通辽市固日班花风电场风能储量分析

为了开发科尔沁沙地的风能资源,为其治理提供便捷、安全的能源,利用科尔沁沙地最典型地区奈曼旗固日班花风电场测风塔和奈曼气象站的风向、风速资料,对固日班花风电场的风能储量进行分析。结果表明,固日班花风电场塔高10、60、65、70、80 m处的年平均风速订正后分别为4.9、6.8、7.0、7.2、7.3 m/s;相应风功率密度分别为136.5、315.4、341.3、365.6、382.1 W/m2。逐月风速与逐月风功率密度年内变化规律基本一致。风电场风能资源较为丰富,达到了建设大型风电厂的要求。     

不同治理措施下的农田土壤风蚀控制机理研究

通过对黄羊滩沙地风速、粗糙度、防风效能、输沙量的野外观测,分析了不同治理措施下的农田土壤风蚀控制机理,研究结果表明：小网窄带防风效能高,是风沙区农田防护林合理的配置方式;此外,不同覆盖方式和不同留茬方式的地表粗糙度与秋翻裸地均是数量级的差别。在覆盖物和留茬密度基本相同的情况下,地表粗糙度和防风蚀效果均随覆盖度和留茬高度的增加而增加;在覆盖度基本相同的情况下,地表粗糙度和防风蚀效果均随覆盖物和留茬高度的增加而增加。     

Influence Factors on Wind induced Fatigue Life of Steel Circular Antenna with Asymmetric Brace

Wind induced responses of a single steel circular antenna with an asymmetric brace were computed considering wind speed and direction joint distribution function at location of the structure, and then wind induced fatigue life of the structure was estimated in frequency domain and time domain, respectively. Some parameters, including wind direction, surface roughness, vortex induced resonance and mean wind speed, which would have effects on the wind induced fatigue life of the structure,were discussed. It is found that 1) wind direction has great effects on wind induced fatigue damage, that is, significant fatigue can occur in wind direction of high probability; 2) the more roughness the surface of structure is, the shorter the wind induced fatigue life is; 3) the effects of vortex resonance on wind induced fatigue life should not be neglected; 4) the mean velocity has slight impact on the wind induced fatigue life of the structure.     

湖州大气扩散能力变化特征及其原因探讨

为大气环境治理提供理论参考,利用1980-2013年湖州大气混合层高度、大气扩散参数和平均风速等资料,分析其多时间尺度变化特征及可能原因。结果表明：(1)湖州大气混合层高度呈现缓慢增长趋势,水平风速和大气扩散参数总体趋于减弱,风速与大气扩散参数有显著的正相关关系。(2)大气混合层高度、扩散参数和水平风速的月变化呈双峰型,3月与8月为波峰,7月和10月为波谷,且三者存在显著正相关关系,其季节变化呈现春高秋低特征。(3)城市化建设、城市热岛和干岛效应等增加了大气的垂直运动能力,使得大气混合层高度增加,而地表粗糙度的增加使得水平风速减小,导致大气的水平运动能力减弱,大气扩散能力减弱。(4)紧邻太湖水体使得湖州大气扩散能力与沿海相似,水陆热力差异、风速变化、梅雨、晴热高温等对大气混合层厚度和扩散参数的季节变化都有明显影响。     

Stability Behavior of Shuttle-Shaped Steel Lattice Columns With Bending Moment

The stability behavior of shuttle-shaped steel lattice columns subject to combined axial force and bending moment was examined through elastic buckling analysis and geometrically and materially nonlinear analysis. Firstly, the concept of section stiffness variation ratio is proposed for shuttle-shaped lattice columns and the elastic buckling behavior is discussed. Then, the effect of bending moment on the stability behavior of lattice columns is investigated, with the emphasis on the development of axial stress, bending stress and shear stress. The influence of column component spacing and diaphragm thickness on the stability bearing capacity is also analyzed. It is shown that the elastic buckling mode of the lattice column is dependent on its section stiffness variation ratio; for lattice columns with C-shaped buckling mode, the reduction in stability bearing capacity caused by bending moment is smaller than that of columns with S-shaped buckling mode; the maximum stability bearing capacity of the lattice column can be achieved by adjusting the column component spacing, and the spacing corresponding to the maximum capacity is basically consistent with the critical spacing for transformation of C-shaped buckling mode and S-shaped mode; and it is more effective to increase the thickness of columns with S-shaped buckling mode to get larger bearing capacity.     

Effect of wind on the vertical circulation and stratification in the Volkerak Estuary

In the partially mixed part of the Volkerak Estuary current speed and salt concentration are measured in several stations for periods of 13 hours on August 16 and 17, 1977. The freshwater discharge on those days and during the preceding six months is kept constant at a rate of 50 m³·s⁻¹. In spite of different wind conditions, the longitudunal distribution of the tidally- and cross-sectionally averaged salt concentration is the same for both days. The vertical structure of circulation and salt concentration differ significantly. A similar set of measurements is carried out on March 18, 1980 with a constant freshwater discharge of 100 m³·s⁻¹. The doubling of freshwater discharge leads to a relatively small increase in vertical circulation and stratification.In this study, the vertical circulation and stratification is examined in terms of the external forcings, freshwater discharge and wind, with special emphasis on wind. Tide conditions, for the three measurement days are similar. The estuary is schematized to a prismatic channel with a rectangular cross-section. In the schematized channel the tidally averaged salt concentration and velocity distribution are laterally uniform. To account for salt fluxes in the actual estuary associated with lateral and time-variations in current velocity and salt concentration, a diffusive salt flux is introduced. The effect of wind and longitudinal density gradients on the vertical circulation and stratification in the schematized channel is investigated using a simplified form of the two-dimensional conservation of momentum and salt equations. Using observed values along the axis of the estuary a scaling analysis shows that in the two-dimensional conservation of momentum equation the longitudinal pressure gradient and horizontal turbulent shear are the dominant terms, closely followed by the tidal stress. In the conservation of salt equation, the dominant terms are those associated with advective fluxes resulting from the horizontal and vertical tidal mean velocities, a horizontal flux associated with tidal variations in the longitudinal velocity and salt concentration and the vertical turbulent flux. Retaining only first order terms, the equations are solved using the similarity solution of Hansen and Rattray. Comparing calculated and observed vertical circulation and stratification it is shown that wind mixing significantly increases the vertical exchange of momentum, thereby reducing the density-driven vertical circulation (=gravitational circulation) and stratification. At the same time, through the wind surface stress, wind generates its own vertical circulation and, therefore, stratification. An expected increase in vertical exchange of mass with increasing wind speed and accompanying reduction in stratification could not be confirmed by the analysis. It is concluded that on the days of the measurements wind is as important as the longitudinal salt concentration gradient in forcing vertical circulation and stratification. Care should be taken in generalizing this conclusion as on the days of the measurements the axial component of the wind velocity is always in the down estuary direction.     

海南省不同区域农业可持续发展评价研究

为准确把握海南省典型地区农业可持续发展状况,诊断识别各地区农业可持续发展的障碍性因子,通过基于欧氏距离的农业可持续发展评价理论对海南省农业可持续发展情况进行评价。选取海南省海口市、三亚市和琼中县的2000~2015年数据展开分析,结果表明：(1)海口市农业可持续发展指数总体变化呈下降趋势,可持续发展指数介于0.44~0.52;三亚市农业可持续发展指数呈现上升趋势,可持续发展指数处于0.31~0.59之间;琼中县农业可持续发展指数呈上升趋势,但2007年之后可持续发展指数呈波动发展,可持续发展指数处于0.27~0.31之间。三个地区均属于低可持续发展状态。(2)肥料、农药、农村灾害、农技和农村劳力等指标是海南省低可持续发展的主要原因。各地区应该因地制宜,制定符合自身情况的政策和方针。(3)评价结果较为准确地反映了海南省农业系统情况。在上述研究结果基础上,研究其时空变化特征,提出未来推动该地区农业可持续发展举措,以期为海南省农业可持续发展提供参考。     

菏泽市农村低碳社区可循环再生资源评估

笔者报告了菏泽市农村社区建设中的可循环资源量,并对低碳社区提出了建议,得出结论与建议：（1）菏泽市每年能够为农村社区提供稳定的太阳辐射能源5388.9 MJ/m2,将农村社区太阳能开发可利用系数设定为0.3,那么一个在建10000 m2的低碳农村社区可开发的太阳能源储量为：1.62×106 MJ,减碳潜力折合为标准煤55 t,适合太阳能应用的主要设施为太阳能光伏、光热设备。（2）10、30、50、80 m高度能够提供的风功率密度分别为12、21、56、75 W/m2,风功率密度都属于1 级,因此,菏泽农村社区建设过程中风能源不建议大规模开发,需考虑特殊地形后合理设计开发,或者采用风光互补路灯等新能源设备。（3）菏泽年平均降水量621.4 mm,年平均降水日数73.2 天,平均降水强度为8.5 mm/d,在农村社区建设过程中雨量收集利用价值明显,农村社区的雨量径流系数为0.4~0.5,流量径流系数为0.5~0.6,菏泽市农村建设用地多为黏土性质,渗透系数<5.7×10-8。     

Experimental Analysis of Extension Length of Shape Steel in SRC-RC Transfer Column

Seismic performance of SRC-RC transfer column was analyzed based on experiment of 12 specimens of transfer columns and 1 RC specimen under low cyclic reversed loading, which mainly focused on the extension length of shape steel. Analysis and comparison on skeleton curves of specimens was carried out. Analysis was completed for ductility, bearing capacity, energy dissipation capacity and degeneration ratio of strength. Displacement ductility changes with the increase of extension length of shape steel, enhancing at first, then reducing, and reaching peak value when extension length is close to three fifths of column height. Extension length of shape steel has little effect on bearing capacity. Energy dissipation capacity of transfer columns has relationship with many factors. Three fifths of column height is rational for extension length of shape steel, and specimens have not only advanced performance of energy dissipation but also good stability of stiffness and strength in this condition. The bond performance between concrete and shape steel decreases with the increment of extension length of shape steel, and hence stability of strength decreases.     

Research on Index of Reliability for Bearing Capacity of Rock - Socketed Single Pile in Chongqing

Based on the data from in-situ 102 rock-socketed test piles in Chongqing in recent 10 years and utilizing the limit state equation of the dimensionless random variables,the reliability analysis of the bearing capacity of rock-socketed single pile is made and the scope of the target reliability of rock-socketed piles in Chongqing is calculated with both JC method and Monte-Carlo method respectively.Furthermore,the target index of reliability is suggested.Finally,the concept of reliability coefficient(to replace the load partial factor and the resistance partial factor) is given and the bearing capacity of the single pile is determined by utilizing optimization method.Besides,the practical limit state design equation using reliability coefficient is put forward for its advantage of incarnating the simple and practical principle and being easy mastered and understood by the designers.     

科尔沁沙地4种作物根茬抗风蚀效果风洞试验研究

摘 要：利用野外风洞设备,以翻耕地为对照,对科尔沁沙地东部农田的4种不同作物茬地抗风蚀效果进行了测试,对风蚀主要影响因子进行了分析。试验结果表明：作物留茬可显著提高地表抗风蚀能力;在相同风速条件下,抗风蚀能力大小依次为燕麦茬地>玉米茬地>向日葵茬地>绿豆茬地>翻耕地;与翻耕地相比,燕麦茬地、玉米茬地、向日葵茬地和绿豆茬地的起动风速分别抬高了53.3% 、17.8% 、11.1%、 8.9%。本试验表明,风蚀量与土壤地表覆盖度、土壤0～5cm表层含水量、地表粗糙度、土壤容重、土壤坚实度呈负相关关系,其中与前三者呈显著高度负相关关系。采用免耕留茬措施可以有效地抑制农田土壤风蚀,有利于防治农田荒漠化。     

张家口地区风特征分析

为了揭示张家口地区风向风速时空分布特征及主要变化趋势,为该地区合理利用风资源、减轻风灾提供参考,利用1960—2013年张家口地区14个气象站风速风向观测资料,借助数理统计、线性拟合、气候倾向率等方法,对该区域的风特征进行了统计分析。结果表明,张家口地区年均风速坝上地区为3.6~4.1m/s,大于坝下地区的1.8~3.0m/s。年均风速变化总体呈减小趋势,54年间坝上与坝下地区分别减小了2.21m/s与0.92m/s,最大减小幅度均出现在20世纪70年代。年均风速呈“春季大、夏季小”的分布类型,平均风速最大、最小值分别出现在4月和8月。年均风速冬季减小速率最大,夏季最小。风速日变化坝上地区13—15时、坝下地区15时左右达到最大,凌晨5—7时风速最小,一天中平均风速上午的增长率与午后的下降率,坝上地区均大于坝下地区。坝上四县年均大风日数为48.5天/县,坝下为31.8天/县,大风日高值时段发生在1963—1974年间,坝上与坝下地区大风日数分别以9.4d/10a与7.1d/10a的速率减少。张家口地区全年以NW、偏北和偏西风向为主,市区、各县春季和冬季主导风向一致,夏季和秋季主导风向一致;进入夏季,随着暖湿气流的增强,张家口市偏南和偏东风出现频率有所增加。     

临汾市雾霾天气的分析和研究

为了进一步提高对临汾市雾霾的预测以及防治效果,从而避免、减轻雾霾天气对人类造成的交通、健康等危害。根据临汾市2013年11月—2014年3月自动气象站对PM_1.0、PM_2.5、PM₁₀、能见度、相对湿度、气温等的观测资料,利用临汾市1954—2014年12—3月的降水日数和静风日数的统计资料,利用数理统计、线性拟合、多元回归等方法,分析临汾市秋冬季雾霾与天气气象要素之间的关联。结果表明：风速、气压、气温都会对空气的能见度产生影响,其中风速的影响最大,风速每增大1 m/s,能见度增加3.3 km;气温、相对湿度、风速、能见度均与PM_2.5呈负相关,风速与PM_2.5浓度值的负相关程度最大,风速每增大1 m/s,PM_2.5的浓度值减少65.2 μg/m³;静风日数以0.98 d/10 a的速率减少,而降水日数以 0.07d /10 a的速率减少。     

Gear-bearing coupling dynamics characteristics of wind turbine planetary gear transmission system under variable load

Considering that the transmission system of wind turbine works in complex and changing load environment caused by stochastic wind speed,this paper uses sparse least squares support vector machine(SL-SVM) to simulate wind speed of true wind field,and obtains time-varying wind load caused by stochastic wind speed. The lumped-parameter method is used to develop a dynamic model of planetary gear transmission system of wind turbine coupled with bearing. The model includes the varying wind load,time-vary mesh stiffness of gear pair and time-vary stiffness of rolling element bearing. The numerical method is used to simulate the dynamic performance of planetary gear system of Multibrid Technology Wind Turbine with 1.5 MW rated power. The vibration displacement responses of the transmission system are obtained as well as dynamic meshing force each pair of gear and nonlinear bearing forces. The research can provide a foundation for optimizing dynamic performance and reliable design of gear transmission system of wind generator.     

基于混合效应的湖北杉木冠长率模型

为研究冠长率与林分因子之间的生长关系,分析不同因素对冠长率的影响,对湖北全省杉木栽植区域进行标准地调查,利用181块调查样地的715株优势木和平均木数据建立冠长率模型.从树木及立地因子中选出与冠长率相关性显著的树高、胸径、高径比、每公顷株数和大于对象木断面积5个因子作为变量,利用Logistics方程构建冠长率基础模型...     

风廓线雷达资料在沈阳冰雹天气过程中的分析应用

本文利用风廓线雷达的基本产品、Micaps实况资料和区域自动站资料,对沈阳城区发生的一次冰雹天气过程进行分析,结果表明：此次冰雹是在冷涡背景下,高空存在横槽、逆温,触发的局地的强对流天气过程。降雹前高空由西北风转为偏西风,预示着横槽的到来,风廓线雷达对冷空气侵入的判别提前于常规观测资料。1000 m以下水平风的变化与降雹时间及强度有较好的对应。高空水平风速≥12 m/s的风速带在降雹前1h达到峰值。高空急流区在冰雹发生前20~25min出现急流动量下传,为冰雹的产生提供动力条件。降雹阶段探测高度明显增加,主要是由于空气湿度增大和高层存在大量冰晶粒子所致。冰雹过程中,冰晶粒子主要集中在1900 m以下。降雹前25min垂直风切变增大,并在降雹前20min达到极值,垂直风切变的变化与急流的变化相对应。垂直速度达到极值对应的并不是降雹的开始,低层信噪比＞60 dB,对应降雹开始,信噪比对于冰雹的敏感程度比垂直速度高。垂直速度大于4 m/s与降水的开始、结束时间有着很好的对应关系。     

华贵栉孔扇贝不同壳色后代早期发育阶段性状比较

为了提高华贵栉孔扇贝的产量以及通过人工选择培育新品种,利用同一养殖群体中的橙色、褐色、橙褐色个体为亲本,采用个体间随即交配的方法,于2008年10月14日、16日和18日分批建立了橙色、褐色、橙褐色三个不同群体。为了减少环境效应,自受精卵孵化开始,三个群体一直被培养在相同的环境条件下。结果发现,三个群体在受精卵孵化率、幼虫存活率、幼虫及稚贝生长等方面都存在显著差异。就孵化率而言,橙色的最高、褐色的次之、橙褐色的最低,分别为97.5%、92.6%和91.3%;就幼虫存活率而言,橙褐色的最高、褐色的次之、橙色的最低,10日龄时分别为67.0%、43.8%和16.0%;就幼虫期生长而言,褐色生长最快、橙褐色次之、橙色生长最慢,壳长的日增量分别为9.49μm、8.30μm和7.73μm,壳高的日增量分别为8.18μm、7.17μm和6.61μm,且壳长比壳高生长得快;就稚贝期生长而言,橙褐色生长最快、橙色次之、褐色生长最慢,壳长的日增量分别为64.6μm、58.6μm和49.0μm,壳高的日增量分别为78.6μm、70.5μm和59.5μm,但壳高比壳常生长得快。很明显,华贵栉孔扇贝的壳色与其生长、存活有密切的联系,这为其选择育种提供了理论依据。     

Experimental Analysis of the Behavior of Steel Plate-masonry Composite Wall-beams

When steel plate-masonry composite structure used in the existing masonry structure with load bearing walls is removed for a large space, composite action should be considered between the beam and the supported masonry wall due to the arch effect formed in the supported wall. In order to investigate the working mechanism, failure mode, and load-carrying capacity, strain distribution in critical sections and mid-span defcection of this type of composite wall-beam, five steel plate-masonry wall-beams were tested under concentrated loads and analyzed, which considered variables of height-span-ratio of supported masonry wall, height-span-ratio of composite beam and thickness of steel plate. The results show that steel plate-masonry composite wall-beam starts failure from the masonry located at the line between loading point and supporting point; strain distribution of steel plate along section height meets the plane section assumption; the height-span-ratio of supported wall can directly influence the failure mode of masonry wall, buckling load corresponding to steel plate experiencing local buckling and ultimate load of tested specimens; the reasonable height of supported masonry wall is beneficial to the formation of composite action between supported masonry wall and composite beam, and the excessive high masonry wall will reduce the ultimate load of the tested specimen. Finally, the reasonable range for height-span-ratio of supported masonry wall was presented, and the proposed value representing the flexural stiffness of the steel plate-composite beam relative to the in-plane stiffness of the supported masonry wall was at least more than 79.     

Sub-tidal dynamics of a near-coastal zone in the north sea

Data, gathered in the North Sea some 60 km north of the Netherlands, are used to describe the regional dynamics at sub-tidal frequencies. Using a tidally averaged set of the vertically averaged horizontal momentum equations, the influence of the separate terms in these equations is investigated experimentally. The results reveal that, especially further offshore, the wind driven motion is in (near) geostrophic balance. This confirms the ability to monitor the circulation, using information on the wind field and the bottom pressure distribution, within an accuracy equivalent to an accuracy of 0.5 mb of low pass filtered bottom pressure gauge measurements.In a part of the area where the bottom topography reaches a slope of 1.2×10⁻³ and where density fronts are observed, the motion is frequently found out of geostrophic balance. The apparent imbalance can partly be attributed to ‘sub-grid’ horizontal density gradients, which are incorporated in the measured bottom pressure gradients, assuming that no sea-level adjustment occurs.     

雄安新区气候特征及变化趋势分析

为了更好地为雄安新区的规划和建设提供气候服务,本文以雄安新区3个国家气象站建站至2018年的逐日气象观测资料,系统分析了雄安新区的基本气候特征及其变化趋势;并采用2009—2018年精细化陆面同化数据和气候变化预估数据,分析了雄安新区最近10年以及未来10年降水量和气温的空间分布特征。结果表明：雄安新区平均年降水量480.8 mm,降水集中在6—9月;1961—2018年,雄安新区平均年降水量总体呈减少趋势,其中夏季减少趋势明显,而秋季增多趋势较为明显;预计未来10年,雄安新区大部分地区降水量增加。雄安新区年平均气温、平均最高气温和平均最低气温分别为12.6、18.7、7.3℃,年内（1981—2010年平均）,雄安新区7月份气温最高,1月份最低;1961—2018年,雄安新区平均气温、平均最高气温和平均最低气温总体均呈升高趋势,其中春季和冬季升温明显,其次为夏季,而秋季气温变化趋势不明显;预计未来10年,雄安新区气温将明显上升。雄安新区年平均日照时数2335.2 h,年内,春、夏季日照时数相对较多,秋、冬季日照时数相对较少;1968—2018年,雄安新区年日照时数总体呈减少趋势,其中秋季减少速率最快,春季相对最慢。雄安新区年平均风速1.7 m/s,年内,4月平均风速最大,1、8、12月相对最小;1961—2018年,雄安新区年平均风速总体呈减小趋势,其中冬季减小速率相对最大,夏季最小。