黑龙江垦区企业综合评价模型及结果

介绍了离差平方和最大化决策法和均方差决策法两种综合评价方法,并利用这两种评价方法对黑龙江垦区8个大型企业和9个农场分局2009年度的经营绩效情况进行了综合评价.     

Viking bistatic radar observations of the hellas basin on Mars: preliminary results

Preliminary reduction of Viking bistatic radar data gives root-mean-square surface slopes in the Hellas basin on Mars of about 4 degrees on horizontal scales averaged over 10 centimeters to 100 meters. This roughness decreases slightly with position along the ground track, south to north. The dielectric constant in this area appears to be approximately 3.1, greater than the martian average. These values are characteristic of lunar maria and are similar to those found near the Viking lander site in Chryse with the use of Earth-based radar.     

Lateral diffusion of visual pigment in photorecptor disk membranes

Visual pigment molecules are found to move transversely, but not longitudinally, in both rod and cone outer segments of mud puppy and frog. This is consistent with the idea that they are immersed in a two-dimensional fluid disk membrane. The diffusion coefficient for the motion is about 5 x 10(-9) square centimeters per second at 20 degrees C, corresponding to a root-mean-square molecular displacement of 0.3 micrometer in 1 second.     

Polar motion measurements: subdecimeter accuracy verified by intercomparison

An important bound on the accuracy of modern techniques for monitoring polar motion is established by intercomparison of measurement series from two different observing techniques, very long baseline interferometry and satellite laser ranging. The root-mean-square differences between the estimates of the pole position from both techniques are shown to be only 2 milliseconds of arc (about 6 centimeters at one Earth radius). In the absence of common systematic errors, these differences bound the total errors in both sets of estimates. An initial investigation did not reveal any clear signature in the pole position that seems to be associated with major earthquakes. Continued measurements at this level of accuracy hold promise for resolving long-standing arguments over such questions as the nature of the excitation mechanism required to maintain the motion of the pole.     

基于有机元素含量的猪粪热值预测模型

探讨利用猪粪有机元素含量预测猪粪热值的可行性,建立基于C、H、N、S、O等5种有机元素含量的高、低位热值预测模型.采集了160个猪粪样品,利用EA3000型元素分析仪和IKA-C2000型氧弹量热仪分别测定其C、H、N、S、O元素的含量和高、低位热值.相关分析表明,C、H、N这3种元素的含量与热值之间存在极显著相关,而S、O这2种元素含量与热值之间的相关不显著;利用120个猪粪样品的测定结果,采用多元线性回归分析建立的基于C、H、N含量的热值预测模型可以较准确地利用碳、氢、氮预测猪粪热值,高位热值和低位热值预测模型的决定系数R2分别为0.836和0.785.用40个样品对热值模型进行外部验证,高位热值和低位热值均方根误差RMSE分别为621.31、620.85 J/g,相对均方根误差RRMSE分别为3.74％和4.06％.结果表明,多元线性回归法建立的基于有机元素含量的猪粪热值预测模型的预测结果较准确,利用猪粪的元素含量预测其热值是可行的.     

Lidar observations of the meteoric deposition of mesospheric metals

The mesospheric sodium and iron layers at an altitude between about 80 and 110 kilometers are routinely monitored by atmospheric physicists using resonance fluorescence lidar techniques because these constituents are excellent tracers of mesopause chemistry and dynamics. The mesospheric metals are the products of meteoric ablation. Existing ablation profiles are model calculations based in part on radar observations of the ionized background atmosphere left in the wake of high-speed (> 20 kilometers per second) meteoroids. Thin trails of neutral metal atoms, ablated from individual meteoroids, are occasionally observed with high-power lidars. The vertical distribution of 101 sodium and 5 iron meteor trails observed during the past 4 years at Urbana, Illinois; Arecibo, Puerto Rico; and near Hawaii is approximately Gaussian in shape with a centroid height of 89.0 (+/- 0.3) kilometers and a root-mean-square width of 3.3 (+/- 0.2) kilometers. This directly measured ablation profile is nearly the same as the mean iron layer profile but is considerably different from existing models and the distribution of ionized meteor trails observed by radars. A lower limit on the influx to the mesopause region from the lidar meteors is approximately 1.6 x 10(3) sodium and 2.7 x 10(4) iron atoms per second per square centimeter, which corresponds to an annual flux of meteoric debris into the mesosphere of about 2.0 (+/-0.6) gigagrams. Because the lidars can detect only the ablation trails left by the larger meteors, the observations suggest that the actual meteoric influx may be larger than the more recently reported values, which range between 16 and 78 gigagrams per year.     

Ocean Tides for and from TOPEX/POSEIDON

Comparisons of TOPEX/POSEIDON tidal solutions derived from the data of the first year of this altimetric mission with the best previous models and with in situ data show very substantial improvements. Typically, the gain in accuracy for the major lunar tidal component M(2) is 30 percent in root-mean-square differences with reference to a standard ground truth data set from 78 stations distributed over the world ocean. This is a major step, obtained because of the high quality of these altimetric data. The combination of these data with recent numerical models through assimilation methods is pointing toward solutions at the ultimate limits of practical accuracy.     

消除偏差集合平均在黄海渤海大风预报中的应用

基于日本气象厅预报模式（JMA）、美国国家环境预报中心预报模式（NCEP GFS）及美国海军全球大气预报谱模式（NOGAPS）3个模式2009年6月28日~8月10日每日20：00预报的海面风场预报资料,利用消除偏差集合平均对海面风场进行预报试验,并采用均方根误差对预报结果进行检验评估。结果表明,对于24、48 h海面风场预报,消除偏差集合平均有效地减小了预报的均方根误差,预报效果优于单个模式的预报;其中,渤海中部偏南地区及黄海中部误差减小最为明显。此外,消除偏差集合平均预报明显改善了2009年7月13~14日和8月7日大风过程的预报效果,提高了风速值和大风区位置的预报准确率。     

Solution of a protein crystal structure with a model obtained from NMR interproton distance restraints

Model calculations were performed to test the possibility of solving crystal structures of proteins by Patterson search techniques with three-dimensional structures obtained from nuclear magnetic resonance (NMR) interproton distance restraints. Structures for crambin obtained from simulated NMR data were used as the test system; the root-mean-square deviations of the NMR structures from the x-ray structure were 1.5 to 2.2 A for backbone atoms and 2.0 to 2.8 A for side-chain atoms. Patterson searches were made to determine the orientation and position of the NMR structures in the unit cell. The correct solution was obtained by comparing the rotation function results of several of the NMR structures and the average structure derived from them. Conventional refinement techniques reduced the R factor from 0.43 at 4 A resolution to 0.27 at 2 A resolution without inclusion of water molecules. The partially refined structure has root-mean-square backbone and side-chain atom deviations from the x-ray structure of 0.5 and 1.3 A, respectively.     

Florida current volume transports from voltage measurements

The volume transport of the Florida Current is determined from the motionally induced voltage difference between Florida and Grand Bahama Island. Simultaneous measurements of potential differences and of volume transport by velocity profiling have a correlation of 0.97. The calibration factor is 25+/- 0.7 sverdrups per volt, and the root-mean-square discrepancy is 0.7 sverdrup. The induced voltage is about one-half the open-circuit value, implying that the conductance of the sediments and lithosphere is about equal to that of the water column.     

A novel, highly stable fold of the immunoglobulin binding domain of streptococcal protein G

The high-resolution three-dimensional structure of a single immunoglobulin binding domain (B1, which comprises 56 residues including the NH2-terminal Met) of protein G from group G Streptococcus has been determined in solution by nuclear magnetic resonance spectroscopy on the basis of 1058 experimental restraints. The average atomic root-mean-square distribution about the mean coordinate positions is 0.27 angstrom (A) for the backbone atoms, 0.65 A for all atoms, and 0.39 A for atoms excluding disordered surface side chains. The structure has no disulfide bridges and is composed of a four-stranded beta sheet, on top of which lies a long helix. The central two strands (beta 1 and beta 4), comprising the NH2- and COOH-termini, are parallel, and the outer two strands (beta 2 and beta 3) are connected by the helix in a +3x crossover. This novel topology (-1, +3x, -1), coupled with an extensive hydrogen-bonding network and a tightly packed and buried hydrophobic core, is probably responsible for the extreme thermal stability of this small domain (reversible melting at 87 degrees C).     

Microwave radiometric measurements of sea surface temperature from the seasat satellite: first results

Initial results from the Seasat scanning multichannel microwave radiometer indicate that the sea surface temperature can be measured with a root-mean-square sensitivity of 1.2 degrees C or better. The first microwave map of sea surface temperature for the entire Pacific has been produced.     

基于根重的作物根系吸水模型初步研究

作物根系吸水受多种吲素影响,笔者在前人研究的基础上,从根系自身生物量变化的角度,依据土壤水动力学原理．构建以根重为因变量的根系吸水模型。采用均方根洪差（RMsE）和平均绝对百分误差（MAPE）2个评价指标对模型进行检验和评价。结果表明．RMSE全年统计的变化范嗣O．477～1．231．MAPE全年统计的变化范同1．082％～4,052％．平均RMSE为O．810,平均MAPE为2．520％．模拟精度基本满足要求。说叫建立的根系吸水数值模型及编写的程序具有较高的模拟精度,能够较好地模拟自然条件下作物生长期间的土壤水分动态变化,．     

遥感监测中5种相对辐射校正方法研究

相对辐射校正能够减小多时相遥感图像之间由大气、照度、物候和传感器标度等差异造成的影响,有利于提高动态监测精度.利用浙江省嘉善县两期TM/ETM+遥感数据,试验了5种相对辐射校正方法,包括图像回归法、伪不变特征法、暗集-亮集法、未变化集辐射归一法与直方图匹配法.这些相对辐射校正方法仅利用图像像元灰度值的统计特征,不需要其它参数,操作简便,尤其适合用于历史遥感数据本文运用均方根误差与变动范围这两个统计特征参数比较与评价了5种方法辐射校正后的图像,并用差值法进一步比较了5种方法对动态监测的影响,结果表明5种相对大气辐射校正方法都不同程度地改善了动态监测效果,对于本实验区,暗集-亮集法效果最好,其次为伪不变特征法.最后,本文还讨论了应用这5种方法的影响因素与适用条件.     

基于激光诱导击穿光谱的地下水中Fe和Mn的检测

采用激光诱导击穿光谱(LIBS)技术并结合在锌基板上液固转换的样品处理方法,对标准水溶液样品中Fe、Mn进行检测,并根据标准曲线法建立Fe、Mn的定量模型;再利用所建立的LIBS定量模型,对洞庭湖区地下水实际水样中Fe、Mn含量进行检测,并与电感耦合等离子体质谱法(ICP–MS)的检测结果进行比较。结果表明：得到Fe、Mn的LIBS定标曲线的决定系数均大于0.98,相对标准偏差均为4.3%,留一交叉验证均方根误差分别为0.024、0.007 mg/L,Fe、Mn的检出限分别为0.028、0.008 mg/L;采用LIBS对洞庭湖地下水实际水样中Fe、Mn含量检测的结果与ICP–MS的检测结果基本一致,平均相对误差小于10%。     

Development of the equine vibration arthrometry system (EVAS) for the study of equine lameness

Friction caused at different articular surfaces in horses’ joints can produce various vibration signals. In this study, we collected and analyzed the articular vibration signals in the fetlock joints of a healthy horse, an aged horse, and a horse with laminitis using the equine vibration arthrometry system (EVAS). The data obtained from the EVAS enabled the researchers to easily understand the condition of the horses’ inner joints and to differentiate between the joints of healthy limbs and those of diseased limbs with musculoskeletal disorders. Furthermore, we also developed mathematical algorithms to analyze the data from the EVAS in this study. We identified two periodic waveform cycles for each horse’s step in the time domain. The negative waveform cycle first appeared at each aged horse’s step. The root-mean-square (RMS) values of both the positive and negative waveform cycles were significantly larger at the first periodic waveform in the aged horse. In contrast, the positive waveform cycle first appeared in each healthy horse’s step and the RMS values of the positive waveform cycle were significantly larger in the healthy horse. We also measured the energy of the articular vibration signals of the healthy and aged horses in the first and second periodic waveform cycle during each horse’s step. By analyzing and comparing articular vibration signals in these horses, we were able to determine which of the horses had a musculoskeletal disorder. EVAS is a simple, convenient and non-invasive method of identifying articular problems in equine joints.     

Seasat visible and infrared radiometer

Visual and infrared images produced by the Seasat visible and infrared radiometer (VIRR) are adequate for the identification of cloud, land, and water features. A statistical comparison of VIRR-derived sea-surface temperatures in a cloud-free region with a National Oceanic and Atmospheric Administration analysis based on various surface measurements taken in the same region showed agreement to +/- 1.7 degrees K root-mean-square.     

Evaluating the grassland net primary productivity of southern China from 2000 to 2011 using a new climate productivity model

Grassland is the important component of the terrestrial ecosystems. Estimating net primary productivity(NPP) of grassland ecosystem has been a central focus in global climate change researches. To simulate the grassland NPP in southern China, we built a new climate productivity model, and validated the model with the measured data from different years in the past. The results showed that there was a logarithmic correlation between the grassland NPP and the mean annual temperature, and there was a linear positive correlation between the grassland NPP and the annual precipitation in southern China. All these results reached a very significant level(P0.01). There was a good correlation between the simulated and the measured NPP, with R2 of 0.8027, reaching the very significant level. Meanwhile, both root mean square errors(RMSE) and relative root-mean-square errors(RRMSE) stayed at a relatively low level, showing that the simulation results of the model were reliable. The NPP values in the study area had a decreasing trend from east to west and from south to north, and the mean NPP was 471.62 g C m~(-2) from 2000 to 2011. Additionally, there was a rising trend year by year for the mean annual NPP of southern grassland and the tilt rate of the mean annual NPP was 3.49 g C m~(-2) yr~(-1) in recent 12 years. The above results provided a new method for grassland NPP estimation in southern China.     

Harmonic oscillation as model for cortical excitability changes with attention in cats

A single shock to the prepyri-form cortex with implanted electrodes caused a damped, sinusoidal oscillation in potential. The root-mean-square amplitudes of potentials evoked by short trains of stimuli, when plotted against the frequency of stimulation, fitted the equation for forced harmonic oscillation when the cat was attentive to the stimuli     

洽川黄河湿地6种重金属污染分析研究(英文)

对黄河洽川湿地进行样品采集,采用国标法消化,测定了湿地土壤中Pb、Cd、Cr、Cu、Zn和Mn的含量,利用单因子污染指数、均方根综合污染指数和地积累污染指数法评价土壤重金属的污染程度。结果表明,洽川湿地采样范围重金属总体污染情况比较严重,污染主要来自重金属Cd,其他重金属造成的影响相对较小。