Research on Allocation of Production Factors and Income Disparity in Urban-Rural of China

改革开放30年，中国经济的发展取得了举世瞩目的成就，人民的生活水平也得到了迅速的提高。但是在经济持续快速增长的同时，城乡之间、地区之间、行业之间的收入分配差距却呈现扩大的趋势，这已成为影响我国社会稳定和经济发展的重要问题，其中又以城乡居民收入差距的问题尤为突出。本文针对这一现象，从理论和实证的角度出发，以市场经济下生产要素城乡间的不同配置为视角，对引起我国城乡居民收入差距变动的影响因素进行了探讨。 1978年以来，我国的改革方向是从垄断式、单一的计划经济体制到以自由竞争为特征的市场经济体制转变，相应的，在收入分配领域也随之经历了从单一的按劳分配，到按劳分配与按生产要素分配相结合的演变过程。按...Due to the 30’s reform and opening, the Chinese economy has been developed greatly, and the living conditions of Chinese also improved rapidly. But in the meantime, the income disparity of urban-rural, different region and different industry is getting serious. Especially the income disparity in urban-rural has been an important factor which can influence the social stability and economy developme...学位：经济学硕士院系专业：经济学院经济系_政治经济学学号：1532006115076

Ship formation control via output feedback with unknown dynamics

研究了仅利用相对位置信息和相对航向信息的船舶编队输出反馈控制问题.首先使用leader-follower策略,建立了船舶编队的运动学模型.然后应; 用微分同胚变换将系统解耦成3个子系统.根据船舶低频运动的特点,在跟随船水动力学模型中粘性水动力和力矩未知以及所有船舶速度都不可测量的假定下,提出; 了一种高增益广义比例积分观测器来估计这些未知和不可测量动态.在高增益广义比例积分观测器的基础上,分别设计了线性输出反馈控制器和输入饱和受限的输出; 反馈控制器,并分析了闭环系统的稳定性.最后仿真结果表明了方法的有效性.This paper focuses on the ship formation control problem via output; feedback, with only the information of the relative positions and; relative heading angles available. Firstly, the kinematic model of the; ship formation is established using the leader-follower strategy. Then; the system is decoupled into three subsystems via the diffeomorphism; transformation. According to the low frequency characteristics of the; ship motion, and the assumption that the viscous hydrodynamic forces and; moments in the hydrodynamic models of the follower ships are unknown and; the velocities of all the ships are unmeasurable, the high-gain; generalized proportion-integral observers are proposed to estimate the; unknown and unmeasurable dynamics. On the basis of the high-gain; generalized proportion-integral observers, the linear output feedback; controllers and the output feedback controllers with input saturation; are designed respectively, and the stability of the closed-loop systems; is analyzed. Finally, the simulation results show the effectiveness of; the proposed approach.国家自然科学基金项目; 福建省自然科学基金项

塑造文化传统：华安高山族的舞蹈实践

20世纪90年代以来,高山族舞蹈逐渐被塑造为华安高山族的文化传统。其背后透露出华安高山族、文化权威及地方政府构成的权力关系,在政治经济脉络下,促使舞蹈成为一种社会记忆被标签化,也使高山族人对本民族文化呈现出多重认同感。国家社会科学基金重大项目“台湾原住民族群关系研究”（14ZDB113

认同、想象与表达:华安高山族的文化重构

华安县是大陆高山族同胞聚居最多的县份,而华安高山族在近几十年的生活中经历了在地化的过程.20世纪90年代初,地方社会政治、经济发展为高山族文化重构奠定良好基础,高山族文化逐渐获得发展,产生了以舞蹈和服饰为主的文化内容.高山族以集体或个体不同形象主动参与文化重构,其主体性意识逐渐提升,不断加强了身份认同与文化认同.国家社会科学基金重大项目“台湾原住民族群关系研究”(14ZDB113)阶段研究成

THE ECOLOGICAL SECONDARY XYLEM ANATOMY OF THE MANGROVE AEGICERAS CORNICULATUM AND SONNERATIA CASEOLARIS

对紫金牛科 (Myrsinaceae)的桐花树 (Aegicerascorniculatum)和海桑科 (Sonneratiaceae)的海桑 (Son neratiacaseolaris)的次生木质部的组织结构和数量特征进行了研究 ;并讨论了桐花树和海桑的木材结构与环境关系 ;它们的导管直径小、导管数量多、导管分布频率高 ,是对海滨盐渍环境的适应 ,保证水分在植物体内运输的安全性。桐花树和海桑的纤维壁厚度 (W )与纤维腔宽度 (L)的比值 (2W /L)分别为 0 6 7和 0 4 5 ,均小于 1 ,从木纤维 2W /L <1的角度看 ,桐花树和海桑的木材可用作造纸原料This paper deals with the morphological and quantitative characters of secondary xylem of Aegiceras corniculatum and Sonneratia caseolaris . The relation between the structure of wood and the environmental influences has also been discussed.The features of small vessel diameter,many vessel numbers and high vessel frequency ensure the safety for water transportation inside plant.The ratios (2W/L), namely thickness of fiber wall (W) and width of fiber cavity (L), of both Aegiceras corniculatum (0.67)and Sonneratia caseolaris(0.45) are less than 1,demonstrating their timbers are the good raw materials for papers making.国家自然科学基金!项目 (批准号 495 762 95

多艘拖轮协助大型船舶靠泊的编队控制方法

为了研究多艘拖轮协助欠驱动大型船舶靠泊的控制,提出了一种采用拖轮编队来解决大型船舶靠泊问题的控制方法.在拖轮的水动力学模型中,将大型船舶对拖轮的反作用力视为未知输入,给出了一种干扰估计误差方程和原状态方程形成互联系统的干扰观测器.该干扰观测器使得拖轮速度实际值与期望值误差能够快速收敛.在干扰观测器的基础上给出了拖轮编队控制器设计,并分析了闭环系统的稳定性.仿真结果验证了该方法的有效性.国家自然科学基金(61374037

临床实验室体液样本库建设

生物样本库是临床医学、基础医学和转化医学研究的基石和重要推动力。临床实验室(检验科)以血液等体液为日常检测对象,拥有丰富的体液标本资源,在体液样本库建设中具有显著优势。临床实验室应推进生物样本库标准操作规程文件撰写,标准化、规范化建设体液样本库,以促进医学检验学科的科研、教学的发展。国家自然科学基金(81101331;81472031

电学开路挠曲电悬臂梁自振频率分析

挠曲电效应是一种新兴的机电耦合效应,在微纳米尺度的传感器、致动器和俘能器方面有广阔的应用前景.本文基于挠曲电材料的变分原理和电吉布斯自由能,推导了表面覆盖电极的挠曲电悬臂梁在电学开路条件下的机电耦合动力学控制方程和相应的力电边界条件.进一步获得了求解电学开路条件下挠曲电悬臂梁自振频率的超越方程.以聚偏氟乙烯(PVDF)材料为算例,讨论了挠曲电系数、末端质量块和梁尺寸对结构自振频率和电学开路/短路条件下结构自振频率有效频移的影响.计算结果表明,挠曲电系数的增大会提高梁的自振频率;末端质量的增大可以降低梁的自振频率,并且末端质量块的转动效应对悬臂梁自振频率的影响很小;悬臂梁结构的有效频移随着结构尺寸减小而增加,并在某一厚度尺寸趋于饱和值.国家自然科学基金(11572271

Sapflow characteristics of Kandelia obovata and their controlling factors in Zhangjiang estuary,China

利用Granier热消散式探针法对福建漳江口国家级红树林自然保护区内红树植物秋茄的树干茎流密度(SFD)进行1年(2010年10月至2011年10月)的连续监测.结果表明:季节和树干径级对秋茄树干茎流密度均有显著影响.在夏季,胸径(DBH)为8~10 cm时秋茄树干最外层2 cm处的SFD达到最大,为38.21 g·m~(-2)·s~(-1),这与其他红树物种以及湿地乔木物种的茎流密度相当.不同径级(小、中、大径级分别为2~4、4~8、8~10 cm)秋茄每日整树蒸腾量(即水分日利用量)也呈现明显的季节变化,从冬季到夏季的波动值分别为0.14~0.19、0.94~1.45、1.96~3.43 kg·d~(-1).通过整合各个径级秋茄树的日蒸腾量推算得到秋茄林的日蒸腾量,再全年累加计算得到秋茄林年总蒸腾量为100.38 mm,不到当地年降水量的6%.主要环境因子对秋茄林蒸腾速率(E_s)均有极显著影响(P<0.001),其中,光合有效辐射(PAR)和饱和水汽压差(VPD)是E_s最主要的驱动因子,解释了E_s60%~92%的季节变异,且夏季秋茄E_s对PAR和VPD的依赖性大于冬季.秋茄E_s与环境因子之间存在明显的时滞现象,需要在解释秋茄林E_s季节变异时加以考虑.In this study,the Grainer's thermal dissipation probe method was applied to monitor sap flux density( SFD) of a mangrove species Kandelia obovata over a period of one year( 2010-10—2011-10) in Zhangjiangkou Mangrove National Nature Reserve,Fujian,China. The results showed that both season and diameter class exerted significant effects on the SFD of K. obovata trees. In summer,when the diameter at breast height( DBH) reached 8-10 cm,the highest SFD was found at a depth of 2 cm with a value of 38.21 g·m~(-2)·s-1,which was comparable with those for other mangrove tree species and forested wetland tree species. The mean whole tree transpiration( i. e.daily water use) of all stem size classes demonstrated large changes from winter to summer,increased from 0.14 to 0.19 kg·d~(-1)in small trees( S,DBH = 2-4 cm),from 0.94 to 1.45 kg·d~(-1)in medium trees( M,DBH = 4-8 cm) and from 1.96 to 3.43 kg·d~(-1)in large ones( L,DBH = 8-10 cm). The daily transpiration of K. obovata stand was calculated by summing all size classes,which was then summed up for entire year to estimate annual transpiration of entire K. obovata forest,which was about 100. 38 mm,less than 6% of local annual precipitation. Key environmental factors all had significant effects( all P<0.001) on the stand transpiration rate( E_s) of K. obovata forest,and photosynthetically active radiation( PAR) and vapor pressure deficit( VPD) were themain driving factors,which explained 60%-92% seasonal variation of E_s. The PAR and VPD had larger effects on the E_sin summer than that in winter. In addition,we observed an obvious time lag phenomenon in the relationship between E_sand PAR or VPD,which should be taken into account when explaining seasonal variation of E_sin K. obovata forest.国家自然科学基金项目(30930017);; 国家海洋局海洋公益性行业科研专项(201305021)资助~

Seedling emergence and dispersal pattern of the introduced Sonneratia caseolaris in Shenzhen Bay, China

海桑(Sonneratia caseolaris)是我国华南沿海主要红树林造林树种,在深圳湾引种造林15年后,在天然红树林和光滩中出现了大面积的扩散。为了研究深圳湾红树植物海桑的幼苗扩散及其与生态因子的关系,作者采用样线和样方调查法于2006年9月至2007年9月对深圳福田红树林内天然扩散的海桑幼苗的密度、高度和盖度及其相关生态因子(包括种间竞争、群落类型、光照、扩散距离与滩面高程)进行了6次调查。天然红树林和人工海桑林林下海桑幼苗密度在调查初期分别为24.7棵/m2和19.7棵/m2,到2007年9月林下的一年生海桑幼苗全部死亡,说明林下的弱光生境显著抑制了海桑幼苗的早期生长和自然更新。不同林型下(包括天然白骨壤林和秋茄林、人工海桑林)的海桑幼苗的密度、高度、盖度差异不显著(P>0.05);而林中空地各指标显著高于林下(P0.05),而人工海桑林林下的海桑幼苗密度与光照强度呈显著正相关,且相关系数逐次增大,说明海桑幼苗的早期生长受到光照强度的影响极为显著。因此,深圳湾引种海桑的繁殖体在天然白骨壤林和秋茄林下的扩散主要受与母树距离的影响,但在海桑人工林下光照强度是影响幼苗分布的最重要生态因子。Due to its rapid growth, Sonneratia caseolaris, a mangrove species indigenous to Hainan, was introduced to Shenzhen Bay, Guangdong for afforestation purpose during the early 1990s. The seedling emergence, early growth and dispersal pattern of S. caseolaris and their responses to environmental factors have not been well studied in the new habitat. In this study, we evaluated the density, height and coverage of S. caseolaris seedlings underneath the canopies of various mangrove forests (including both natural Kandelia candel and Avicennia marina communities and introduced S. caseolaris communities) and on the mudflats without canopy, in Futian Mangroves Natural Reserve of Shenzhen Bay from September 2006 to September 2007. Line intercept and square intercept methods were used in the survey. Tidal elevation, light intensity, community types and the distance between the sample squares and the nearest adult S. caseolaris were also recorded. The mean densities of S. caseolaris seedlings under the canopies of both the introduced and natural mangrove forests decreased from September 2006 (24.7 seedlings per m2 and 19.7 seedlings per m2 , respectively) to September 2007 (no seedlings survived). No significant differences were found in the seedling density, height or coverage of S. caseolaris among different mangrove communities. However, the density, height and coverage of S. caseolaris seedlings were significantly higher on the mudflats without canopy than under the mangrove canopies, indicating that higher light intensity in on the mudflats without canopy promoted the dispersal and vertical growth of S. caseolaris seedlings. Although the optimal tidal elevation for S. caseolaris seedlings in Shenzhen Bay was between 1.40 m and 1.60 m, an area that falls within the mid-to-high intertidal zones, seedling density and tidal elevation were weakly correlated. The seedling density under the native mangrove canopies was negatively related to dispersal distance. However seedling density were positively correlated with light intensity(P<0.05), and the correlation coefficients for the introduced S. caseolaris forest increased through time with successive surveys. In contrast, there was no significant correlation founded between seedling density and light intensity under native mangrove canopies. We concluded that distance to mother tree was the most important factor determining S. caseolaris seedling density under native mangrove canopies, whereas the light intensity was the most important environmental factor for controlling seedling dispersal pattern under the canopy of the introduced S. caseolaris forest.中国科学院“百人计划”资助项目;; 国家自然科学基金(30700092);; 中国博士后科学基金(20060400529