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IT广告的信息直接表现、理性比较和证言表现策略
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作者 陈冠 李涛 +1 位作者 覃明 袁希 《电子出版》 2004年第8期3-4,共2页
广告讯息策略的表现水平高低直接影响广告的最终效传播果,出色的广告表现策略可以使正确的讯息策略产生极其强烈的反应市场,广告表现不力则会使正确的广告讯息策略毫无效果。
关键词 IT广告 营销策略 理性比较 证言表现策略 信息直接表现
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Soil Physical and Chemical Properties of Five Subtropical Forests in Lingao of Hainan
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作者 薛杨 宿少锋 +1 位作者 王小燕 林之盼 《Agricultural Science & Technology》 CAS 2017年第8期1459-1464,共6页
With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosi... With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosity was the highest in the Casuarina equisetifolia forest (46.168%), but the lowest in the Encalyptus robusta forest (39.46%). The soil capillary porosity was the highest in the Acacia mangium forest (22.57%), but the lowest in the secondary forest (18.95%). The soil water content was the highest in the C. equisetifolia forest, with a mean value of 27.85%, but the lowest in the secondary forest, with a mean value of 4.34%. The soil pH values were in the range of 4.81-6.59, the soils in the A. mangium forest, C. equisetifolia forest and E. robusta forest were strongly acidic (pH 4.5-5.5), and the soils in the secondary forest and C. nucifera forest were weakly acidic. The soils had organic matter contents in the range of 0.34-28.68 g/kg, and showed an order of A. mangium forest〉C. equisetifolia forest〉E. robusta forest〉secondary forest〉C. nucifera forest, with a decreasing trend with the soil depth increasing. The soil total N contents were in the range of 0.10-1.63 g/kg, the A. mangium forest showed the highest soil total N contents, while the C. nucifera forest exhibited the lowest soil total N contents; the soil total P contents were in the range of 0.21-1.74 g/kg, and the E. robusta forest had the highest soil total P contents; and the soil total K contents were in the range of 0.16-2.15 g/kg, and the A. mangium forest exhibited the highest soil total K contents. The soil available P contents were in the range of 0.98-132.46 mg/kg; and the secondary forests had the highest soil available P contents; and the soil rapidly available K contents were in the range of 3.03-27.35 mg/kg, and the C. nucifera forest exhibited the highest soil rapidly available K contents. The soil ammonium N contents were in the range of 1.38-5.15 mg/kg, and the nitrate N contents were in the range were in the range of 0.56 -3.51 mg/kg. The A. mangium forest showed the highest soil nitrate N contents (with a mean value of 2.29 mg/kg) and ammonium N contents (with a mean value of 3.93 mg/kg). For the same forest type, with the increase of soil depth, the nitrate nitrogen and ammonium nitrogen content also showed a decreasing trend. 展开更多
关键词 Lingao County Coastal platform Different forest types Soil physical and chemical properties COMPARISON
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我国融资体系困境之对策探析
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作者 敖淑青 《广播电视大学学报(哲学社会科学版)》 1999年第1期13-16,共4页
作为金融体系的核心部分,融资活动也同样是一个系统和综合体。目前,我国融资体系处于困境,这一困境是指其运行的不良状态或非正常运行。针对我国融资体系困境的状况和性质,结合国情,应采取三个策略:一是建立有效的储蓄向投资转化... 作为金融体系的核心部分,融资活动也同样是一个系统和综合体。目前,我国融资体系处于困境,这一困境是指其运行的不良状态或非正常运行。针对我国融资体系困境的状况和性质,结合国情,应采取三个策略:一是建立有效的储蓄向投资转化的融资机制;二是理性比较分析直接融资和间接融资两种融资方式的效率;三是建立投资银行实现资本重组等对策,以选择恰当的战略模式,建立完善的融资体系。 展开更多
关键词 破立结合 系统综合 融资机制 理性比较 资本重组
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A Class of Nonlocal Boundary Value Problems for Elliptic Systems in Unbounded Domains
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作者 莫嘉琪 张汉林 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期29-33,共5页
A class of nonlocal boundary value probl em s for elliptic systems in the unbounded domains are considered. Under suitable c onditions, the existence of solution and the comparison theorem for the boundary value prob... A class of nonlocal boundary value probl em s for elliptic systems in the unbounded domains are considered. Under suitable c onditions, the existence of solution and the comparison theorem for the boundary value problems are studied. 展开更多
关键词 elliptic system boundary value problem c omparison theorem
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对众数公式的改进
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作者 蔡建强 《平顶山学院学报》 1998年第2期20-21,27,共3页
关键词 众数组 表达式 比例推算法 近似计算公式 同向变化 反向变化 等距数列 定性分析 理性比较 变量数列
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Analysis of Irrigation Systems Employing Comparative Performance Indicators: A Benchmark Study for National Irrigation and Communal Irrigation Systems in Cagayan River Basin
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作者 Jeoffrey Lloyd Reyes Bareng Orlando Florendo Balderama Lanie Alejandro Alejo 《Journal of Agricultural Science and Technology(A)》 2015年第5期325-335,共11页
Comparative performance analysis of four irrigation schemes within Cagayan River Basin was assessed using comparative performance indicators between the years 2008 and 2012. The objectives were to establish benchmarks... Comparative performance analysis of four irrigation schemes within Cagayan River Basin was assessed using comparative performance indicators between the years 2008 and 2012. The objectives were to establish benchmarks for both productivity and performance of irrigation schemes along the valley and to inquire whether small schemes function better than large schemes. The performance evaluation study of the systems composed of three general performance indicators, based on three domains-(1) system operation performance; (2) agricultural productivity and economics; (3) financial performance. Each indicator was assessed based on the prescribed descriptors used by the International Water Management Institute (IWMI) and Food and Agriculture Organization (FAO). Analysis showed an overall system performance efficiency of 59%, 55%, 47% and 36% for Magat River Integrated Irrigation System (MARI1S), Lucban, Garab and Divisoria Communal Irrigation Systems (CIS), respectively. In terms of annual productivity performance, Lucban CIS dominates the three other systems with 0.35 kg/m3, which was classified as moderately performing system, while the rest were classified with low productivity index. Financial sustainability of the systems were extremely poor with cost recovery ratio of 0, 0.33, 0.41 and 0.49 for Divisoria, Garab, Lucban and MARIIS, respectively, which were exceptionally below the standard value of at least one. Also, analysis of the indicators revealed that on average, large schemes performed similarly to small-scale schemes, but small schemes were more variable, particularly in input-use efficiency. The benchmarking study will provide strategic information to policy makers of agricultural and irrigation agencies on the existing weaknesses of irrigation systems in the country and determine in a more quantifiable terms levels of potential improvement and intervention targets. 展开更多
关键词 Communal and national irrigation systems performance benchmarking small and large reservoir schemes.
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Hydraulic Characteristics of Low Crested Structures under Wave Attack
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作者 I.G.B. Siladharma D.M. Sulaiman 《Journal of Shipping and Ocean Engineering》 2011年第3期141-149,共9页
Two-dimensional physical models of low crested breakwaters were tested to establish the effect of water depth, crest width, slope, stone size, core permeability and incident wave characteristics on the wave transforma... Two-dimensional physical models of low crested breakwaters were tested to establish the effect of water depth, crest width, slope, stone size, core permeability and incident wave characteristics on the wave transformation processes. The structure of the breakwaters can be used as coastal protection system by reducing the amount of incoming wave energy. Effect of slope, core permeability, water depth and incident wave characteristics on the stability was also studied. The breakwater model consisted of a core and two armour layers attacked by irregular waves. This paper discusses and compares the test results with the existing design equations. In general, the existing design equations do not seem to predict the wave transmission and reflection accurately for the range of test data. In the range of variable tested, it was observed that the water depth, crest width and wave period have a significant influence on wave transmission process. Further, results show strong influence of the water depth and wave period on the wave reflection process. The structural stability of low crested breakwaters is very much affected by the water depth and wave period. 展开更多
关键词 Low crested structures wave transmission and reflection hydraulic characteristics structure stability.
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国际融资租赁——我国水电行业利用外资的新思考
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作者 程鹏 《水利水电工程造价》 1996年第3期38-40,共3页
我国水能资源量居世界之首,但开发程度不高,资金不足是制约水电发展的主要因素。为加快我国水电发展速度,除国内积极筹资,利用国际金融组织(含政府)贷款和出口信贷外,国际融资租赁也是一种可供选择的途径。融资租赁是出租人将实质属于... 我国水能资源量居世界之首,但开发程度不高,资金不足是制约水电发展的主要因素。为加快我国水电发展速度,除国内积极筹资,利用国际金融组织(含政府)贷款和出口信贷外,国际融资租赁也是一种可供选择的途径。融资租赁是出租人将实质属于资产所有权人的一切风险和报酬,转移给承担人的一种租赁。出口信贷往往条件苛刻,加重进口国债务负担。而国际融资租赁进口国可以享受较多的税收优惠;且手续简单,租金较低,时间较长,还可节省自有资金。然而,融资租赁的典型特征是出租人是设备的所有者,承租人是设备的使用者,且承租人风险较大。 展开更多
关键词 国际融资租赁 利用外资 理性比较
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Phase group synchronization between any signals and its physical characteristics 被引量:2
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作者 DU BaoQiang SHI LinLin +4 位作者 CHEN YaoMing DONG ShaoFeng YANG ZhiGang CAO LingZhi GUO ShuTing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第4期674-679,共6页
The phase group synchronization between any signals is further revealed,which is based on proposing the new concepts of the greatest common factor frequency,the least common multiple period,quantized phase shift resol... The phase group synchronization between any signals is further revealed,which is based on proposing the new concepts of the greatest common factor frequency,the least common multiple period,quantized phase shift resolution,equivalent phase comparison frequency and so on.Then the problem of phase comparison and processing between different frequency signals is solved and shown in detail.Using the basic principle and the variation law of group phase difference,the frequency stability better than 10-14/s can be easily obtained in the time&frequency measurement and control domain,and experimental results also show the phase relations between atomic energy level transition signal and the locked crystal oscillator signal in an active hydrogen atomic clock are strict phase group synchronization,and locked precision with 10-13/s can be reached based on phase group synchronization.The phase group synchronization can provide technical support to frequency linking among radio frequency,microwave and light frequency. 展开更多
关键词 equivalent phase comparison frequency least common multiple period group phase difference group period phase processing phase group synchronization
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Variational formula for the stability of regime-switching diffusion processes 被引量:1
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作者 Jinghai Shao Lingdi Wang 《Science China Mathematics》 SCIE CSCD 2018年第4期659-676,共18页
The asymptotical stability in probability is studied for diffusion processes and regime-switching diffusion processes in this work. For diffusion processes, some criteria based on the integrability of the functionals ... The asymptotical stability in probability is studied for diffusion processes and regime-switching diffusion processes in this work. For diffusion processes, some criteria based on the integrability of the functionals of the coefficients are given, which yield a useful comparison theorem on stability with respect to some nonlinear systems. For regime-switching diffusion processes, some criteria based on the idea of a variational formula are given. Both state-independent and state-dependent regime-switching diffusion processes are investigated in this work. These conditions are easily verified and are shown to be sharp by examples. 展开更多
关键词 stability in probability regime-switching diffusions state-dependent M-matrix
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BACKWARD STOCHASTIC VIABILITY AND RELATED PROPERTIES ON Z FOR BSDES WITH APPLICATIONS
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作者 Zhen WU Zhiyong YU 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第4期675-690,共16页
This paper investigates some important properties of Z, the martingale integrant of the backward stochastic differential equations, which is the second process of the solution. These include the backward stochastic vi... This paper investigates some important properties of Z, the martingale integrant of the backward stochastic differential equations, which is the second process of the solution. These include the backward stochastic viability property, bounded property and the comparison theorem. To explain the theoretical results, the authors apply them to study a financial contingent claim pricing problem. The replication portfolio process can be characterized clearly. 展开更多
关键词 Backward stochastic differential equations backward stochastic viability property Malliavin calculus portfolio choice.
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Contrasting Effects of Agricultural Management on Soil Organic Carbon Balance in Different Agricultural Regions of China 被引量:5
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作者 WANG Guo-Cheng LUO Zhong-Kui +1 位作者 WANG En-Li HUANG Yao 《Pedosphere》 SCIE CAS CSCD 2013年第6期717-728,共12页
Improving management of soil organic carbon(SOC)has been considered as a substantial mitigation strategy to climate change.Management such as stubble retention(SR),conservation tillage(ZT),and fertilization are recomm... Improving management of soil organic carbon(SOC)has been considered as a substantial mitigation strategy to climate change.Management such as stubble retention(SR),conservation tillage(ZT),and fertilization are recommended for both promoting production and accumulating SOC.However,whether such management practices can cause net increase in SOC or just a slow-down of SOC decline largely depends on the current status of SOC for a given region.This paper synthesized the available SOC data in the croplands of China,and analysed the change of SOC in the top 20 cm soil as a result of management change.The results showed that,on average,SOC increased by 18.3%through SR,by 9.1%through ZT,and by 12.4%,36.9%and 41.5%through application of inorganic(IF),organic(OF)and combined inorganic and organic fertilizers(IOF),respectively,compared to those under stubble removal,conventional tillage and no fertilization.Under SR,ZT,IF,OF and IOF,SOC increased by 16.0%,10.2%,8.2%,32.2%and41.3%,respectively,at the end of the trials compared with the initial values at the start of the trials.Our analysis also showed that in Northeast and Northwest China,SOC in agricultural soils is still decreasing due to cultivation.In North and South China,however,SOC appears to have reached a new equilibrium of low SOC state after a long cultivation history,and soils have greater potential to sequester C.Our analysis highlights the need of taking account of the baseline status to assess the net soil C balance over time and space. 展开更多
关键词 agricultural practices climate change FERTILIZATION residue management TILLAGE
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Qualitative analysis for a Wolbachia infection model with diffusion 被引量:7
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作者 HUANG Mu Gen YU Jian She +1 位作者 HU Lin Chao ZHENG Bo 《Science China Mathematics》 SCIE CSCD 2016年第7期1249-1266,共18页
We consider a reaction-diffusion model which describes the spatial Wolbachia spread dynamics for a mixed population of infected and uninfected mosquitoes. By using linearization method, comparison principle and Leray-... We consider a reaction-diffusion model which describes the spatial Wolbachia spread dynamics for a mixed population of infected and uninfected mosquitoes. By using linearization method, comparison principle and Leray-Schauder degree theory, we investigate the influence of diffusion on the Wolbachia infection dynamics.After identifying the system parameter regions in which diffusion alters the local stability of constant steadystates, we find sufficient conditions under which the system possesses inhomogeneous steady-states. Surprisingly,our mathematical analysis, with the help of numerical simulations, indicates that diffusion is able to lower the threshold value of the infection frequency over which Wolbachia can invade the whole population. 展开更多
关键词 dengue fever Wolbachia infection dynamics cytoplasmic incompatibility mechanism attractive region Turing instability non-constant steady-states
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Rigid Properties of Quasi-almost-Einstein Metrics
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作者 Linfeng WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2012年第5期715-736,共22页
In this paper,quasi-almost-Einstein metrics on complete manifolds are studied.Two examples are given and several formulas are established.With the help of these formulas,the author proves rigid results on compact or n... In this paper,quasi-almost-Einstein metrics on complete manifolds are studied.Two examples are given and several formulas are established.With the help of these formulas,the author proves rigid results on compact or noncompact manifolds,in which some basic tools,such as the weighted volume comparison theorem and the weak maximum principle at infinity,are used.A lower bound estimate for the scalar curvature is also obtained. 展开更多
关键词 Quasi-almost-Einstein metric Potential function Gradient estimate Rigid property
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