飞机重量误差计算及飞机重量值估算

一、前言在民用飞机的改型设计方案设计阶段时,需要进行全机及部件重量估算,这其中包括全机及部件的重量、重心位置和其自身惯性量和惯性积。根据广义矩阵理论,作者提出了本文所论述的方法。该方法可以根据一架或多架相类似飞机的真实重量数据,在改型飞机设计时候。

体力搬运重量限值标准的研制 Ⅰ.单次搬运重量的研究

选择体力劳动者为研究对象，研究不同年龄，性别，负重方式（搬，找,推／拉）和负重量对机体心率，劳累感等方面的影响，通过实验研究，提出我国体力搬运重量限值标准，单次负重量男性搬方式为15kg，扛方式为50kg，推或拉方式为300kg，女性搬方式为10kg，扛方式为20kg，推或拉方式为200kg。

浅谈水刺法非织造布重量CV值的控制方法

文章介绍了影响水刺非织造布重量CV值的重要因素、控制方法及控制前后的数据分析及结果。

AP1000燃料棒重量检测方法的建立

AP1000燃料棒重量检测是实现核燃料铀物料衡算的重要环节,其主要任务是对完成密封焊的燃料棒的重量进行测量,利用重量限值初步判断燃料棒组装的正确性,同时该检测方法测量结果的准确性直接影响核燃料的铀物料衡算是否准确。本文对燃料棒重量检测的方法和原理、重量限值的计算方法进行了介绍,并通过开展试验对该计算方法进行了验证,最终建立AP1000燃料棒重量检测方法。

称重传感器精确标定研究

一种发射药自动称量机为使发射药称重输出值能精确地反映称重值,对称重传感器精确标定进行研究。采用函数链神经网络法对称重系统称重检测值与实际重量值之间的函数关系进行精确标定,通过标定的称重系统精度≤1%,满足实际生产需要。

梳棉自调匀整装置在纺纱质量控制中的作用

探讨梳棉自调匀整装置在纺纱质量控制中的作用。阐述了生条不匀率波动的原因及特点,并通过长时间的跟踪监测,分析了梳棉自调匀整装置对生条重量内不匀和外不匀的影响,对比了三种自调匀整装置的匀整效果。数据表明:配置梳棉自调匀整装置可以将生条重量均匀度稳定控制在合理范围内;特吕茨勒一体式智能控制自调匀整系统的生条质量匀整效果较好。认为:保持清梳联系统的稳定运行,定期清洁保养自调匀整装置,可以更好地发挥梳棉自调匀整装置的匀整效果。

零相移带通滤波器在摆轮静平衡系统中的应用

本文针对手表摆轮静平衡系统中的偏重传感器输出信号在滤波过程中出现的相位偏移问题,设计了一种基于零相移算法的带通滤波器。首先,设计出适合于摆轮静平衡系统的巴特沃斯带通滤波器,再将零相移算法引入到带通滤波器中。仿真结果表明,所设计的基于零相移算法的带通滤波器,能够得到零相移的摆轮偏重量值信号。

Experimental Studies on Debris Flow with Logs Focusing on Specific Weight Difference of Log Species

There are many experimental approaches,field investigations and numerical calculations for movements of woods in a clear water and debris flow.However,kinematic conditions for accumulated logs and the interactions between a main flow and logs have not been fully evaluated.Mitigations for woods need taking into account the characteristics of tree species such as conifer and broad-leaf trees and of shapes such as root swells and crown.In the present study,we focus on the differences in specific weight of conifer and broad-leaf trees with some moisture in a sediment-water mixture flow with narrow flow width,and consider that conifer and broad-leaf tree are floating and submerged solid phase,respectively.Flume tests are conducted in steady flow of clear and debris flow over a rigid bed in order to evaluate conifer and broad-leaf tree movement in clear water and debris flow.Experimental data indicates that dimensionless transverse diffusion coefficient can be 0.1 to 0.4 and 0.3 to 0.9 in flow direction.Those diffusive characteristics seem to be independent of Reynolds number and Froude number,but dependent of bed slope,i.e.,gravity,though detailed considerations are needed to discuss about flow characteristics such as spatial eddy structures,momentum transfer induced by interactions of logs and so on.

PCA weight and Johnson transformation based alarm threshold optimization in chemical processes

To alleviate the heavy load of massive alarm on operators, alarm threshold in chemical processes was optimized with principal component analysis(PCA) weight and Johnson transformation in this paper. First, few variables that have high PCA weight factors are chosen as key variables. Given a total alarm frequency to these variables initially, the allowed alarm number for each variable is determined according to their sampling time and weight factors. Their alarm threshold and then control limit percentage are determined successively. The control limit percentage of non-key variables is determined with 3σ method alternatively. Second, raw data are transformed into normal distribution data with Johnson function for all variables before updating their alarm thresholds via inverse transformation of obtained control limit percentage. Alarm thresholds are optimized by iterating this process until the calculated alarm frequency reaches standard level(normally one alarm per minute). Finally,variables and their alarm thresholds are visualized in parallel coordinate to depict their variation trends concisely and clearly. Case studies on a simulated industrial atmospheric-vacuum crude distillation demonstrate that the proposed alarm threshold optimization strategy can effectively reduce false alarm rate in chemical processes.

Comprehensive Assessment of Seawater Quality Based on an Improved Attribute Recognition Model

The attribute recognition model (ARM) has been widely used to make comprehensive assessment in many engineering fields, such as environment, ecology, and economy. However, large numbers of experiments indicate that the value of weight vector has no relativity to its initial value but depends on the data of Quality Standard and actual samples. In the present study, the ARM is enhanced with the technique of data driving, which means some more groups of data from the Quality Standard are selected with the uniform random method to make the calculation of weight values more rational and more scientific. This improved attribute recognition model (IARM) is applied to a real case of assessment on seawater quality. The given example shows that the IARM has the merits of being simple in principle, easy to operate, and capable of producing objective results, and is therefore of use in evaluation problems in marine environment science.

Caloric Restriction and Litter Size Do Not Compromise Renal Function of Male Wistar Rats

This work had the purpose of comparing some renal parameters of Wistar rats raised in small litters either freely-fed （G3L） or subjected to 30% caloric restriction （G3R） with those of rats from normal litters （Gg） at the age of 90 days. The results showed that the relative weight of the kidneys and urinary flow were not significantly different. All the groups had GFR （glomerular filtration rate） and proteinuria within normal values, despite group G3R having values statistically lower. However, group G3R had diminished glomerular area and increased numbers of renal corpuscles. Group G3L did not exhibit differences compared with controls （G9）. The effects of caloric restriction did not compromise kidney structure and function in 90-day-old rats.

Influence of Dark Energy on Gravitational Time Delay

We investigate the gravitational time delay of light in the Schwarzschild black hole space-time surroundedby quintessence.With the analysis and numerical methods,we find that the gravitational time delay of light in theSchwarzschild black hole space-time surrounded by quintessence increases when the normalization factor c increases,andthat the gravitational time delay also decreases when the quintessential state parameter ω_q increases.

Numerical analysis on the shoot resistance of heat treated light weight B-grade bulletproof steel plates

Bulletproof steel plates are widely used for the safety of special vehicles.This paper mainly researches on the shoot resistance of heat treated light weight B-grade bulletproof steel plates through numerical analysis.Based on the flow behavior of bulletproof steel plates and bullet at various high strain rates,finite element(FE) model has been set up using ANSYS/LS-DYNA software.The simulation results are compared with the shooting results,which show a good consistency and a high reliability.Therefore,the simulation results are efficient approaches and strategies to decide and select the mechanical property and thickness of bulletproof steel plates,saving a lot of work and the cost of experiments.

Strong Consistency of Estimators of a Semiparametric Regression Model under Fixed Design

In this paper, we consider the following semipaxametric regression model under fixed design： yi = xi′β＋g（xi）＋ei. The estimators of β, g（·） and σ^2 axe obtained by using the least squares and usual nonparametric weight function method and their strong consistency is proved under the suitable conditions.

The Gravitational Force Quantum and its Value

Gravitation is one of the basic phenomena of the world. Tremendous number of theoretical works on origin, nature, essentials, consequences, etc. of the gravitation and related phenomena were published so far. The most prominent ones are based on the Albert Einstein＇s general theory of relativity. The author of this communication based his approach to the gravitation on Isaac Newton＇s law of the universal gravitation and related quantities, i.e. gravitational forces of matter objects, distance and motion. Namely on the fact, that the gravitation force is - as well as the inertia, mass, space ＂occupied＂ and other properties are - principal features/attributes/properties of matter objects. Gravitation is an additive property of matter objects. Taking into account other positivistic quantities like mass of the Earth, standard acceleration of gravity, and the value of the atomic unit of mass, the author defined a gravitational force of atomic unit （or ＂the Gravitational Force Quantum＂） as a gravitational force which exerts one atomic unit of Earth＇s mass on 1 kilogram of a mass on Earth＇s surface, and he calculated its value： GFO = 1.4958 × 10^-54 N. This quantity can be useful for further development of the ＂quantum mechanical＂ approach to the description and general notion about the world.

Molecular Weight Distributions of Cotton Cellulose Treated with a Polycarboxylic Acid at Different pH

In last paper, the average molecular weight of a control cotton fabric and cotton fabrics treated with the polycarboxylic acid at different pH were measured. The result doesnt support the hypothesis that the pH of the finishing bath can affect the depolymerization of the finished cotton fabric. In order to understand more about it, the molecular weight distributions of the control and finished cotton fabrics were measured and the reason was fund. From the ratio and the molecular weight of the low molecular part one can see that the pH of the finishing bath can affect the depolymerization of the finished cotton fabrics. The phenomenon that the average molecular weights of the cotton fabric crosslinked with BTCA at different pH are almost same is attributed to that the crosslinks are not broken completely when treated with 0.5 M NaOH solution at 50℃ for 144 h.

The Kinetic Study of Adsorption of Copper Metal Ion in Selected Contaminated Red Soil Samples in Palestine

Heavy metals are persistent pollutants in the environment. Problems associated with the cleanup of sites contaminated by metals have demonstrated the need to develop remediation technologies that are feasible, quick, and effective in a wide range of physical settings. In this study we have investigated the adsorption of Cu（lI）, onto red soil in single and multi-element systems as a function of soil and heavy metal concentrations. Before contamination, soils were characterized to determine particle size, pH, organic matter content and heavy metal contents. The results of experimental sorption data fitted very well the Freundlich isotherm model with n = 1.4 and k = 1.25 and first order kinetics model. The best pH for adsorption of Cu^2＋ on red soil was found to be 4.0. Adsorption of metals on soil increased in the order Cu 〉 Pb 〉 Zn ≈ Cd. This trend might be related to the increase in the electronegativity of the metal ion.

The Dual Effects of Global Value Chain Embeddedness on Chinese Exports’ Technological Sophistication

This paper develops a framework for the assessment of global value chain embeddedness based on the dual structure of product embeddedness and functional embeddedness and provides a theoretical demonstration of the dual effects of the level, structure and the value sources of global value chain embeddedness on export technology sophistication. From there, the paper carries out an estimation of non-competitive input- output table using quadratic optimized algorithm with differentiation between processing trade and general trade to arrive at various indicators of foreign value-added ratio that reflect the level of global value chain embeddedness. On this basis, the panel econometric model for 27 manufacturing sectors of China between 2001 and 2010 is employed to test the effect of foreign value-added ratio on the technology sophistication of manufacturing export. Our research indicates that by taking part in division of labor in the global value chain and acquiring foreign intermediate inputs, China＇s manufacturing sector has increased its export technology sophistication. It also indicates that, compared with such inputs as raw materials and parts and components, service input has great contributions to technology improvement. With the direct contributions of foreign value-added under control, the foreign value-added from developed countries has a restrictive effect on the R＆D activities of export manufacturing, which gives rise to the one-way technology reliance on dominant enterprises of the value chain and the ＂low-end lock-up＂ effect; meanwhile, the method of embeddedness that takes advantage of the foreign value-added of other countries is more dependent on the indigenous R＆D capacity of export enterprises and thus more favorable to the improvement of export technology sophistication.