赵菲 +1 位作者 陶然 刘冰 《中国组织工程研究》 CAS 北大核心 2025年第12期2569-2574,共6页
背景:近年来,随着细胞死亡研究的不断深入,坏死性凋亡逐渐成为学术界研究的热点和难点,其多种信号通路及蛋白在牙周炎的发生发展中起到不可忽视的作用,人们试图通过阻止细胞坏死性凋亡的发生,从而延缓牙周组织炎症的进程。目的:就坏死... 背景:近年来,随着细胞死亡研究的不断深入,坏死性凋亡逐渐成为学术界研究的热点和难点,其多种信号通路及蛋白在牙周炎的发生发展中起到不可忽视的作用,人们试图通过阻止细胞坏死性凋亡的发生,从而延缓牙周组织炎症的进程。目的:就坏死性凋亡的分子机制及其与牙周炎的相关性进行综述,期望为牙周炎的预防、诊断、治疗及预后提供新思路、新方向。方法:第一作者于2023年10月应用计算机检索PubMed、中国知网等数据库建库到2024年4月发表的相关文献,以“坏死性凋亡,细胞程序性死亡,牙周炎,牙周,免疫,炎症,受体相互作用蛋白激酶1,受体相互作用蛋白激酶3,混合系列蛋白激酶样结构域”为中文检索词;“necroptosis,programmed cell death,periodontitis,periodontal,immunity,inflammation,RIP1,RIP3,MLKL”为英文检索词,阅读每篇文献的文题、摘要、引言进行初步筛选,最终纳入56篇文献进行总结分析。结果与结论:①牙周炎的主要发病机制为牙周致病菌刺激机体,导致牙周微环境发生改变,打破原有免疫平衡并释放各种炎症因子,引发炎症反应造成牙周组织破坏,坏死性凋亡可以调控牙周组织免疫炎症反应,从而影响牙周炎的发生发展进程;②坏死性凋亡的发生与多种蛋白、信号通路及信号分子有关,已有动物实验证实了磷酸化混合系列蛋白激酶样结构域(pMLKL)的表达量与炎症程度有关,且在患有牙周炎小鼠的牙周组织中,RIP3和pMLKL高表达,通过阻断RIP3/MLKL通路,有利于减少牙周组织炎症、控制牙周炎的进展;③探究pMLKL是否可作为牙周炎的诊断指标,在牙周炎的预防、诊断及治疗上有很大价值。 展开更多
关键词 坏死性凋亡 牙周炎 炎症 免疫 细胞程序性死亡 损伤相关分子模式 MLKL RIP3
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图片模糊集的减法和除法算子研究
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作者 孟伟伟 郑婷婷 +1 位作者 刘钧歌 吴孝宇 《山东大学学报(理学版)》 北大核心 2025年第1期45-62,共18页
针对图片模糊环境下完备的减法和除法问题,构造加法和乘法的方程,定义了图片模糊数(picture fuzzy numbers,PFNs)的减法和除法运算。基于距离最近导出各种情形下方程的最优解,得出更加完备的PFNs的减法和除法运算法则。分析了2种PFNs算... 针对图片模糊环境下完备的减法和除法问题,构造加法和乘法的方程,定义了图片模糊数(picture fuzzy numbers,PFNs)的减法和除法运算。基于距离最近导出各种情形下方程的最优解,得出更加完备的PFNs的减法和除法运算法则。分析了2种PFNs算子及与加法、乘法混合运算的相关性质。将改进的2种算子以逐点的方式拓展到图片模糊集上,讨论了基本性质。通过算例分析验证该算子的适用性和可行性。 展开更多
关键词 图片模糊集 线性规划 减法算子 除法算子 模式识别
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球馆预约小程序的设计与实现
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作者 潘雨婷 丁勇 《福建电脑》 2025年第11期100-104,共5页
随着智能手机普及率超过90%,移动化趋势日益显著。针对传统球馆预约方式效率低、管理混乱的问题,开发球馆预约小程序具有重要现实意义。本文基于MVC设计模式,采用微信开发者工具、SpringBoot框架、MyBatis-Plus及MySQL数据库,设计并实... 随着智能手机普及率超过90%,移动化趋势日益显著。针对传统球馆预约方式效率低、管理混乱的问题,开发球馆预约小程序具有重要现实意义。本文基于MVC设计模式,采用微信开发者工具、SpringBoot框架、MyBatis-Plus及MySQL数据库,设计并实现了具备球馆信息查询、预约时段查看、在线预约、评价与反馈等功能的小程序。测试表明,该系统界面简洁、功能完善、操作便捷,能有效提升用户预约体验。 展开更多
关键词 球馆预约 微信小程序 MVC模式 SpringBoot框架
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日本JST战略性基础研究计划的组织模式及对我国的启示
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作者 刘云 武宇铎 +1 位作者 徐德英 尤宇 《世界科技研究与发展》 2025年第4期417-428,共12页
战略导向基础研究聚焦国家战略需求和科学前沿,通过有组织地部署开展重大基础研究,解决经济社会发展中的关键科学问题,为培育新质生产力提供源头支撑。然而,中国战略导向基础研究的组织体系尚不能完全适应高水平科技自立自强的需求,亟... 战略导向基础研究聚焦国家战略需求和科学前沿,通过有组织地部署开展重大基础研究,解决经济社会发展中的关键科学问题,为培育新质生产力提供源头支撑。然而,中国战略导向基础研究的组织体系尚不能完全适应高水平科技自立自强的需求,亟需借鉴发达国家的组织实施经验。21世纪以来,主要国家围绕战略性领域,瞄准前沿科技和产业领域,出台了一系列战略规划,加强战略导向基础研究的前瞻布局。其中,日本JST设立的战略性基础研究计划致力于在未来社会需求和国家战略领域,资助开展战略目标导向的高水平基础研究活动,已形成较为成熟的组织体系并孕育了多项重大原创性成果。本文首先研究JST“前沿突破导向型”和“应用螺旋推进型”两类战略性基础研究计划的战略定位及资助管理体系;之后,以CREST计划、ERATO计划、JST-Mirai未来计划为案例,对战略性基础研究计划组织实施层面的项目组织方式与资助规模、遴选和评估标准、资助成效进行深入剖析;最后,在分析中国战略导向基础研究组织体系现状及主要问题的基础上,从顶层设计、资助模式、评价体系、生态构建等方面提出对中国的政策启示。 展开更多
关键词 战略导向基础研究 JST战略性基础研究计划 科技计划 组织体系 国际经验
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时序图模式匹配的查询优化
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作者 覃紫云 郭青松 +3 位作者 马国帅 张凯涵 石琼 蔡江辉 《计算机系统应用》 2025年第11期42-55,共14页
图模拟被广泛应用于近似回答复杂的图模式匹配问题.针对时序图模式匹配的查询效率问题,本文提出一种基于联合图的SimAssign图模拟算法及动态规划的优化框架.其核心思想在于:(1)将时序图的快照序列合并为联合图,首先利用静态图模拟算法... 图模拟被广泛应用于近似回答复杂的图模式匹配问题.针对时序图模式匹配的查询效率问题,本文提出一种基于联合图的SimAssign图模拟算法及动态规划的优化框架.其核心思想在于:(1)将时序图的快照序列合并为联合图,首先利用静态图模拟算法在联合图上计算初始查询结果,然后根据时间区间将结果分发至每个快照,从而生成相应的匹配结果;(2)为图模拟策略构建统一的代价模型,并基于动态规划优化图模式匹配的执行策略.本文在真实数据集和合成数据集上进行了全面实验,实验结果表明代价模型能够准确估计静态图模拟、增量图模拟以及SimAssign等图模拟策略的执行代价,并且优化方法能够选择出最优的执行方案.在绝大多数情况下,SimAssign的性能显著优于静态图模拟和增量式图模拟算法,在部分实验中SimAssign的性能达到增量法的4倍. 展开更多
关键词 时序图 图模式匹配 图模拟 代价模型 动态规划
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人机协作编程学习的认知与行为模式研究——基于学习风格差异的分析
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作者 董伟 赵芳旋 +1 位作者 余能保 张权 《远程教育杂志》 北大核心 2025年第4期86-96,共11页
生成式人工智能(generative artificial intelligence,GenAI)在编程学习中的应用日益受到关注。然而,目前较少有实证研究基于学习风格差异对人机协作编程学习进行分析。为此,本研究构建了GenAI辅助下的编程学习模型,并据此开展实验,系... 生成式人工智能(generative artificial intelligence,GenAI)在编程学习中的应用日益受到关注。然而,目前较少有实证研究基于学习风格差异对人机协作编程学习进行分析。为此,本研究构建了GenAI辅助下的编程学习模型,并据此开展实验,系统采集与分析了学习者的学习风格数据与过程行为数据。研究结果显示:(1)与GenAI协作编程有助于显著提升学生的学习效果;(2)在人机协作过程中,学生的行为主要集中于独立编写代码与高级认知加工;(3)不同学习风格的学习者在编程过程中的认知模式与行为路径存在差异;(4)提问质量对GenAI反馈的准确性有一定影响。基于上述发现,本研究建议在实施人机协作编程学习中,教师应结合学习者的学习风格特征,设计个性化教学策略;同时,应高度重视对学生提问能力的培养,提升其利用GenAI工具进行编程学习的效率与深度,从而促进编程技能与综合素养的全面发展。 展开更多
关键词 生成式人工智能 人机协作 编程学习 学习风格 认知与行为模式
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2000-2020年民勤盆地植被净初级生产力时空变化特征及驱动因子
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作者 王怡璇 郝媛媛 +6 位作者 杨金顺 何生申 陈松清 刘雪霞 黄才成 孟哲 安春春 《草业科学》 北大核心 2025年第6期1391-1402,共12页
植被净初级生产力(NPP)变化是评估区域生态保护策略有效性的重要途径。本研究采用Landsat影像,利用改进型CASA模型和地理探测器,分析了2000-2020年(步长5年)民勤盆地植被NPP变化的时空特征,明确了植被NPP变化的主要驱动因子。结果表明:2... 植被净初级生产力(NPP)变化是评估区域生态保护策略有效性的重要途径。本研究采用Landsat影像,利用改进型CASA模型和地理探测器,分析了2000-2020年(步长5年)民勤盆地植被NPP变化的时空特征,明确了植被NPP变化的主要驱动因子。结果表明:2000-2020年民勤盆地植被NPP表现为先增加后降低,再增加态势,空间表现为绿洲区高、荒漠区低的格局;20年间民勤盆地植被NPP变化主要依赖于绿洲区,植被NPP显著增加(P<0.05)或极显著增加(P<0.01)主要集中于绿洲区乡镇居民区和农业生产区,而植被NPP显著减少或极显著减少主要集中于绿洲边缘和沙漠的过渡区。民勤盆地植被NPP变化的主导因子是土地利用和植被覆盖度,两者交互呈双因子增强效应,这为民勤盆地未来植被系统的合理管护提供了科学依据。 展开更多
关键词 植被净初级生产力 地理探测器 时空格局 石羊河流域综合治理工程 民勤盆地
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基于问题导向的软件构造课程教学方法探究
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作者 周芃 《高教学刊》 2025年第23期111-114,共4页
软件构造是软件工程专业一门重要的专业课,对学生软件开发的理论和实践有较高的要求。针对软件构造课程教学中面临的问题,如概念抽象、难度较大、学生不易掌握等,对软件构造教学方法进行研究。提出问题导向的教学方法,以具体项目切入,... 软件构造是软件工程专业一门重要的专业课,对学生软件开发的理论和实践有较高的要求。针对软件构造课程教学中面临的问题,如概念抽象、难度较大、学生不易掌握等,对软件构造教学方法进行研究。提出问题导向的教学方法,以具体项目切入,贯穿课程,在项目实现过程中,不断提出问题引导学生主动思考,探索解决方案,从而发现、掌握知识点。改革课程考核方案,加强过程考核,重点考察学生解决实际问题能力。结果表明,课程可以激发学生主动学习的兴趣,加强学生对知识点的掌握,使学生可以较好地融会贯通并灵活应用各知识点解决实际问题,提升学生工程能力。 展开更多
关键词 软件构造 设计模式 问题导向 教学方法研究 课程考核方案研究
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Cutting technic for Pinus elliottii plantation of the multi-benefit management pattern
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作者 王青春 孙海放 +1 位作者 吴从健 彭倚云 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期69-72,J003,共5页
The cutting technic for thePinus elliottii plantation of the multi-benefit management pattern in the hilly region of Jiangxi Province was studied by establishing the model of growth progress according to Richards func... The cutting technic for thePinus elliottii plantation of the multi-benefit management pattern in the hilly region of Jiangxi Province was studied by establishing the model of growth progress according to Richards function and simulating the tending cutting on computer by use of dynamic programming. The results showed that the best time for the initial thinning was at tree age of 8–10 and final cutting was at tree age of 25. The optimal thinning project was 3 times of thinning cutting including the first thinning, and the thinning time was at tree ages of 8, 12 and 16, respectively. Their thinning intensities were separately 950, 700 and 300 trunks per hectare, and the preserved density was 550 trunks per hectare until the final cutting Keywords Pinus elliottir - Multi-benefit management pattern - Richards function - Cutting technic - Dynamic programming CLC number S757.4 Document code A Foundation item: This study was supported by Natural Science Foundation of Jiangxi Province (A grant 0330023)Biography: WANG Qing-chun (1970-), male, Ph. Doctor, Senior Engineer in Academy of Forest Inventory & Planning, Jiangxi, Nanchang 330046, P.R. China.Responsible editor: Song Funan 展开更多
关键词 Pinus elliottir Multi-benefit management pattern Richards function Cutting technic Dynamic programming
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Visualization of flatness pattern recognition based on T-S cloud inference network 被引量:2
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作者 张秀玲 赵亮 +1 位作者 臧佳音 樊红敏 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期560-566,共7页
Flatness pattern recognition is the key of the flatness control. The accuracy of the present flatness pattern recognition is limited and the shape defects cannot be reflected intuitively. In order to improve it, a nov... Flatness pattern recognition is the key of the flatness control. The accuracy of the present flatness pattern recognition is limited and the shape defects cannot be reflected intuitively. In order to improve it, a novel method via T-S cloud inference network optimized by genetic algorithm(GA) is proposed. T-S cloud inference network is constructed with T-S fuzzy neural network and the cloud model. So, the rapid of fuzzy logic and the uncertainty of cloud model for processing data are both taken into account. What's more, GA possesses good parallel design structure and global optimization characteristics. Compared with the simulation recognition results of traditional BP Algorithm, GA is more accurate and effective. Moreover, virtual reality technology is introduced into the field of shape control by Lab VIEW, MATLAB mixed programming. And virtual flatness pattern recognition interface is designed.Therefore, the data of engineering analysis and the actual model are combined with each other, and the shape defects could be seen more lively and intuitively. 展开更多
关键词 pattern recognition T-S cloud inference network cloud model mixed programming virtual reality visual recognition
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Evaluation of prognostic factors and clinicopathological patterns of recurrence after curative surgery for colorectal cancer 被引量:1
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作者 Filippo Melli Ilenia Bartolini +5 位作者 Matteo Risaliti Rosaria Tucci Maria Novella Ringressi Paolo Muiesan Antonio Taddei Amedeo Amedei 《World Journal of Gastrointestinal Surgery》 SCIE 2021年第1期50-75,共26页
BACKGROUND Colorectal cancer is a common tumor with a quite high-related mortality.Despite the used curative treatments,patients will develop cancer recurrence in up to 50%of the cases and/or other primary neoplasms.A... BACKGROUND Colorectal cancer is a common tumor with a quite high-related mortality.Despite the used curative treatments,patients will develop cancer recurrence in up to 50%of the cases and/or other primary neoplasms.Although most of the recurrences are discovered within 3 years from the first treatment,a small percentage is found after 5 years.The early detection of recurrence is crucial to allow further therapies improving patients’survival.Several follow-up programs have been developed but the optimal one is far from being established.AIM To evaluation of potential prognostic factors for timing and patterns of recurrence in order to plan tailored follow-up programs.METHODS Perioperative and long-term data of all consecutive patients surgically treated with curative intent,from January 2006 to June 2009,for colorectal adenocarcinoma,were retrospectively reviewed to find potential prognostic factors associated with:(1)Recurrence incidence;(2)Incidence of an early(within 3 years from surgery)or late recurrence;and(3)Different sites of recurrence.In addition,the incidence of other primary neoplasms has been evaluated in a cohort of patients with a minimum potential follow-up of 10 years.RESULTS Our study included 234 patients.The median follow-up period has been 119±46.2 mo.The recurrence rate has been 25.6%.Patients with a higher chance to develop recurrence had also the following characteristics:Higher levels of preoperative glycemia and carcinoembryonic antigen,highest anaesthesiologists Score score,occlusion,received a complex operation performed with an open technique,after a longer hospital stay,and showed advanced tumors.The independent prognostic factors for recurrence were the hospital stay,N stage 2,and M stage 1(multivariate analysis).Younger ages were significantly associated with an early recurrence onset.Patients that received intermediate colectomies or segmental resections,having an N stage 2 or American Joint Committee on Cancer stage 3 tumors were also associated with a higher risk of liver recurrence,while metastatic diseases at diagnosis were linked with local recurrence.Neoadjuvant treatments showed lung recurrence.Finally,bigger tumors and higher lymph node ratio were associated with peritoneal recurrence(marginally significant).Thirty patients developed a second malignancy during the follow-up time.CONCLUSION Several prognostic factors should be considered for tailored follow-up programs,eventually,beyond 5 years from the first treatment. 展开更多
关键词 Prognostic factors RECURRENCE Recurrence patterns Colorectal cancer Longterm follow-up Follow-up programs
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Context-Aware Practice Problem Recommendation Using Learners’ Skill Level Navigation Patterns 被引量:1
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作者 P.N.Ramesh S.Kannimuthu 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3845-3860,共16页
The use of programming online judges(POJs)has risen dramatically in recent years,owing to the fact that the auto-evaluation of codes during practice motivates students to learn programming.Since POJs have greater numb... The use of programming online judges(POJs)has risen dramatically in recent years,owing to the fact that the auto-evaluation of codes during practice motivates students to learn programming.Since POJs have greater number of pro-gramming problems in their repository,learners experience information overload.Recommender systems are a common solution to information overload.Current recommender systems used in e-learning platforms are inadequate for POJ since recommendations should consider learners’current context,like learning goals and current skill level(topic knowledge and difficulty level).To overcome the issue,we propose a context-aware practice problem recommender system based on learners’skill level navigation patterns.Our system initially performs skill level navigation pattern mining to discover frequent skill level navigations in the POJ and tofind learners’learning goals.Collaborativefiltering(CF)and con-tent-basedfiltering approaches are employed to recommend problems in the cur-rent and next skill levels based on frequent skill level navigation patterns.The sequence similarity measure is used tofind the top k neighbors based on the sequence of problems solved by the learners.The experiment results based on the real-world POJ dataset show that our approach considering the learners’cur-rent skill level and learning goals outperforms the other approaches in practice problem recommender systems. 展开更多
关键词 Recommender systems skill level navigation pattern programming online judge collaborativefiltering content-basedfiltering
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Evolution Process of Urban Spatial Pattern in Hubei Province Based on DMSP/OLS Nighttime Light Data 被引量:4
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作者 ZHENG Wensheng RUN Jiying +2 位作者 ZHUO Rongrong JIANG Yupei WANG Xiaofang 《Chinese Geographical Science》 SCIE CSCD 2016年第3期366-376,共11页
This paper intends to investigate the urban spatial patterns of Hubei Province and its evolution from three different perspectives: urban nodes, urban connections and urban clusters. The research adopts nighttime ligh... This paper intends to investigate the urban spatial patterns of Hubei Province and its evolution from three different perspectives: urban nodes, urban connections and urban clusters. The research adopts nighttime light imagery of cities in Hubei Province, the viewpoint of ′point-axis-area′ in the ′point-axis system′ theory, and employs light index model, gravity model and social network analysis. The findings are as follows: 1) In terms of urban nodes, the urbanization process of Hubei has been carried out mainly on the basis of external expansion rather than internal increasing. The polarization trend of urban connection network is strengthening. 2) As for urban connections, the estimation of urban connections using light index model is capable of containing various actual flow, and the connections are getting increasingly closer. 3) In regard to urban groups, seven urban groups of varying sizes have formed. On that basis, three stable and relatively independent urban groups as the centers, namely Wuchang, Yichang and Xiangyang emerge as well. But the structures of ′Wuhan Metropolitan Area′, ′Yichang-Jingzhou-Jingmen City Group′ and ′Xiangyang-Shiyen-Suizhou City Group′, which are defined by local development strategy in Hubei Province, are different from the above three urban groups. 展开更多
关键词 Defence Meteorological Satellite program′s Operational Linescan System(DMSP/OLS) urban spatial pattern point-axis-area Hubei Province China
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