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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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基于多轴精雕系统的蜡模雕刻工艺
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作者 张余益 梁雄 +1 位作者 李睿 王龙兵 《中国现代教育装备》 2026年第3期56-59,63,共5页
本文主要研究基于多轴精雕系统来完成工业制造中蜡模的雕刻工艺。基于多轴精雕系统的蜡模雕刻对空天、科研、军事、精密器械、高端首饰、高精医疗设备等领域有非常大的影响和技术变革冲击。因此,对基于多轴精雕系统的蜡模雕刻工艺进行研... 本文主要研究基于多轴精雕系统来完成工业制造中蜡模的雕刻工艺。基于多轴精雕系统的蜡模雕刻对空天、科研、军事、精密器械、高端首饰、高精医疗设备等领域有非常大的影响和技术变革冲击。因此,对基于多轴精雕系统的蜡模雕刻工艺进行研究,并使其更好地应用在实践教学课程中让学生更深入地学习此技术很有必要。 展开更多
关键词 多轴精雕 蜡模制作 自动编程
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职业本科特色化就业育人模式的探索与实践
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作者 陈双艳 张昭 《语言与文化研究》 2026年第2期107-110,共4页
随着生态文明建设上升为国家战略和职业教育体系的不断发展,职业本科教育作为高等教育与职业教育的融合载体,成为培养高层次技术技能人才的重要途径。本文以生态环境工程技术专业为例,探索职业本科特色化就业育人模式。通过分析该专业... 随着生态文明建设上升为国家战略和职业教育体系的不断发展,职业本科教育作为高等教育与职业教育的融合载体,成为培养高层次技术技能人才的重要途径。本文以生态环境工程技术专业为例,探索职业本科特色化就业育人模式。通过分析该专业的人才需求特点、就业目标岗位以及当前就业育人存在的问题,阐述了从构建特色课程体系、强化实践教学体系、打造双师型教师队伍、开展精准就业指导与个性化职业规划等多方面构建特色化就业育人模式的策略与实践教学,旨在为职业本科院校提高人才培养质量、提升学生就业竞争力和实现高质量就业,培养出具有较强实践能力和创新精神的高层次技术技能人才,能够在生产、建设、管理、服务第一线从事专业技术工作的应用型人才,为职业教育的改革提供有益经验。 展开更多
关键词 职业本科 特色化 就业育人 模式 实践
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特厚急倾斜综放面采空区煤自燃分级预警体系构建与应用
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作者 吴军 潘博 +3 位作者 汪强 王冰山 曹琛 邓仕杰 《煤炭工程》 北大核心 2026年第1期108-115,共8页
采空区内煤自燃隐患的监测与预警,是预防煤自燃火灾的关键前置环节,也是当前矿井火灾防控领域亟待突破的核心技术难题。为解决赤城煤矿5^(-2)煤层1502^(-2)特厚急倾斜综放工作面回采期间的煤自燃监测预警难题,采用煤自燃程序升温实验,... 采空区内煤自燃隐患的监测与预警,是预防煤自燃火灾的关键前置环节,也是当前矿井火灾防控领域亟待突破的核心技术难题。为解决赤城煤矿5^(-2)煤层1502^(-2)特厚急倾斜综放工作面回采期间的煤自燃监测预警难题,采用煤自燃程序升温实验,系统揭示了测试煤样在不同温度下自燃氧化过程中,CO、CO_(2)、CH_(4)、C_(2)H_(6)、C_(2)H_(4)、C_(2)H_(2)等气体浓度随煤温的演化规律。结合现场实测数据,经指标优选确定了CO、C 2H 4为煤自燃预测核心指标气体,同时选取Δφ(CO)/Δφ(O 2)、φ(C_(2)H_(4))/φ(C_(2)H_(6))作为关键预警指标,构建了“灰、蓝、黄、橙、红”五级分级预警体系,并明确了各等级对应的现场预警阈值,形成适配该类工作面的煤自燃分级预警技术体系。该体系在5^(-2)煤层1502^(-2)综放工作面成功应用,实现了煤自燃隐患的早期预警,有效提升了矿井煤自燃火灾防控技术水平,为工作面安全高效回采提供了可靠保障。 展开更多
关键词 煤自燃 特厚急倾斜煤层 指标气体 格氏火灾系数 程序升温实验 漏风规律
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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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Study on Test Compaction in High-Level Automatic Test Pattern Generation (ATPG) Platform 被引量:1
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作者 Ayub Chin Abdullah Chia Yee Ooi 《Circuits and Systems》 2013年第4期342-349,共8页
Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic t... Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic test pattern generation (ATPG). In addition, ATPG needs to deal with new defects caused by process variation when IC is shrinking. To reduce the computation effort of ATPG, test generation could be started earlier at higher abstraction level, which is in line with top-down design methodology that has become more popular nowadays. In this research, we employ Chen’s high-level fault model in the high-level ATPG. Besides shorter ATPG time as shown in many previous works, our study showed that high-level ATPG also contributes to test compaction. This is because most of the high-level faults correlate with the gate-level collapsed faults especially at input/output of the modules in a circuit. The high-level ATPG prototype used in our work is mainly composed by constraint-driven test generation engine and fault simulation engine. Experimental result showed that more reduced/compact test set can be generated from the high-level ATPG. 展开更多
关键词 Automatic TEST pattern Generation (ATPG) Constraint Logic programming (CLP) Verilator Circuit-Under-Test (CUT) TEST COMPACTION
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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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Multi-View Feature Fusion Model for Software Bug Repair Pattern Prediction
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作者 XU Yong CHENG Ming 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第6期493-507,共15页
Many search-based Automatic Program Repair(APR)techniques employ a set of repair patterns to generate candidate patches.Regarding repair pattern selection,existing search-based APR techniques either randomly select a ... Many search-based Automatic Program Repair(APR)techniques employ a set of repair patterns to generate candidate patches.Regarding repair pattern selection,existing search-based APR techniques either randomly select a repair pattern from the repair pattern set to apply or prioritize all repair patterns based on the bug's context information.In this paper,we introduce PatternNet,a multi-view feature f usion model capable of predicting the repair pattern for a reported software bug.To accomplish this task,PatternNet first extracts multiview features from the pair of buggy code and bug report using different models.Specifically,a transformer-based model(i.e.,UniXcoder)is utilized to obtain the bimodal feature representation of the buggy code and bug report.Additionally,an Abstract Syntax Tree(AST)-based neural model(i.e.,ASTNN)is employed to learn the feature representation of the buggy code.Second,a co-attention mechanism is adopted to capture the dependencies between the statement trees in the AST of the buggy code and the textual tokens of the reported bug,resulting in co-attentive features between statement trees and reported bug's textual tokens.Finally,these multi-view features are combined i nto a unified representation using a feature fusion network.We quantitatively demonstrate the effectiveness of PatternNet and the feature fusion network for predicting software bug repair patterns. 展开更多
关键词 Automatic program Repair(APR) bug repair pattern prediction Recurrent Neural Network(RNN) transformer co-attention
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Propagation Pattern模型及改进
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作者 谢康林 杜晓峰 《计算机应用与软件》 CSCD 1996年第2期21-29,共9页
面向对象对软件工程有着极大的意义,但同时也带来了编程上的新问题。由于复杂类结构和冗余代码所带来的源码重读困难,使软件进化和维护都未达到理想的目的。我们研究美国Northeastern大学的自动面向对象程序生成工具Propagation Patter... 面向对象对软件工程有着极大的意义,但同时也带来了编程上的新问题。由于复杂类结构和冗余代码所带来的源码重读困难,使软件进化和维护都未达到理想的目的。我们研究美国Northeastern大学的自动面向对象程序生成工具Propagation Pattern模型,并将其发展为一种新的程序索引描述。这里我们结合类图和Propagation Pattern抽象描述,希望能以简洁的图文形式描述面向对象程序,以利于软件的重读和进化。 展开更多
关键词 面向对象 软件工程 PP模型
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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:2
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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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基于多近似一致性ADMM的阵列方向图合成
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作者 巩朋成 刘永康 +1 位作者 吴云韬 李利荣 《现代雷达》 北大核心 2025年第12期22-31,共10页
针对方向图合成中需指定主瓣和旁瓣电平的问题,提出了基于多近似优化和一致性交替方向乘子法(CADMM)的方向图合成方法。该方法在旁瓣和主瓣区域功率和的限制下,最小化了旁瓣最大功率与主瓣最小功率的比值。首先,引入辅助变量解耦合分子... 针对方向图合成中需指定主瓣和旁瓣电平的问题,提出了基于多近似优化和一致性交替方向乘子法(CADMM)的方向图合成方法。该方法在旁瓣和主瓣区域功率和的限制下,最小化了旁瓣最大功率与主瓣最小功率的比值。首先,引入辅助变量解耦合分子和分母并分隔成两个独立的子问题;接着,利用log-sum-exp近似方法将两个独立的子问题近似为具有统一形式的子问题,并采用两种近似算法对变形后的目标函数做了近似处理;最后,通过CADMM消除等式约束且迭代求解加权矢量,且在每次迭代中获得具体解。另外,文中也分析了算法的复杂度。实验结果表明该方法能得到较低旁瓣,且能很好地实现波束图合成,适用于任意一维线性阵列配置。文中研究为求解非凸和非线性化的分式规划问题和提高波束图合成算法性能提供了一种思路和途径。 展开更多
关键词 方向图综合 分式规划 多近似优化 交替方向乘子法
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编程任务中生成式人工智能工具对学习者自我效能感、认知模式和编程行为的影响研究
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作者 徐静 李泊文 +1 位作者 吴林静 高喻 《数字教育》 2025年第6期9-16,共8页
生成式人工智能技术拥有强大的代码生成功能,因此被广泛应用于各类编程任务。但是,生成式人工智能对学习者编程学习的影响尚不明确。该研究以某高校“计算思维”课程的学习者为研究对象,通过准实验研究的方式,探索在编程问题解决过程中... 生成式人工智能技术拥有强大的代码生成功能,因此被广泛应用于各类编程任务。但是,生成式人工智能对学习者编程学习的影响尚不明确。该研究以某高校“计算思维”课程的学习者为研究对象,通过准实验研究的方式,探索在编程问题解决过程中应用生成式人工智能工具对学习者的自我效能感、认知模式和编程行为的影响。实验结果显示:与生成式人工智能工具的交互并未显著增强学习者的自我效能感;学习者在问题解决过程中的认知加工模式更为单一;在行为模式上更加依赖“复制粘贴”类行为,而缺少“修改调试”类行为。基于上述结论,研究进一步提出相关建议:在应用生成式人工智能工具支持编程学习时,教师需要采用更为丰富的策略来提升学习者的编程自我效能感;尝试融合“人-人协作”与“人-机协作”来完成编程任务;引导学习者采用更为多样化的编程行为模式来进行代码编写。上述结论与建议对于运用人工智能技术支持编程学习具有重要的参考价值。 展开更多
关键词 生成式人工智能 编程学习 人机协作 认知模式 编程行为
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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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