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Approximative Method of Fixed Point for Φ-Pseudocontractive Operator and an Application to Equation with Accretive Operator
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作者 Yixin Wen Aifang Feng Yuguang Xu 《Journal of Applied Mathematics and Physics》 2014年第1期21-25,共5页
In this paper, Φ-pseudo-contractive operators and Φ-accretive operators, more general than the strongly pseudo-contractive operators and strongly accretive operators, are introduced. By setting up a new inequality, ... In this paper, Φ-pseudo-contractive operators and Φ-accretive operators, more general than the strongly pseudo-contractive operators and strongly accretive operators, are introduced. By setting up a new inequality, authors proved that if ?is a uniformly continuous Φ-pseudo-contractive operator then T has unique fixed point q and the Mann iterative sequence with random errors approximates to q. As an application, the iterative solution of nonlinear equation with Φ-accretive operator is obtained. The results presented in this paper improve and generalize some corresponding results in recent literature. 展开更多
关键词 DUALITY Mapping Φ-Pseudo-contractive operator Φ-Accretive operator MANN ITERATIVE Sequence with Random Error Terms
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Fractals Generated by Statistical Contraction Operators
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作者 Hu Di\|he School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期274-280,共7页
In the theory of random fractal, there are two important classes of random sets, one is the class of fractals generated by the paths of stochastic processes and another one is the class of factals generated by statist... In the theory of random fractal, there are two important classes of random sets, one is the class of fractals generated by the paths of stochastic processes and another one is the class of factals generated by statistical contraction operators. Now we will introduce some things about the probability basis and fractal properties of fractals in the last class. The probability basis contains (1) the convergence and measurability of a random recursive setK(ω) as a random element, (2) martingals property. The fractal properties include (3) the character of various similarity, (4) the separability property, (5) the support and zero-one law of distributionP k =P·K ?1, (6) the Hausdorff dimension and Hausdorff exact measure function. 展开更多
关键词 statistical contraction operator FRACTAL statistically self-similar set a. s. self-similar set
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Dissipative Properties of ω-Order Preserving Partial Contraction Mapping in Semigroup of Linear Operator
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作者 Akinola Yussuff Akinyele Kamilu Rauf +1 位作者 Aasa Moses Adebowale Omosowon Jude Babatunde 《Advances in Pure Mathematics》 2019年第6期544-550,共7页
This paper consists of dissipative properties and results of dissipation on infinitesimal generator of a C0-semigroup of ω-order preserving partial contraction mapping (ω-OCPn) in semigroup of linear operator. The p... This paper consists of dissipative properties and results of dissipation on infinitesimal generator of a C0-semigroup of ω-order preserving partial contraction mapping (ω-OCPn) in semigroup of linear operator. The purpose of this paper is to establish some dissipative properties on ω-OCPn which have been obtained in the various theorems (research results) and were proved. 展开更多
关键词 SEMIGROUP Linear operator DISSIPATIVE operator contractION Mapping and RESOLVENT
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Topological degree for 1-set-contractive fields in M-PN spaces and its applications 被引量:7
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作者 WU Zhao-qi ZHU Chuan-xi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第4期463-474,共12页
In this paper, we define the topological degree for 1-set-contractive fields in PN spaces. Based on this, we obtain some new fixed point theorems for 1-set-contractive operators. As an application, we study the existe... In this paper, we define the topological degree for 1-set-contractive fields in PN spaces. Based on this, we obtain some new fixed point theorems for 1-set-contractive operators. As an application, we study the existence of solutions for a kind of nonlinear Volterra integral equations in Z-M-PN space. 展开更多
关键词 PN-space 1-set-contractive operator topological degree fixed point theorem.
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MEAN VALUE OF ANALYTIC OPERATOR FUNCTIONS
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作者 喻小培 蹇明 《Acta Mathematica Scientia》 SCIE CSCD 1995年第4期468-473,共6页
In this paper, it is proved that if A is a normal proper contraction on Hilbert space H and F(z) = U(z) + iV(z) is operator-valued analytic on the unit disc Delta and 0 < p < 1, then parallel to F(A)parallel to(... In this paper, it is proved that if A is a normal proper contraction on Hilbert space H and F(z) = U(z) + iV(z) is operator-valued analytic on the unit disc Delta and 0 < p < 1, then parallel to F(A)parallel to(p) less than or equal to parallel to F(0)parallel to(p) + C-p (1 - parallel to A parallel to)(-2) [GRAPHICS] 展开更多
关键词 Hilbert space operator operator-valued function proper contraction
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HARNACK'S INEQUALITIES FOR ANALYTIC OPERATOR FUNCTIONS
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作者 蹇明 杨长森 《Acta Mathematica Scientia》 SCIE CSCD 1997年第4期437-442,共6页
Some Harnack type inequalities for analytic operator functions have been obtained in this paper.
关键词 operator proper contraction Harnack's Inequality Schwarz's lemma
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CARATHEODORY INEQUALITY FOR ANALYTIC OPERATOR FUNCTION
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作者 Yang Changsenof Math., Henan Normal Univ., Xinxiang 453002. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第3期285-289,共5页
Suppose H is a complex Hilbert space, A H(Δ) denotes the set of all analytic operator functions on Δ, and the set N H(Δ)={f(z)|f(z) is an analytic operator function on the open uint disk Δ, f(z)f(w)=f(w)f(z),f... Suppose H is a complex Hilbert space, A H(Δ) denotes the set of all analytic operator functions on Δ, and the set N H(Δ)={f(z)|f(z) is an analytic operator function on the open uint disk Δ, f(z)f(w)=f(w)f(z),f *(z)f(z)=f(z)f *(z),z,w∈Δ}. The note proves that if f(z)∈N H(Δ),(or A H(Δ))‖f(z)‖≤1,z∈Δ then‖f′(T)‖≤(1-‖T‖ 2) -1 ‖I-f *(T)f(T)‖ 12 ‖I-f(T)f *(T)‖ 12 , where T∈L(H)(orT *T=TT *,respectively),‖T‖<1,Tf=fT. 展开更多
关键词 Analytic operator function proper contraction resolution of identity.
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Some Result of Stability and Spectra Properties on Semigroup of Linear Operator
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作者 Kamilu Rauf Akinola Yussuff Akinyele +2 位作者 Mfon Okon Etuk Rafiu Obashola Zubair Moses Adebowale Aasa 《Advances in Pure Mathematics》 2019年第1期43-51,共9页
This paper consists of some properties of a new subclass of semigroup of linear operator. The stability and spectra analysis of ω-order preserving partial contraction mapping (ω-OCPn) are obtained. The results show ... This paper consists of some properties of a new subclass of semigroup of linear operator. The stability and spectra analysis of ω-order preserving partial contraction mapping (ω-OCPn) are obtained. The results show that operators on the proposed ω-OCPn are densely defined and closed. Several existing results in the literature are contained in this work. 展开更多
关键词 contractION Mapping SEMIGROUP BANACH Space RESOLVENT and BOUNDED operator
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Case Study:Productive Performance and Prediction of Operating Income of Small-Scale Contract Farming of Swine in Lampang,Thailand
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作者 Suntorn Wittayakun Worawut Chainetr +3 位作者 Nirundorn Kongngoen Weera Innaree Piyamas Tancharoenrat Ir.Marjuki 《Journal of Agricultural Science and Technology(A)》 2019年第3期177-181,共5页
The objective of this study was to examine productive performance and predict factors affecting operating income of small-scale contract farming of swine(SCFS)in Lampang,Thailand.Ten SCFSs were selected by purposive s... The objective of this study was to examine productive performance and predict factors affecting operating income of small-scale contract farming of swine(SCFS)in Lampang,Thailand.Ten SCFSs were selected by purposive sampling as primary data sources for two consecutive fattening cycles during the year 2015-2017.Data indicated that the SCFS was feeder pig finishing system which herd size(HS)averaged 502 head/farm.The animals consumed approximate 1.59 kg of feed/head/d.The average daily gain(ADG)was 675.22 g/d and feed conversion ratio(FCR)was 2.42.The mean of fattening time(FT)averaged 158 d/cycle.The culling rate(CR)and mortality rate(MR)were 0.17%and 2.50%,respectively.The predicted operating income(POI)was estimated by multiple linear regressions.The equation was:POI=2,700.912+0.027HS–7.119CR–18.225MR+16.885ABW+806.466FI–4.142ADG–420.281FCR–9.719FT(ABW=average body weight;FI=feed intake)with r=0.899,r2=0.808,p-value=0.009.According to stepwise procedure,the potential equation was:POI=323.664FI–9.769MR–22.635 with r=0.837,r2=0.701,p-value=0.000.This predicted equation would benefit as a monitoring index for SCFS to manage their expected operating income and proper farm management to be further profitable and sustainable. 展开更多
关键词 contract FARMING SWINE operating INCOME
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DIFFERENTIAL INEQUALITIES OF OPERATOR-VALUED ANALYTIC FUNCTIONS
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作者 蹇明 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期166-170,共5页
Some differential inequalities and integral inequalities for operator-valued an- alytic functions are investigated.
关键词 Proper contraction operator-valued analytic function differential inequality integral inequality
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Operator Equation and Application of Variation Iterative Method
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作者 Ning Chen Jiqian Chen 《Applied Mathematics》 2012年第8期857-863,共7页
In this paper, we study some semi-closed 1-set-contractive operators A and investigate the boundary conditions under which the topological degrees of 1-set contractive fields, deg (I-A, Ω, p) are equal to 1. Correspo... In this paper, we study some semi-closed 1-set-contractive operators A and investigate the boundary conditions under which the topological degrees of 1-set contractive fields, deg (I-A, Ω, p) are equal to 1. Correspondingly, we can obtain some new fixed point theorems for 1-set-contractive operators which extend and improve many famous theorems such as the Leray-Schauder theorem, and operator equation, etc. Lemma 2.1 generalizes the famous theorem. The calculation of topological degrees and index are important things, which combine the existence of solution of for integration and differential equation and or approximation by iteration technique. So, we apply the effective modification of He’s variation iteration method to solve some nonlinear and linear equations are proceed to examine some a class of integral-differential equations, to illustrate the effectiveness and convenience of this method. 展开更多
关键词 Topology DEGREES and Index 1-Set-contract operators Modified VARIATION ITERATION Method Integral-Differential Equation
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Region Analysis Approach for Constructing Solutions of Nonlinear Operator Equations(Dedicated to Professor You Zhaoyong for his 60th brithday)
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作者 M.A.Wolfe 《工程数学学报》 CSCD 1991年第2期31-45,共15页
Based on a variety of geometric observations for location of solutions, a general and unified region analysis framework for developing constructive solvability of nonlinear operator equations are proposed. Within this... Based on a variety of geometric observations for location of solutions, a general and unified region analysis framework for developing constructive solvability of nonlinear operator equations are proposed. Within this framework, the methods including interval, ball and ellipsoid methods can be studied in a unified way. The ball algorithm, as a typical example, is in particular analysed. 展开更多
关键词 Geometric ESTIMATOR ball ALGORITHM REGION contractION ALGORITHM computable test for existence of solution special types of nonlinear operators
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非正式治理的制度化运作:管区制与乡镇治理现代化的路径选择 被引量:1
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作者 袁明宝 《西南大学学报(社会科学版)》 CSSCI 北大核心 2024年第1期79-88,共10页
管区作为一种非正式的组织设置,在乡镇与村级治理单元之间建构出实体性质的中间结构,具有低成本、非正式性和制度稳定性等特点,成为乡镇政权的延伸。管区设置虽然增加了乡镇内部的“委托—代理”层级,但通过行政体制上的形式化设置和实... 管区作为一种非正式的组织设置,在乡镇与村级治理单元之间建构出实体性质的中间结构,具有低成本、非正式性和制度稳定性等特点,成为乡镇政权的延伸。管区设置虽然增加了乡镇内部的“委托—代理”层级,但通过行政体制上的形式化设置和实践中的非正式运作,具有了超越科层体制约束的优势,借助激励动员和组织重构实现了有效治理。管区借助乡镇内部人力资源的重新配置,在不变体制的情况下进行机制创新,实现了非正式治理的制度化运作,匹配了当前乡村社会转型和治理转型的需求,成为当前强国家治理背景下探索乡镇治理现代化的一条可行路径。 展开更多
关键词 管区制 非正式治理 准行政组织 制度化运作 行政发包 乡镇治理现代化
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集体经营性建设用地入市的规范路径研究——以入市合同的性质与效力为切入点 被引量:3
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作者 杨芳 陈燚 《南海学刊》 2024年第2期116-126,共11页
集体经营性建设用地的入市流转需要衔接以《土地管理法》为代表的公法规范和以《民法典》为代表的私法规范。集体经营性建设用地入市参照适用国有建设用地流转制度的同时,仍需关注集体经营性建设用地入市交易的特殊性。集体经营性建设... 集体经营性建设用地的入市流转需要衔接以《土地管理法》为代表的公法规范和以《民法典》为代表的私法规范。集体经营性建设用地入市参照适用国有建设用地流转制度的同时,仍需关注集体经营性建设用地入市交易的特殊性。集体经营性建设用地入市牵涉多方面法律关系,入市过程伴随着一系列新型且复杂的法律关系与权利义务发生,需要厘清农村集体经济组织的主体资格及权责边界,以规范农村集体经营性建设用地入市的主体范畴。同时通过规范集体经营性建设用地入市的土地用途,形成与国有建设用地相协调的统一城乡土地交易市场体系,进而对出让合同和租赁合同的性质与效力重新认定,构建符合自身特性的入市合同规范。 展开更多
关键词 集体经营性建设用地 入市土地用途 出让合同 租赁合同
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从经营方式演化看中国农业现代化的前沿问题
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作者 耿明斋 耿娜 《河南社会科学》 CSSCI 北大核心 2024年第5期65-73,共9页
在对家庭联产承包责任制改革确立农户主体地位及土地流转和规模化过程进行梳理的基础上,研究了正在蓬勃发展的几种有代表性的农业组织形式的特点和现代农业演化趋势,针对租佃高成本、超大规模垄断性经营和政府补贴等方面的问题,提出了... 在对家庭联产承包责任制改革确立农户主体地位及土地流转和规模化过程进行梳理的基础上,研究了正在蓬勃发展的几种有代表性的农业组织形式的特点和现代农业演化趋势,针对租佃高成本、超大规模垄断性经营和政府补贴等方面的问题,提出了相应的政策建议。 展开更多
关键词 土地流转 农业现代化 家庭规模经营 承包权长期化
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政府补贴下考虑风险厌恶的双渠道绿色供应链运营决策及协调契约
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作者 张涑贤 李悦 《物流技术》 2024年第4期72-88,共17页
在政府对绿色产品提供补贴的基础上,构建以制造商为主导的供应链博弈模型,利用均值方差法分析了在双方风险中性(RN)、双方风险厌恶(RA)、仅制造商风险厌恶(MRA)和仅零售商风险厌恶(RRA)4种模式下的双渠道绿色供应链决策及效用,并设计带... 在政府对绿色产品提供补贴的基础上,构建以制造商为主导的供应链博弈模型,利用均值方差法分析了在双方风险中性(RN)、双方风险厌恶(RA)、仅制造商风险厌恶(MRA)和仅零售商风险厌恶(RRA)4种模式下的双渠道绿色供应链决策及效用,并设计带有转移支付的成本分担契约以实现协调。研究发现:在RRA模式下,产品绿色度与风险厌恶程度正相关;而在MRA模式和RA模式下,产品绿色度与风险厌恶程度负相关;双方效用在4种模式下均与政府补贴正相关,且在RRA模式下制造商效用受政府补贴的影响最为显著;当研发成本系数较大时,在MRA模式和RRA模式下,一方的效用与另一方的风险厌恶程度正相关,而在RA模式下双方效用与风险厌恶程度负相关。此外,通过数值分析揭示了成本分担比例与风险厌恶程度负相关、与政府补贴正相关。以上结论可为双渠道绿色供应链的决策制定及协调管理提供参考。 展开更多
关键词 风险厌恶 政府补贴 双渠道绿色供应链 运营决策 协调契约
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基于多变量模式分析的飞行学员脑功能连接的识别研究
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作者 叶露 刘孟轩 +2 位作者 闫东峰 陈曦 马姗 《磁共振成像》 CAS CSCD 北大核心 2024年第2期108-114,共7页
目的基于多变量模式分析(multivariate pattern analysis,MVPA)对飞行学员和健康的普通人的大脑功能连接进行有效识别。材料与方法采集了40名已经取得执照的飞行专业在校学生与39名地面专业在校学生的功能磁共振数据。通过网络功能连接... 目的基于多变量模式分析(multivariate pattern analysis,MVPA)对飞行学员和健康的普通人的大脑功能连接进行有效识别。材料与方法采集了40名已经取得执照的飞行专业在校学生与39名地面专业在校学生的功能磁共振数据。通过网络功能连接分析得到功能连接矩阵作为特征,分别通过最小绝对收缩选择算子(least absolute shrinkage and selection operator,LASSO)算法与独立样本t检验方法对特征降维。使用不同核函数的支持向量机(support vector machine,SVM)进行训练和预测,使用留一交叉验证法进行模型性能评估,最终根据训练后SVM模型中的权重定位对应脑区之间的功能连接。结果使用LASSO特征筛选的线性(linear)核SVM模型准确率为81.82%,敏感度82.05%,特异度81.58%,曲线下面积(area under the curve,AUC)为0.88。核函数对模型准确率的影响不大。模型中右侧中央旁小叶、双侧中央后回、双侧顶下缘角回、右侧梭状回、左侧眶部额中回、左侧顶上回、右侧眶部额下回有较高的权重,模型中的权重集中在感觉运动网络(somatomotor network,SMN)与默认模式网络(default mode network,DMN),分别占用所有权重的25.62%和25.27%。结论结合LASSO算法进行特征筛选的SVM可以对飞行学员大脑进行有效识别,并且有更好的可解释性和更小的过拟合。模型权重信息反映了飞行学员主要在运动能力和感知能力有别于普通人。 展开更多
关键词 飞行学员 磁共振成像 功能连接 最小绝对收缩选择算子 支持向量机
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激发粮农增收活力:订单模式运作机制的多案例扎根分析
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作者 李福夺 尹昌斌 《农业经济与管理》 CSSCI 北大核心 2024年第4期1-12,共12页
立足新发展阶段,探索契约农业运作机制对推动小农户与现代农业有机衔接、促进农民增收和农业现代化转型具有重要意义。选取典型水稻主产区作为案例样本点,运用扎根理论质性分析法,借助Nvivo12 Plus对水稻企业、合作社等产业组织进行多... 立足新发展阶段,探索契约农业运作机制对推动小农户与现代农业有机衔接、促进农民增收和农业现代化转型具有重要意义。选取典型水稻主产区作为案例样本点,运用扎根理论质性分析法,借助Nvivo12 Plus对水稻企业、合作社等产业组织进行多案例分析,研究新发展理念下水稻订单模式的运作机制及其对农户增收的影响。研究发现,自然环境、市场环境、政策环境、产业链延伸、价值链增值、协作动力、订单制度安排、绿色生产、绩效增加和农户增收10个主范畴是影响新型农业经营主体发展水稻订单模式的重要因素。继而,以订单模式为中心范畴,构建起“环境—价值(产业)链—协作动力—制度安排—共生共赢”的新型运作机制。最后,立足水稻订单模式发展共生共赢的根本目标,剖析企业绩效增加和农业绿色生产赋能粮农增收的具体路径。 展开更多
关键词 水稻订单模式 粮农增收 运作机制 优化路径 扎根理论
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基于契约合作视域下农牧电商产业学院产教融合运行机制建构研究
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作者 陈杰 《现代农业研究》 2024年第11期112-115,共4页
在数字经济飞速发展的背景下,农牧电商产业正逐渐成为推动农牧业现代化和乡村振兴的重要力量。农牧电商产业不仅为农牧产品的流通和销售提供了全新的渠道,同时也对传统的农牧业经营模式和管理方式提出了挑战。农牧电商产业的健康发展,... 在数字经济飞速发展的背景下,农牧电商产业正逐渐成为推动农牧业现代化和乡村振兴的重要力量。农牧电商产业不仅为农牧产品的流通和销售提供了全新的渠道,同时也对传统的农牧业经营模式和管理方式提出了挑战。农牧电商产业的健康发展,需要农牧电商产业学院与相关企业深度合作,共同推动人才培养、技术创新和产业升级。本文以农牧电商产业学院产教融合实践为例,深入探究产教融合实践逻辑及运行机制,以期突破以往多数产教融合关系不可持续的难题,并尝试从关系契约视角提出农牧电商产业学院产教融合优化的建议。 展开更多
关键词 契约合作 产业学院 运行机制 建构研究
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既有建筑绿色改造项目ESCO风险预警机制研究架构
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作者 郭汉丁 王明宇 张印贤 《科技和产业》 2024年第21期225-231,共7页
既有建筑绿色改造是践行节能减排和“双碳”目标的建筑实践,是城市更新背景下建筑业高质量可持续发展的内在要求,是建筑业新建改建并举业态转型的实际行动。EPC(合同能源管理)模式下既有建筑绿色改造有序实施关键在于ESCO(节能服务企业... 既有建筑绿色改造是践行节能减排和“双碳”目标的建筑实践,是城市更新背景下建筑业高质量可持续发展的内在要求,是建筑业新建改建并举业态转型的实际行动。EPC(合同能源管理)模式下既有建筑绿色改造有序实施关键在于ESCO(节能服务企业)风险治理。基于项目治理视角,从国内外工程项目风险预警研究概述入手,解析ESCO风险治理的特殊复杂性,论证ESCO既有建筑绿色改造项目风险预警机制研究价值,设计ESCO风险预警机制研究目标,规划既有建筑绿色改造项目ESCO风险预警机制的内容,阐释ESCO风险预警机制研究思路、创新之处和体系构架的实施方案及其可行性,初步形成基于项目治理视角的ESCO既有建筑绿色改造项目风险预警理论体系。丰富与完善风险治理理论,以治理有效驱动绿色改造高质量发展。 展开更多
关键词 既有建筑绿色改造 EPC(合同能源管理)模式 ESCO(节能服务企业) 风险预警 运行机制 体系架构
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