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形象二元结构与价值单维选择——黄瑞云寓言研究之一 被引量:2
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作者 张开焱 《湖北师范学院学报(哲学社会科学版)》 1997年第1期45-51,共7页
在语言艺术诸种类中,寓言因其类型性、哲理性、象征性等固有特征和规范的限制,大约是最不适宜于直接而鲜明地体现创作主体个性特征的一种.但黄瑞云先生的寓言却提供了这样一个范例:在一个有着独特的心理构成、强大的人格力量和极大艺术... 在语言艺术诸种类中,寓言因其类型性、哲理性、象征性等固有特征和规范的限制,大约是最不适宜于直接而鲜明地体现创作主体个性特征的一种.但黄瑞云先生的寓言却提供了这样一个范例:在一个有着独特的心理构成、强大的人格力量和极大艺术创造力的作家笔下,寓言显现主体个性的限制和困难会在多大程度上被突破克服.读他的寓言,你不可能不有这样强烈的感觉,这些寓言只是他的,他把自己独特的心理图式和人格形象深深地镌刻进了他寓言的象征世界. 展开更多
关键词 黄瑞云寓言 二元对立结构 象征世界 二元结构 寓言形象 价值单 心理图式 价值判断 认知图式 语言艺术
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桉树无性系的单板出材率与价值研究 被引量:14
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作者 任世奇 罗建中 +4 位作者 彭彦 谢耀坚 卢万鸿 曹加光 姜英 《草业学报》 CSCD 北大核心 2010年第6期46-54,共9页
为了系统深入地对单板出材率和价值的影响因素进行研究,以11个6年生桉树无性系为材料,使用无损检测仪器Pilodyn和Fakopp测定立木的外部密度和应力波传输速度,用轴向生长应变仪器CIRAD-Forest Method测定立木生长应力,结合对原木外观形... 为了系统深入地对单板出材率和价值的影响因素进行研究,以11个6年生桉树无性系为材料,使用无损检测仪器Pilodyn和Fakopp测定立木的外部密度和应力波传输速度,用轴向生长应变仪器CIRAD-Forest Method测定立木生长应力,结合对原木外观形质的检测和单板质量等级的划分,运用差异性分析、相关分析及多元逐步回归分析。结果表明,无性系间立木的材性性状,原木形质中的小头最小直径、弯曲度和端裂指数存在显著差异。节疤,尤其死节(孔洞)、裂缝是降低单板等级的主要因素。无性系间单板出材率和价值存在显著差异,其中出材率(%)从大到小排序为:GL9(48.27),EC34(47.17),LH1(44.00),DH32-22(42.00),GL4(37.56),SH7(34.88),UC184-1(34.38),LH5(31.06),M1(29.74),DH201-2(25.41),SG1(16.28),最大是最小的2.97倍;单段原木价值(RMB/log)从高到低排序为:EC34(13.37),GL9(13.12),GL4(12.36),LH1(12.02),DH32-22(11.55),LH5(10.72),SH7(9.22),UC184-1(7.95),M1(7.55),DH201-2(5.97),SG1(4.88),最高是最低的2.74倍;单位材积价值(RMB/m3)从高到低排序为:EC34(856.49),LH1(794.55),GL9(788.68),DH32-22(763.02),GL4(681.44),SH7(629.35),UC184-1(597.66),LH5(559.08),M1(538.39),DH201-2(450.49),SG1(294.53),最高是最低的2.91倍。5个品种的无性系作为胶合板用材,尾巨桉无性系价值最高。原木弯曲度是影响单板出材率和价值的主要因素,木材密度、小头直径、应力波传输速度及端裂指数等对其也有显著影响。无损检测仪器Pilodyn和Fakopp可对单板出材率和单位材积价值进行粗略预测。 展开更多
关键词 桉树无性系 材性性状 原木外观形质 板出材率与价值
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桉木单板出材率与价值影响因子研究 被引量:5
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作者 任世奇 罗建中 +4 位作者 谢耀坚 彭彦 陈健波 卢万鸿 姜英 《桉树科技》 2010年第2期1-7,共7页
以4个品种的10个6年生桉树无性系为材料,进行立木生长性状调查、原木外观形质检测和单板质量等级划分,运用方差分析、相关分析及多元回归分析,系统地对单板出材率与价值影响因子进行研究。结果表明:4个品种的无性系单板材以尾巨桉无性... 以4个品种的10个6年生桉树无性系为材料,进行立木生长性状调查、原木外观形质检测和单板质量等级划分,运用方差分析、相关分析及多元回归分析,系统地对单板出材率与价值影响因子进行研究。结果表明:4个品种的无性系单板材以尾巨桉无性系价值最高。无性系间立木生长性状存在极显著差异,其中树皮厚度差异最大。单板外观缺陷中的节子,尤其死节(孔洞)、裂缝是降低单板质量等级的主要因子。材积、弯曲度和尖削度是影响单板出材率与价值的主要因子。建立的单板出材率、单段原木价值和单位材积价值预测模型,对指导生产经营具有一定的意义。 展开更多
关键词 桉树无性系 生长性状 原木外观形质 板出材率与价值
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基于单边界二分式条件价值法的洞穴旅游资源非使用价值评估——以重庆芙蓉洞为例 被引量:5
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作者 张枫怡 杨晓霞 +1 位作者 向旭 杨逸枫 《中国岩溶》 CAS CSCD 北大核心 2019年第1期130-138,共9页
为提高公众对洞穴旅游资源非使用价值的重视程度,以世界自然遗产地芙蓉洞为研究对象,采用单边界二分式条件价值法,以到芙蓉洞景区旅游的游客、重庆市民为调查对象,对芙蓉洞洞穴旅游资源的非使用价值进行评估。其结果表明:芙蓉洞洞穴旅... 为提高公众对洞穴旅游资源非使用价值的重视程度,以世界自然遗产地芙蓉洞为研究对象,采用单边界二分式条件价值法,以到芙蓉洞景区旅游的游客、重庆市民为调查对象,对芙蓉洞洞穴旅游资源的非使用价值进行评估。其结果表明:芙蓉洞洞穴旅游资源非使用价值的平均支付意愿为330.49元,非使用价值总额为229.82亿元,远大于其门票收入;芙蓉洞洞穴旅游资源非使用价值的平均支付意愿大小与被调查者对芙蓉洞非使用价值的了解程度、婚姻状况、年龄、职业、年收入、文化程度、人均出游花销显著相关。今后应加强对芙蓉洞非使用价值的认知,通过多种渠道宣传芙蓉洞的非使用价值,多方合力,共同保护芙蓉洞洞穴旅游资源。 展开更多
关键词 洞穴旅游资源 非使用价值 边界二分式条件价值 芙蓉洞
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基于询单价值和交期的预排产技术在线缆制造业应用研究 被引量:1
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作者 王正成 《制造业自动化》 CSCD 北大核心 2021年第10期153-156,共4页
为提高线缆制造业生产排产的科学性及增强其客户满意度水平,系统提出线缆制造业基于询单价值的交期预排产方法及实现技术。论文首先提出了基于询单价值的预排产过程模型,确立了论文总体研究思路;其次建立了线缆制造业客户询单价值的计... 为提高线缆制造业生产排产的科学性及增强其客户满意度水平,系统提出线缆制造业基于询单价值的交期预排产方法及实现技术。论文首先提出了基于询单价值的预排产过程模型,确立了论文总体研究思路;其次建立了线缆制造业客户询单价值的计算模型与方法,并给出了基于询单价值的选择决策矩阵;在此基础上提出基于询单价值结合可用物料与产能的预排产模型与实现方法,最后通过一仿真算例验证了本文所提模型与方法的有效性。 展开更多
关键词 价值 预排产 线缆制造业 决策矩阵
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基于原木法估算立木收益价值的实证研究 被引量:1
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作者 张莉莉 《林业经济问题》 北大核心 2010年第4期283-287,334,共6页
以林木市场价格为基础,采用原木法对杉木人工林的经济收益价值的估算进行实证分析,并对其应用范围和应用价值进行了研究,为林木经营者提供了做出最佳林木产出决策的思路和建议。
关键词 林木资源 原木价值 立木收益估算
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刷单行为的类型、成因及其规制 被引量:1
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作者 王超 《福建警察学院学报》 2020年第1期95-100,共6页
刷单行为包括虚增价值型刷单、贬低价值型刷单、欺骗平台型刷单和误导平台型刷单四种类型,其中虚增价值型刷单是其最主要形式。刷单行为产生的根本原因是在电子商务环境中经营者与消费者、平台维护者、监管者之间的信息不对称。基于此,... 刷单行为包括虚增价值型刷单、贬低价值型刷单、欺骗平台型刷单和误导平台型刷单四种类型,其中虚增价值型刷单是其最主要形式。刷单行为产生的根本原因是在电子商务环境中经营者与消费者、平台维护者、监管者之间的信息不对称。基于此,应通过丰富刷单行为的信息采集渠道,采取平台监管优先于行政监管的监管方式,构建起行政责任、民事责任和刑事责任并举的责任体系,以规制刷单行为。 展开更多
关键词 行为 虚增价值型刷 信息不对称 平台监管
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集中监控下的工单派发研究
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作者 曾俊 《信息通信》 2017年第10期262-263,共2页
告警快速发现与及时处理,对企业的业务推广、市场规模扩大、客户感知改善、企业形象提升具有重要影响。早期的2/3G网络中,告警发现与派单模式,基本上采用"告警全面工单化"的模式。进入4G时代,业务种类井喷,网元类型和数量暴增... 告警快速发现与及时处理,对企业的业务推广、市场规模扩大、客户感知改善、企业形象提升具有重要影响。早期的2/3G网络中,告警发现与派单模式,基本上采用"告警全面工单化"的模式。进入4G时代,业务种类井喷,网元类型和数量暴增,传统的告警管理模式呈现出工单价值低、故障调度滞后、客户感知下滑等现象。针对这些不足,特开展集中监控模式下的工单派发机制研究,在提升工单派发准确率的同时,全面为维护人员减负。 展开更多
关键词 告警 集中监控 EOMS 派发 价值
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Dynamic optimization of cutoff grade in underground metal mining 被引量:3
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作者 顾晓薇 王青 +1 位作者 初道忠 张斌 《Journal of Central South University》 SCIE EI CAS 2010年第3期492-497,共6页
In order to maximize the overall economic gain from a metal mine operation, selection of cutoff grades must consider two important aspects: the time value of money and the spatial variation of the grade distribution i... In order to maximize the overall economic gain from a metal mine operation, selection of cutoff grades must consider two important aspects: the time value of money and the spatial variation of the grade distribution in the deposit. That is, cutoff grade selection must be dynamic with respect to both time and space. A newly developed method that fulfills these requirements is presented. In this method, the deposit or a portion of it under study is divided into "decision units" based on the mining method and sample data. The statistical grade distribution and the grade-tonnage relationship of each decision unit are then computed based on the samples falling in the unit. Each decision unit with its grade-tonnage relationship is considered as a stage in a dynamic programming scheme and the problem is solved by applying a forward dynamic programming based algorithm with an objective function of maximizing the overall net present value (NPV). A software package is developed for the method and applied to an underground copper mine in Africa. 展开更多
关键词 cutoff grade OPTIMIZATION dynamic programnaing underground metal mining
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Fodder Value of Populus euramericana Green Biomass 被引量:1
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《Journal of Agricultural Science and Technology(B)》 2012年第5期498-509,共12页
The study of green mass nutritional value of the black poplars euramerican hybrids--Populus euramericana (Dode) Guinier was conducted. The content of fodder units, digestible and crude protein, crude fat, fiber, ash... The study of green mass nutritional value of the black poplars euramerican hybrids--Populus euramericana (Dode) Guinier was conducted. The content of fodder units, digestible and crude protein, crude fat, fiber, ash, nitrogen, calcium, phosphorus, carotene and others was studied. The study showed that the leaves had greater nutritional value than stems and branches. The fresh leaves collected from the annual shoots of trees were more nutritious than annual coppice shoots of reproductive plantations but after drying the nutritional value of the materials became similar. Indicators of stems nutritional value were similar to those of wheat straw and those of leaves that were close to the nutritional value of alfalfa. Nutritional value of leafy shoots was intermediate between that of stems and leaves. Young coppice plant material is much easier to harvest than that of mature trees. Minirotation cultivation of poplars allows obtaining significant reserves of both wood and leafing biomass in a short period of time per unit area. The "old clones" of euramerican hybrids of black poplars are more winter resistant than some southern poplars of Italian breeding. This allows cultivating them not only in places of habitual areas of poplars, but also in more Northern regions. 展开更多
关键词 Euramerican poplars fodder value green biomass of trees chemical composition of fodder.
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Existence of Positive Solution for Superlinear Semipositone Singular Second-order m-point Boundary Value Problem 被引量:4
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作者 ZHANG Xing-qiu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期151-158,共8页
By applying fixed point theorem, the existence of positive solution is considered for superlinear semipositone singular m-point boundary value problem -(Lφ)(x)=(p(x)φ′(x))′+q(x)φ(x) and ξi ∈ (0,... By applying fixed point theorem, the existence of positive solution is considered for superlinear semipositone singular m-point boundary value problem -(Lφ)(x)=(p(x)φ′(x))′+q(x)φ(x) and ξi ∈ (0,1)with 0〈ξ1〈ξ2……〈ξm-2〈1,αi ∈ R^+,f ∈C[(0,1)×R^+,R^+],f(x,φ) may be singular at x=0 and x=1,g(x):(0,1)→R is Lebesgue measurable, g may tend to negative infinity and have finitely many singularities. 展开更多
关键词 SEMIPOSITONE SUPERLINEAR singular m-point boundary value fixed point theo-rem positive solution
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Refurbishing Faestningens Materialgard: A Heritage Complex
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作者 Torben Valdbjom Rasmussen 《Journal of Civil Engineering and Architecture》 2014年第7期888-897,共10页
F estningens Materialgard is a listed complex located in downtown Copenhagen. The refurbishment of the listed complex was studied to provide knowledge on how a process for refurbishing heritage buildings can be carri... F estningens Materialgard is a listed complex located in downtown Copenhagen. The refurbishment of the listed complex was studied to provide knowledge on how a process for refurbishing heritage buildings can be carried out successfully, as refurbishment of heritage buildings is often a complicated process. The process shows how to choose, evaluate and implement measures creating synergy between the interests of preserving heritage values and to develop affordable refurbishment that meets the requirements for the future use of the building. The refurbishment followed included restoration, energy upgrading and refurbishment of the individual buildings that make up the listed complex. The process focuses on the cooperation and dialogue between the parties involved. F estningens Materialgard is a case study where the Heritage Agency, the Danish Working Environment Authority and the owner as a team cooperated in identifying feasible refurbishment measures. Through the process the owner was supported by architects and engineers. Focus is put on how, to identify potential energy savings and, to decide on energy upgrading measures when refurbishing and restoring listed buildings. The refurbished Faestningens Materialgard is visualized in photos. 展开更多
关键词 BUILDING HERITAGE refurbishment.
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Invariants for a Class of Nongeneric Three-Qubit States
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作者 SUN Bao-Zhi FEI Shao-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1007-1010,共4页
We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations are presented for a class of non-generic three-qubit mixed states.... We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations are presented for a class of non-generic three-qubit mixed states. It is shown that two such states in this class are locally equivalent if and only if all these invariants have equal values for them. 展开更多
关键词 INVARIANT quantum state local unitary transformation
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Clinical Value of Dual-energy CT in Detection of Pancreatic Adenocarcinoma: Investigation of the Best Pancreatic Tumor Contrast to Noise Ratio 被引量:2
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作者 Yong-lan He Da-ming Zhang +1 位作者 Hua-dan Xue Zheng-yu Jin 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第4期207-212,共6页
Objective To quantitatively compare and determine the best pancreatic tumor contrast to noise ratio (CNR) in different dual-energy derived datasets. Methods In this retrospective, single center study, 16 patients (9 m... Objective To quantitatively compare and determine the best pancreatic tumor contrast to noise ratio (CNR) in different dual-energy derived datasets. Methods In this retrospective, single center study, 16 patients (9 male, 7 female, average age 59.4±13.2 years) with pathologically diagnosed pancreatic cancer were enrolled. All patients received an abdominal scan using a dual source CT scanner 7 to 31 days before biopsy or surgery. After injection of iodine contrast agent, arterial and pancreatic parenchyma phase were scanned consequently, using a dual-energy scan mode (100 kVp/230 mAs and Sn 140 kVp/178 mAs) in the pancreatic parenchyma phase. A series of derived dual-energy datasets were evaluated including non-liner blending (non-linear blending width 0-500 HU; blending center -500 to 500 HU), mono-energetic (40-190 keV), 100 kVp and 140 kVp. On each datasets, mean CT values of the pancreatic parenchyma and tumor, as well as standard deviation CT values of subcutaneous fat and psoas muscle were measured. Regions of interest of cutaneous fat and major psoas muscle of 100 kVp and 140 kVp images were calculated. Best CNR of subcutaneous fat (CNR F ) and CNR of the major psoas muscle (CNR M ) of non-liner blending and mono-energetic datasets were calculated with the optimal mono-energetic keV setting and the optimal blending center/width setting for the best CNR. One Way ANOVA test was used for comparison of best CNR between different dual-energy derived datasets. Results The best CNR F (4.48±1.29) was obtained from the non-liner blending datasets at blending center -16.6±103.9 HU and blending width 12.3±10.6 HU. The best CNR F (3.28±0.97) was obtained from the mono-energetic datasets at 73.3±4.3 keV. CNR F in the 100 kVp and 140 kVp were 3.02±0.91 and 1.56±0.56 respectively. Using fat as the noise background, all of these images series showed significant differences (P<0.01) except best CNR F of mono-energetic image sets vs. CNR F of 100 kVp image (P=0.460). Similar results were found using muscle as the noise background (mono-energetic image vs. 100 kVp image: P=0.246; mono-energetic image vs. non-liner blending image: P=0.044; others: P<0.01). Conclusion Compared with mono-energetic datasets and low kVp datasets, non-linear blending image at automatically chosen blending width/window provides better tumor to the pancreas CNR, which might be beneficial for better detection of pancreatic tumors. 展开更多
关键词 pancreatic adenocarcinoma DUAL-ENERGY contrast to noise ratio non-linear blending
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Diagnostic and monitoring values of circulating AFPmRNA and HS-GGT for hepatocellular carcinoma
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作者 Li Wang Min Yao +3 位作者 Yao Yao Liuhong Pan Shaolin Lu Dengfu Yao 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第10期457-463,共7页
Objective: Early finding of hepatocellular carcinoma(HCC) and monitoring of its metastasis are of the utmost importance. The objectives of this study were to investigate the values of circulating hepatoma-specific gam... Objective: Early finding of hepatocellular carcinoma(HCC) and monitoring of its metastasis are of the utmost importance. The objectives of this study were to investigate the values of circulating hepatoma-specific gamma-glutamyl transferase(HS-GGT) fraction and α-fetoprotein mRNA(AFP-mRNA) from peripheral blood mononuclear cells(PBMCs) in diagnosis or monitoring metastasis of HCC. Methods: Total RNA was extracted from hepatomas or PBMCs of patients, synthesized to AFP-cDNA through random primers and reverse transcriptase, amplified by using a nested PCR assay, and confirmed by sequencing. Simultaneity, the HS-GGT activities were quantitatively determined in sera of patients. The comprehensive assessments of two markers were investigated in HCC patients. Results: The amplified fragments of AFP-mRNA were identical to original designed ones(159 bp) and confirmed by sequencing. The lowest sensitivity was 2 ng/L of total RNA. The incidences of AFP-mRNA and HS-GGT were 60.4%(113 of 187) and 84.5%(158 of 187) in the HCC group, and their significantly higher(P < 0.01) than that in any of other groups. The high frequencies of HS-GGT and AFP-mRNA were 78.2% and 56.4% in the HCC patients with AFP < 50 ng/mL. All positive of AFP-mRNA was found in HCC patients with extrahepatic metastasis. No significant correlation was found between tumor size and AFP-mRNA or HS-GGT. The total incidence of combined AFP-mRNA and HS-GGT detection was 93.6 % for HCC diagnosis. Conclusion: HS-GGT and AFP-mRNA are specific markers for HCC diagnosis or differentiation, especially the former for early finding and the later for monitoring metastasis of HCC. 展开更多
关键词 hepatocellular carcinoma(HCC) AFP-MRNA hepatoma-specific gamma-glutamyl transferase diagnosis metastasis
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Study on engineering audit based on Valuation
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作者 Wei Zuo Xiaoli Hu Lili Dou 《International English Education Research》 2015年第3期38-39,共2页
in the bill of quantities mode, audit department how to perform the function of supervision, control the cost of the project, to improve the infrastructure investment efficiency to have the important meaning. This art... in the bill of quantities mode, audit department how to perform the function of supervision, control the cost of the project, to improve the infrastructure investment efficiency to have the important meaning. This article from the valuation list elements of engineering audit mode based solutions, engineering audit under BOQ valuation mode is put forward from the audit information management, engineering contract claim, audit personnel quality etc.. 展开更多
关键词 list valuation project audit BIDDING
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增额终身寿险内嵌退保期权风险研究
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作者 周书正 刘迪 《保险研究》 CSSCI 北大核心 2024年第10期44-58,共15页
市场利率持续下行,后疫情时代居民预防性储蓄意愿变强,增额终身寿险因其长期保证收益、灵活领取等特征,迅速成为市场追捧对象。另一方面,保险公司近年来在业绩增长和销售队伍维持方面承受一定压力,增额终身寿险易于销售,且在当前价值评... 市场利率持续下行,后疫情时代居民预防性储蓄意愿变强,增额终身寿险因其长期保证收益、灵活领取等特征,迅速成为市场追捧对象。另一方面,保险公司近年来在业绩增长和销售队伍维持方面承受一定压力,增额终身寿险易于销售,且在当前价值评估体系下有着较高的新单价值,所以从供给角度保险公司也更倾向推动该产品销售。然而,增额终身寿险有两大风险,一是利率下行导致的利差损风险,二是市场利率波动引发的退保风险。本文聚焦增额终身寿险内嵌退保期权特征,将市场利率上行引发的退保类比为美式看跌期权的行权行为,通过美式期权定价方法,量化增额终身寿险内嵌退保期权成本,并讨论如何在产品新单价值中反映其风险。研究发现,内嵌退保期权对典型增额终身寿险产品的新单价值影响显著。本文建议:险企在制定产品策略时应充分考虑内嵌期权的风险特征,在新产品开发时,可考虑增加退保现金价值的市值调整权,降低面临的不可控风险;对于已经销售大量增额终身寿险保单且财务状况或偿付能力严重恶化的险企,监管也可考虑研究制定对存量保单退保现金价值进行市值调整的管理制度。 展开更多
关键词 增额终身寿 退保期权 风险管理 价值
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Nonlinear fastest growing perturbation and the first kind of predictability 被引量:28
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作者 穆穆 王家城 《Science China Earth Sciences》 SCIE EI CAS 2001年第12期1128-1139,共12页
Nonlinear fastest growing perturbation, which is related to the nonlinear singular vector and nonlinear singular value proposed by the first author recently, is obtained by numerical approach for the two-dimensional q... Nonlinear fastest growing perturbation, which is related to the nonlinear singular vector and nonlinear singular value proposed by the first author recently, is obtained by numerical approach for the two-dimensional quasigeostrophic model in this paper. The difference between the linear and nonlinear fastest growing perturbations is demonstrated. Moreover, local nonlinear fastest growing perturbations are also found numerically. This is one of the essential differences between linear and nonlinear theories, since in former case there is no local fastest growing perturbation. The results show that the nonlinear local fastest growing perturbations play a more important role in the study of the first kind of predictability than the nonlinear global fastest growing perturbation. 展开更多
关键词 singular vector singular value NONLINEAR PREDICTABILITY
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Design and evaluation of control systems for a real canal 被引量:6
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作者 SHANG YiZi ROGERS Peter WANG GuangQian 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第1期142-154,共13页
The distant downstream proportional integral(PI) feedback control was applied to the W-M lateral canal of the Maricopa Stanfield Irrigation and Drainage District located in central Arizona,U.S.A.Proper configuration o... The distant downstream proportional integral(PI) feedback control was applied to the W-M lateral canal of the Maricopa Stanfield Irrigation and Drainage District located in central Arizona,U.S.A.Proper configuration of those controls for the ca-nal can be challenging.Towards this end,an integrated approach to the design of an automatic control system for the canal was proposed.This approach presented herein is not only a systematical review of previous work,but also represents a further ad-vance of the previous simulation study by Tsinghua University(Shang et al,2011) on relating the canal control algorithm to local PI controls for the real canal.To evaluate the control system potential,performance of the control algorithm that was ob-tained through implanting predicative module into linear quadratic regulator(LQR) was analyzed with singular value bode.Additional "manufactured" tests were conducted to compare with the control system that is currently in use.The results indi-cated that the developed control system rather than the system in current use had considerable potential to closely match dis-charge at the downstream check structures with those ordered by water users while maintaining the water level throughout the length of the canal. 展开更多
关键词 canal control system singular value bode proportional integral (PI) control linear quadratic regulator (LQR)
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Linear low-rank approximation and nonlinear dimensionality reduction 被引量:2
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作者 ZHANG Zhenyue & ZHA Hongyuan Department of Mathematics, Zhejiang University, Yuquan Campus, Hangzhou 310027, China Department of Computer Science and Engineering, The Pennsylvania State University, University Park, PA 16802, U.S.A. 《Science China Mathematics》 SCIE 2004年第6期908-920,共13页
We present our recent work on both linear and nonlinear data reduction methods and algorithms: for the linear case we discuss results on structure analysis of SVD of columnpartitioned matrices and sparse low-rank appr... We present our recent work on both linear and nonlinear data reduction methods and algorithms: for the linear case we discuss results on structure analysis of SVD of columnpartitioned matrices and sparse low-rank approximation; for the nonlinear case we investigate methods for nonlinear dimensionality reduction and manifold learning. The problems we address have attracted great deal of interest in data mining and machine learning. 展开更多
关键词 singular value decomposition low-rank approximation sparse matrix nonlinear dimensionality reduction principal manifold subspace alignment data mining
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