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复合型人工湿地模型对污水厂尾水的深度净化效果 被引量:11
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作者 赵安娜 柯凡 +3 位作者 郭萧 冯慕华 潘继征 李文朝 《生态与农村环境学报》 CAS CSSCI CSCD 北大核心 2010年第6期579-585,共7页
采用由一级垂直流湿地、连续的4级沉水植物氧化塘和二级垂直流湿地组成的复合型人工湿地处理小城镇污水处理厂尾水。结果表明,在0.13 m3.m-2.d-1水力负荷条件下,模型出水仅ρ(CODCr)和ρ(氨氮)(以NH4+-N计)达到地表Ⅲ类水标准(GB 3838—... 采用由一级垂直流湿地、连续的4级沉水植物氧化塘和二级垂直流湿地组成的复合型人工湿地处理小城镇污水处理厂尾水。结果表明,在0.13 m3.m-2.d-1水力负荷条件下,模型出水仅ρ(CODCr)和ρ(氨氮)(以NH4+-N计)达到地表Ⅲ类水标准(GB 3838—2002);但当进水ρ(TP)达到《城镇污水处理厂污染物排放标准》(GB18918—2002)一级B标准时,出水ρ(TP)亦达到地表Ⅲ类水标准。当二级垂直流湿地水力负荷调整为0.06 m3.m-2.d-1时,出水ρ(TP)和ρ(TN)最终都达到地表Ⅲ类水标准。认为水体中TN主要通过一级垂直流湿地的过滤吸附和二级垂直流湿地的反硝化作用去除,而TP则主要以一级垂直流湿地中石灰石的吸附沉降方式来去除。 展开更多
关键词 复合型人工湿地模型 污水处理厂 尾水 深度处理 N P
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基于XML的复合型工程数据库管理系统模型 被引量:3
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作者 马智亮 朱小羽 《计算机工程与应用》 CSCD 北大核心 2002年第19期192-194,共3页
为了对工程应用中结构复杂、形式多样的数据进行管理,该文建立了将关系型数据库和XML技术结合在一起形成的复合型数据库管理系统模型。然后,介绍了笔者研制的基于该模型的数据库管理系统的原型系统XMLBase。
关键词 XML 复合型工程数据库管理系统模型 文档管理
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脆性岩石多裂纹扩展的复合型相场模型研究 被引量:2
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作者 赵晨臣 饶秋华 +1 位作者 易威 罗三 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2023年第2期565-575,共11页
针对现有基于拉/压、球/偏应变能分解的2种复合型相场模型间差异性及其适用范围缺乏比较研究等问题,采用交错算法,依托ABAQUS平台自编相场本构子程序UMAT和相场变量演化子程序HETVAL,建立2种复合型相场模型数值求解方法,模拟脆性岩石双... 针对现有基于拉/压、球/偏应变能分解的2种复合型相场模型间差异性及其适用范围缺乏比较研究等问题,采用交错算法,依托ABAQUS平台自编相场本构子程序UMAT和相场变量演化子程序HETVAL,建立2种复合型相场模型数值求解方法,模拟脆性岩石双裂纹渐进式扩展贯通过程并对比分析。通过开展不同中心平行间距下含双平行裂纹的红砂岩试件单轴压缩试验,比较验证2种复合型相场模型的有效性并阐明其异同性及适用范围。研究结果表明:随着中心间距的增加,双平行裂纹的起裂点位置、扩展方向(I型翼裂纹起裂,扩展方向近似垂直于原裂纹面)和二次萌生裂纹(Ⅱ型裂纹)扩展方向几乎不变,但二次萌生裂纹的位置从2个内尖端变为2个外尖端,且岩桥贯通轨迹从2组裂纹尖端间扩展贯通变成1组裂纹内尖端扩展贯通;2种复合型相场模型均能有效地模拟出Ⅰ型、Ⅱ型裂纹扩展,但基于球/偏应变能分解的复合型相场模型模拟的二次萌生裂纹扩展(Ⅱ型反翼裂纹,扩展方向与翼裂纹方向相反)和岩桥贯通轨迹(裂纹尖端翼裂纹直接相向扩展贯通)与试验结果更为吻合,更适合于复杂加载条件下的脆性岩石多裂纹扩展行为模拟。 展开更多
关键词 复合型相场模型 应变能分解 交错法 脆性岩石 裂纹扩展
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复合型催化模型在钩虫感染率变迁研究中的应用
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作者 廖清廉 王成科 《现代预防医学》 CAS 1996年第2期128-128,共1页
复合型催化模型在钩虫感染率变迁研究中的应用廖清廉王成科Muench.H在流行病学的催化模型一书中,介绍了催化模型的简单、可逆、两级3个基本型的原理、方法和应用[1]。此数学模型可概括一些传染病的年龄分布特征,通过测定... 复合型催化模型在钩虫感染率变迁研究中的应用廖清廉王成科Muench.H在流行病学的催化模型一书中,介绍了催化模型的简单、可逆、两级3个基本型的原理、方法和应用[1]。此数学模型可概括一些传染病的年龄分布特征,通过测定疾病在某地的“感染力”来了解疾病在... 展开更多
关键词 钩虫病 感染率 复合型催化模型
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复合型跨声速风洞AGARD-B标模设计与加工制造方法 被引量:1
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作者 杨党国 张征宇 +2 位作者 孙岩 王超 朱伟军 《实验流体力学》 EI CAS CSCD 北大核心 2010年第2期88-92,共5页
提出一种内部嵌套金属骨架/外部光敏树脂快速成型制造复合型跨声速风洞模型的方法,以AGARD-B标模为验证实例,介绍了复合型模型内部金属骨架与光敏树脂外形结构设计与加工制造方法,并完成了验证模型机翼金属骨架结构优化设计;对验证模型... 提出一种内部嵌套金属骨架/外部光敏树脂快速成型制造复合型跨声速风洞模型的方法,以AGARD-B标模为验证实例,介绍了复合型模型内部金属骨架与光敏树脂外形结构设计与加工制造方法,并完成了验证模型机翼金属骨架结构优化设计;对验证模型的强度、刚度校核与试验系统振动分析结果表明,在跨声速范围此方法基本可行。与金属模型相比,复合型模型减小了风洞模型重量,提高了模型-支撑系统固有频率,缩短了模型设计与加工周期。 展开更多
关键词 复合型模型 跨声速风洞 AGARD-B标模 设计与制造 光固化快速成型
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复合型催化模型在钩虫感染流行病学研究中的应用
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作者 钟金成 王成科 吕勇 《数理医药学杂志》 2003年第3期268-270,共3页
应用可逆与两级复合型催化模型拟合分析了某地区不同年龄钩虫感染率资料 ,并应用复合型催化模型拟合分析了潼南县、中江县、蓬溪县、南充县不同地区钩虫感染率资料 ,通过χ2 配合适度检验 ,结果表明拟合良好 ( P<0 .5 0 )
关键词 复合型催化模型 钩虫感染 流行病学 拟合优度 检验 钩虫病
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基于复合型BERT模型的文本检测及情感分析的校园反诈大数据综合平台开发
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作者 宋文哲 陈宇琪 +3 位作者 强宇韬 陆一凡 李馥娟 常正辉 《网络安全技术与应用》 2024年第5期61-65,共5页
当前,校园反诈问题日益严重,给学校和学生带来了巨大的安全隐患。传统的反诈手段和方法往往难以满足复杂多变的反诈需求。因此,开发一种基于大数据和人工智能技术的校园反诈综合平台具有重要的现实意义。本研究开发了基于复合型BERT模... 当前,校园反诈问题日益严重,给学校和学生带来了巨大的安全隐患。传统的反诈手段和方法往往难以满足复杂多变的反诈需求。因此,开发一种基于大数据和人工智能技术的校园反诈综合平台具有重要的现实意义。本研究开发了基于复合型BERT模型的校园反诈大数据综合平台,通过文本检测和情感分析等技术手段,提高校园反诈的准确性和效率。该平台采用了分层架构,包括前端展示层、业务逻辑层和数据存储层。其中,复合型BERT模型结合了BERT预训练模型、CNN和RNN,能够综合利用不同模型的优势,提取丰富的语义信息进行文本分类。BERT-BiLSTM-Att模型结合了BERT预训练模型、双向长短时记忆网络(BiLSTM)和注意力机制(Att),能有效实现情感分类。实验结果显示,改进模型的文本检测和情感分类方法能够有效检测诈骗信息和情感强度,与单一的BERT算法相比,在一定程度上降低了误报率,提高了准确率。通过这个平台,可以帮助学校和相关部门及时发现和应对反诈事件,提高校园的安全和秩序。然而,还需要进一步改进和优化平台的功能和性能,以满足校园反诈工作的需求。 展开更多
关键词 复合型BERT模型 校园反诈大数据综合平台 文本检测 情感分析
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拟自然群落在上海郊野公园应用模式的探析 被引量:6
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作者 冷寒冰 王红兵 《西北林学院学报》 CSCD 北大核心 2018年第4期254-260,共7页
郊野公园对改善城市生态环境、弥补城市绿地的不足起到积极作用,然而很多国内的郊野公园沿袭了城市公园模式,大量地表现为人工群落,缺少自然属性,无法实现群落的稳定性和可持续性,因此应引入拟自然群落模式。以上海为主,在实地调查和比... 郊野公园对改善城市生态环境、弥补城市绿地的不足起到积极作用,然而很多国内的郊野公园沿袭了城市公园模式,大量地表现为人工群落,缺少自然属性,无法实现群落的稳定性和可持续性,因此应引入拟自然群落模式。以上海为主,在实地调查和比较分析的基础上,提出了地带性复合型群落(ZMC)概念模型,即把地带性植物作为建群种,融合城市园艺植物资源,构建新的地带性-园艺植物混合模式,兼具群落稳定性和景观多样性。并举例说明了苦槠(Castanopsis sclerophylla)群落、青冈(Cyclobalanopsis glauca)群落、红楠(Machilus thunbergii)群落、冬青(Ilex chinensis)群落等拟自然群落模式。研究结果为未来的郊野公园设计提供了新的理念和群落模式。 展开更多
关键词 地带性植物 地带性复合型群落模型 建群种 乡土植物 城市园艺
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基于CRC法的无线通信系统在线误码率监测研究 被引量:1
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作者 孙宇轩 付兴烨 +1 位作者 李美丽 曹琦 《现代电子技术》 北大核心 2019年第16期94-97,103,共5页
针对传统误码监测方法未对通信节点分布情况进行分析,出现误码监测结果不佳及监测耗时长等问题,提出无线通信系统在线误码自动化监测方法。在相关工作分析的基础上,通过对通信系统进行前处理,结合处理所得通信数据,并将通信数据簇的发... 针对传统误码监测方法未对通信节点分布情况进行分析,出现误码监测结果不佳及监测耗时长等问题,提出无线通信系统在线误码自动化监测方法。在相关工作分析的基础上,通过对通信系统进行前处理,结合处理所得通信数据,并将通信数据簇的发生情况近似看作一个泊松过程,构建复合型泊松模型,得出误码分布结果。以此为依据,引入CRC方法计算丢失码与反转码数量,求解得出通信系统误码率,完成无线通信系统在线误码自动监测。实验结果表明,所提方法的通信数据采集质量较高,误码监测结果与实际情况基本一致,且监测耗时最长不超过10s,性能优越,为无线通信相关领域的发展提供了参考依据。 展开更多
关键词 无线通信系统 误码监测 复合型泊松模型 CRC 自动监测 前处理
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On the Training Modes of Interdisciplinary and Application-oriented Talents of Business English 被引量:3
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作者 郝钦海 《Sino-US English Teaching》 2006年第8期7-11,共5页
This paper focuses on the training modes of interdisciplinary and application-oriented talents of business English and the constructions of curriculum. In the light of our socialist market-oriented economy characteris... This paper focuses on the training modes of interdisciplinary and application-oriented talents of business English and the constructions of curriculum. In the light of our socialist market-oriented economy characteristics, the discussion proceeds, in theory and practice, by putting forward a relatively profound approach according to the trend in the demands for business English talents and to the operational patterns of business English discipline, with some suggestions about the training modes of interdisciplinary and application-oriented talents and the construction of curriculum. 展开更多
关键词 business English interdisciplinary and application-oriented talents training modes CURRICULUM
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Simulation of Land-use Scenarios for Beijing Using CLUE-S and Markov Composite Models 被引量:25
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作者 HU Yecui ZHENG Yunmei ZHENG Xinqi 《Chinese Geographical Science》 SCIE CSCD 2013年第1期92-100,共9页
This study investigated and simulated land use patterns in Beijing for the year 2000 and the year 2005 from the actual land use data for the year 1995 and the year 2000,respectively,by combining spatial land allocatio... This study investigated and simulated land use patterns in Beijing for the year 2000 and the year 2005 from the actual land use data for the year 1995 and the year 2000,respectively,by combining spatial land allocation simulation using the CLUE-S model,and numerical land demand prediction using the Markov model.The simulations for 2000 and 2005 were confirmed to be generally accurate using Kappa indices.Then the land-use scenarios for Beijing in 2015 were simulated assuming two modes of development:1) urban development following existing trends;and 2) under a strict farmland control.The simulations suggested that under either mode,urbanized areas would expand at the expense of land for other uses.This expansion was predicted to dominate the land-use conversions between 2005 and 2015,and was expected to be accompanied by an extensive loss of farmland.The key susceptible to land-use changes were found to be located at the central urban Beijing and the surrounding regions including Yanqing County,Changping District and Fangshan District.Also,the simulations predicted a considerable expansion of urban/suburban areas in the mountainous regions of Beijing,suggesting a need for priority monitoring and protection. 展开更多
关键词 CLUE-S model land use Markov model scenario simulation BEIJING
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Predicting Complex Word Emotions and Topics through a Hierarchical Bayesian Network 被引量:2
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作者 Kang Xin Ren Fuji 《China Communications》 SCIE CSCD 2012年第3期99-109,共11页
In this paper, we provide a Word Emotion Topic (WET) model to predict the complex word e- motion information from text, and discover the dis- trbution of emotions among different topics. A complex emotion is defined... In this paper, we provide a Word Emotion Topic (WET) model to predict the complex word e- motion information from text, and discover the dis- trbution of emotions among different topics. A complex emotion is defined as the combination of one or more singular emotions from following 8 basic emotion categories: joy, love, expectation, sur- prise, anxiety, sorrow, anger and hate. We use a hi- erarchical Bayesian network to model the emotions and topics in the text. Both the complex emotions and topics are drawn from raw texts, without con- sidering any complicated language features. Our ex- periment shows promising results of word emotion prediction, which outperforms the traditional parsing methods such as the Hidden Markov Model and the Conditional Random Fields(CRFs) on raw text. We also explore the topic distribution by examining the emotion topic variation in an emotion topic diagram. 展开更多
关键词 word emotion classification complex e-motion emotion intensity prediction emotion-topicvariation hierarchical Bayesian network
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A Composite Model Predictive Control Strategy for Furnaces
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作者 臧灏 李宏光 +1 位作者 黄静雯 王佳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期788-794,共7页
Tube furnaces are essential and primary energy intensive facilities in petrochemical plants. Operational optimization of furnaces could not only help to improve product quality but also benefit to reduce energy consum... Tube furnaces are essential and primary energy intensive facilities in petrochemical plants. Operational optimization of furnaces could not only help to improve product quality but also benefit to reduce energy consumption and exhaust emission. Inspired by this idea, this paper presents a composite model predictive control(CMPC)strategy, which, taking advantage of distributed model predictive control architectures, combines tracking nonlinear model predictive control and economic nonlinear model predictive control metrics to keep process running smoothly and optimize operational conditions. The controllers connected with two kinds of communication networks are easy to organize and maintain, and stable to process interferences. A fast solution algorithm combining interior point solvers and Newton's method is accommodated to the CMPC realization, with reasonable CPU computing time and suitable online applications. Simulation for industrial case demonstrates that the proposed approach can ensure stable operations of furnaces, improve heat efficiency, and reduce the emission effectively. 展开更多
关键词 FURNACE Tracking nonlinear model predictive control Economic nonlinear model predictive control Distributed model predictive control
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A Novel Method for the Fabrication of Granular Hydroxyapatite-bentonite Composite Adsorbents for the Removal of Pb2+ from an Aqueous Solution
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作者 ThiMinh Hieu Do Pham ThanhThao Tran AnhKhoaTon Minh Vien Le 《Journal of Environmental Science and Engineering(B)》 2016年第7期371-378,共8页
Granular HApB composite adsorbents, with dimensions of 4 mm × 4 mm, were prepared for the removal of lead from an aqueous solution. The effectiveness of the composites for Pb2+ removal from an aqueous solution w... Granular HApB composite adsorbents, with dimensions of 4 mm × 4 mm, were prepared for the removal of lead from an aqueous solution. The effectiveness of the composites for Pb2+ removal from an aqueous solution with different initial concentrations, adsorbent doses and reaction times were examined. The Langmuir isotherms, Freundlich isotherm models and pseudo-second order kinetic model were used in this analysis. It was found that the Langmuir model fitted the experimental data better than the Freundlich model, with a maximum adsorption capacity of 93.37 mg.g-1. The pseudo-second order kinetic model also fit the experiment data well with an adsorption capacity of 70.73 mg.g-1 after being reused for 3 times. Furthermore, the composites may possibly be used in processes for industrial water treatment. 展开更多
关键词 Environment AFFORESTATION poplar plantations timber marketing.
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Photon-Induced Production of Mirror Quarks from LHT Model at LHC
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作者 YUE Chong-Xing LIU Jin-Yan DING Li LIU Wei MA Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1041-1048,共8页
The photon-induced processes at the LHC provide clean experimental conditions due to absence of theproton remnants,which might produce complementary and interesting results for tests of the standard model and forsearc... The photon-induced processes at the LHC provide clean experimental conditions due to absence of theproton remnants,which might produce complementary and interesting results for tests of the standard model and forsearching of new physics.In the context of the littlest Higgs model with T-parity,we consider the photon-inducedproduction of the mirror quarks at the LHC.The cross sections for various production channels are calculated and asimply phenomenological analysis is performed by assuming leptonic decays. 展开更多
关键词 the mirror fermions the LHT model the LHC
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THE COMPOUND BINOMIAL MODEL WITH A CONSTANT DIVIDEND BARRIER AND PERIODICALLY PAID DIVIDENDS 被引量:4
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作者 Jiyang TAN Xiangqun YANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第1期167-177,共11页
Consider the compound binomial risk model with interest on the surplus under a constant dividend barrier and periodically paying dividends. A system of integral equations for the arbitrary moments of the sum of the di... Consider the compound binomial risk model with interest on the surplus under a constant dividend barrier and periodically paying dividends. A system of integral equations for the arbitrary moments of the sum of the discounted dividend payments until ruin is derived. Moreover, under a very relaxed condition, the solutions for arbitrary moments are obtained by setting up iteration processes because of a special property of the system of integral equations. 展开更多
关键词 Compound binomial risk model constant dividend barrier dividend period expected discounted dividends.
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Generation of isogenic single and multiplex gene knockout mice by base editing-induced STOP 被引量:3
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作者 Guang Yang Tianyu Zhu +9 位作者 Zongyang Lu Guanglei Li Hao Zhang Songjie Feng Yajing Liu Jianan Li Yu Zhang Jia Chen Xuejiang Guo Xingxu Huang 《Science Bulletin》 SCIE EI CSCD 2018年第17期1101-1107,共7页
Although CRISPR/Cas9 has been widely used to generate knockout mice, two major limitations remain:the founders usually carry a mixture of genotypes, and mosaicism harboring multiple genotypes.Therefore, it takes a lon... Although CRISPR/Cas9 has been widely used to generate knockout mice, two major limitations remain:the founders usually carry a mixture of genotypes, and mosaicism harboring multiple genotypes.Therefore, it takes a long time to get homozygous mutants. Recently developed base editing(BE) system,which introduces C-to-T conversion without double strand DNA cleavage, has been used to introduce artificial stop codons(i-STOP) to prematurely terminate translation, providing a cleaner strategy for genome engineering. Using this strategy, we generated CD160 KO and VISTA/CD160 double KO mice by microinjection of a single sg RNA targeting CD160 and a mixture of sg RNAs targeting VISTA and CD160,respectively. The BE system induced STOP efficiently in mouse embryos and consequently in founder mice without detectable off-target. Most interestingly, the majority of the mutants harbor same genetic modifications, indicating we generated isogenic single and multiplex gene mutant mice by BE-induced STOP. We also obtained homozygous mutant mouse in F1 mice, demonstrating the accelerated strategy in generating animal models. 展开更多
关键词 Base editing i-STOP isogenic KNOCKOUT VISTA CDI60
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A Markov decision problem in a risk model with interest rate and Markovian environment 被引量:2
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作者 TAN JiYang YANG XiangQun +1 位作者 LI ZiQiang CHENG YangJin 《Science China Mathematics》 SCIE CSCD 2016年第1期191-204,共14页
We consider the compound binomial model in a Markovian environment presented by Cossette et al.(2004). We modify the model via assuming that the company receives interest on the surplus and a positive real-valued prem... We consider the compound binomial model in a Markovian environment presented by Cossette et al.(2004). We modify the model via assuming that the company receives interest on the surplus and a positive real-valued premium per unit time, and introducing a control strategy of periodic dividend payments. A Markov decision problem arises and the control objective is to maximize the cumulative expected discounted dividends paid to the shareholders until ruin minus a discounted penalty for ruin. We show that under the absence of a ceiling of dividend rates the optimal strategy is a conditional band strategy given the current state of the environment process. Under the presence of a ceiling for dividend rates, the character of the optimal control strategy is given. In addition, we offer an algorithm for the optimal strategy and the optimal value function.Numerical results are provided to illustrate the algorithm and the impact of the penalty. 展开更多
关键词 Markovian environment optimal control strategy periodic dividend interest rate penalty for
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