水下湿法焊接等离子成分计算

水下湿法焊接所产生的电弧是在带电离子气体的气泡中形成的,结合前人对水下湿法焊接气泡成分的测定,分析了水下湿法焊接气泡中气体的主要解离和电离过程,对局部热力学平衡态下的不同水压、不同温度的水下电弧成分采用potapov模型进行了计算,其主要理论依据为Dalton分压定律、质量作用定律、电荷准中性条件和化学计量平衡条件.结果表明,随着水压由0.101 3 MPa变化到1.013 MPa再到10.13 MPa,离子体内H+,O,C,O+,C+的数密度呈现逐渐增加的趋势,同时电子数密度和离子体密度也跟随增加.而离子体总体平均电离度不受水压的影响.为进一步计算水下湿法焊接电弧的输运系数和水下电弧的仿真打下了基础.

首钢京唐公司4号双流板坯连铸机中间包混钢过程成分计算模型研究及应用

根据中间包流场理论以及首钢京唐公司4号双流板坯连铸机中间包的特点，研究开发出了首钢京唐公司4号双流板坯连铸机中间包混钢过程钢水成分计算模型。该模型能够模拟不同工艺条件下的混钢进程，计算流人结晶器的钢水化学成分，可以提供连浇时当前炉次钢包开浇的最佳中间包质量，使连浇过程中的混钢时间最短、问题坯长度最短；能够实时计算实际生产过程的混钢进程，从而实时掌握混钢过程新旧钢水的混合程度，对混钢时段板坯的质量判定和对此段板坯的优化切割具有一定指导意义。

成分计算法和差示量热法确定TA24合金相变点

采用成分计算法和差示扫描量热法测试了4种规格11件TA24近α钛合金试样的β转变温度。成分计算法根据合金元素及杂质对相变温度的贡献率来推算钛合金的β转变温度;差示扫描量热法根据钛合金发生相变时的热量变化测得β转变温度。结果表明:在置信度均取95%的条件下,方法间的偏差为(-1.3±5.8)℃,偏差绝对值为(2.4±3.9)℃。成分计算法和差示扫描量热法的测试结果相符,其偏差介于-6.9~2.4℃,均小于HB 6623.1—1992《钛合金β段变温度测定方法差热分析法》和HB 6623.2—1992《钛合金β转变温度测定方法金相法》规定的实验室内两次平行试验的允许差(±8℃)。成分计算法可以作为一种便捷有效的TA24钛合金β转变温度的快速预测方法。

主成分计算的改进自然幂迭代方法(英文)

提供快速估计与跟踪一个向量序列的主特征向量的改进自然幂迭代方法 .它是自然幂迭代方法的一个延伸 ,不仅跟踪主子空间 ,而且得到了主特征向量 .与一些基于幂迭代的方法 (例如Oja,PAST与NIC)相比 ,改进自然幂迭代方法具有最快的收敛速度 ,且能容易地以每步迭代O(np)的计算量加以实现 ,这里n为所考虑向量序列的维数 ,p为所要跟踪的主子空间的维数 (或主特征向量的个数 ) .与某些非幂迭代的方法 (例如MAL ASE与OPERA)相比 。

基于局部主成分保持投影的旋转机械故障数据降维方法

针对旋转机械高维故障特征集存在的特征冗余导致的分类困难问题,提出一种基于局部主成分保持投影(locality principal component preserving projection,LPCPP)的故障数据集降维算法。该算法将类间可分性判据、主成分计算两种思想与局部保持投影(locality preserving projection,LPP)相融合,使得算法具有剔除冗余特征、减小降维盲目性的能力,从而可以更好地保留能够反映机械运行状态的高价值密度的故障信息以及特征的主要成分。通过两个不同型号的双跨度转子系统的振动信号对所提算法进行验证,并分别以可分性指标和3种不同分类器的识别准确率对本算法的降维性能进行评价。结果表明,本算法能够达到降低故障分类难度与提高故障分类准确率的功能,其可为积累高价值密度的数据资源和基于“工业大数据”的旋转机械智能决策技术工程实现,提供一种数据运算的理论依据。

成人膳食中类胡萝卜素摄入量分析

目的了解成年人膳食类胡萝卜素的摄入状况。方法采用称重记录法,按季节调查城区、郊区、农村3类不同社区184名30-60岁居民连续3 d的膳食情况,参照1993年美国农业部-国家癌症研究院（USDA-NCI）食物类胡萝卜素数据库、1998年美国农业部-营养协调中心（USDA-NCC）食物类胡萝卜素成分数据库和最新版美国食物成分数据库（SR18）建立的α-胡萝卜素、β-胡萝卜素、β-隐黄质、番茄红素、叶黄素/玉米黄质5种类胡萝卜素的食物成分表,计算类胡萝卜素每日摄入量。结果α-胡萝卜素年平均摄入量为（274±539）μg,春、夏、秋、冬四季分别为（179±459）,（291±493）,（325±533）,（29l±650）μg。β-胡萝卜素的年平均摄入量为（3 207±3 921）μg,四季分别为（3 905±3 983）,（2 509±2 697）,（3 577±4 640）,（3 007±4 189）μg。β-隐黄质年平均摄入量为（140±582）μg,四季分别为（40±100）,（82±256）,（376±1 114）,（70±125）μg。番茄红素摄入量为（1 023±2 447）μg,四季分别为（971±1 539）,（2 184±3 565）,（324±1 543）,（390±1 622）μg。叶黄素/玉米黄质年平均摄入量为（2 937±4 512）μg,四季分别为（5 053±6 908）,（1 930±2 228）,（2 556±3 746）,（2 510±3 703）μg。α-胡萝卜素、β-隐黄质秋季摄入量最高,β-胡萝卜素、叶黄素/玉米黄质春季最高,番茄红素夏季最高。不同性别居民类胡萝卜素摄入量比较差异无统计学意义（P〉0.05）。城市居民的摄入量高于郊区和农村居民。结论利用美国类胡萝卜素成分数据,估计了成人膳食类胡萝卜素摄入量。

基于ARM的番茄叶绿素和氮的实时检测与3G传输

为了观测番茄本体成分的变化,实时监测番茄的生长状况,设计实现了基于ARM的番茄叶片叶绿素和氮含量实时监测与远程传输软件系统,集图像采集、处理和3G传输功能于一体。建立了番茄叶片图像中各颜色分量与叶片叶绿素及氮含量之间的回归方程,推导了番茄叶片叶绿素和氮含量的计算公式。研究结果为番茄生长状况的研究和生长环境的智能调控提供了依据。

测井资料提取中国大陆科学钻探PPII孔岩石物性

PPII ,即中国大陆科学钻探预先导孔—Ⅱ孔 ,该孔完钻深度为 1 0 2 8 6 8m ,钻孔直径 75 5mm ,中国大陆科学钻探在PPII孔进行了电阻率、自然电位、自然伽马、密度、中子、声波、成象等 1 0多种参数的测井 ,取得了宝贵的原位测井资料。本文利用测井资料、结合录井资料等划分岩性 ,对测井响应特征进行了分析 ,统计提取了该孔各种岩性的物性 ,利用交会图技术清晰地展示了该孔各种岩石的物性变化范围 (物性分区 ) ,同时 ,在提取岩石物性的基础上 ,利用BP人工网络识别了该孔的岩性 ,并根据榴辉岩、片麻岩的主要矿物组分 ,建立利用测井资料计算矿物成分的模型 ,并利用最优化方法测井求解响应方程组 。

基于PCA的“光纤液滴指纹图”识别液体研究

基于主成分分析(PCA)对提取“光纤液滴指纹图”的特征值进行研究。对40滴自来水样本进行主成分分析,由特征值大小及累积贡献率确定主成分的个数为6。计算40滴样本的主成分,得出第2,3,4主成分较稳定,第1,5,6主成分稳定性较差。对比40滴样本的“光纤液滴指纹图”的重合性,发现最后15%左右的数据曲线重合性较差,截掉此部分数据重新进行主成分分析,得出6个主成分的稳定性好,最大相对差异仅为8%。基于指纹图中前85%的数据,应用PCA算法对曲线形状较相似的10‰和20‰的盐水进行识别验证,得出二者的6个主成分差异性均显著,说明截掉不稳定的数据后对基于PCA算法识别液体的影响较小。

四川绵竹胶磷矿中铁铝杂质存在状态与活性研究

为得到绵竹胶磷矿中铁铝杂质的赋存状态,采用X射线衍射(XRD)、扫描电镜(SEM)、偏光显微镜对绵竹胶磷矿进行了矿相研究。针对铁铝杂质赋存状态的脉石矿物单体进行研究,总结出绵竹胶磷矿中铁铝杂质活性比例的评估手段。研究表明,绵竹磷矿中胶磷矿、碳酸盐矿物、硅酸盐矿物、铁质矿物、粘土矿物是其主要矿物单体。铁杂质主要赋存在以黄铁矿和褐铁矿为主的铁质矿物中,以黄铁矿形式存在的铁为萃取过程中的非活性铁。矿石中铝杂质主要赋存在以白水云母、蒙脱石为主的粘土矿物中,其中蒙脱石矿物中的铝比白水云母矿物中的铝萃出活性高。采用前处理方法——碱融和盐酸处理磷矿,可以得到准确的铁铝总量和活性质量分数,也可以通过物相成分计算方法估算铁铝活性质量分数。

慢性肾脏病病人3d饮食摄入量评估方法的探讨

[目的]通过对不同饮食评估方法的比较,旨在寻求一种方便使用且准确性良好的饮食摄入量评估方法。[方法]分别使用食物成分表计算法、中国肾病食物交换份法和改良肾病食物交换份法计算136例慢性肾脏病(CKD)病人饮食热量、蛋白质和优质蛋白比例的摄入情况,以食物成分表计算法为标准,比较中国肾病食物交换份法、改良肾病食物交换份法与食物成分表计算法的一致性及准确性。[结果]通过Bland-Altman分析,两种方法与食物成分表法计算的热量、蛋白量和优蛋比的差值均数落在95%一致性界限外的比例均不超过8.1%,但中国肾病食物交换份法计算的热量和蛋白质摄入量差值绝对值过大,分别为8.41kcal/kg和0.34g/kg,与食物成分表法一致性不佳;改良肾病食物交换份法与食物成分表法一致性较好,热量和蛋白质摄入量差值绝对值分别为4.12kcal/kg和0.26g/kg。比较两种计算方法与食物成分表法差异超过30%的比例,结果显示改良肾病食物交换份法计算热量和蛋白质摄入量的准确性好于中国肾病食物交换份法(P<0.05)。[结论]改良肾病食物交换份法可用于对CKD病人饮食热量和蛋白质摄入量的评估,在病人饮食评估中具备一定的应用价值。

Novel operating theatre scheduling method based on estimation of distribution algorithm

In order to improve the efficiency of operating rooms,reduce the costs for hospitals and improve the level of service qualities, a scheduling method was developed based on an estimation of distribution algorithm（ EDA）. First, a scheduling problem domain is described. Based on assignment constraints and resource capacity constraints, the mathematical programming models are set up with an objective function to minimize the system makespan. On the basis of the descriptions mentioned above, a solution policy of generating feasible scheduling solutions is established. Combined with the specific constraints of operating theatres, the EDA-based algorithm is put forward to solve scheduling problems. Finally, simulation experiments are designed to evaluate the scheduling method. The orthogonal table is chosen to determine the parameters in the proposed method. Then the genetic algorithm and the particle swarm optimization algorithm are chosen for comparison with the EDA-based algorithm, and the results indicate that the proposed method can decrease the makespan of the surgical system regardless of the size of operations. Moreover, the computation time of the EDA-based algorithm is only approximately 5 s when solving the large scale problems, which means that the proposed algorithm is suitable for carrying out an on-line scheduling optimization of the patients.

电厂混煤工程配方的修正

电厂混煤燃烧普遍存在,混煤方案中对基准的使用较混乱,需要考虑水份的变化进行各基准下成份的换算;同时,煤中有害成份的约束条件应以其实际影响的折算成份计算;混煤时,不但要考虑单煤的价格机械计算的混煤总价,更应综合考虑煤利用中总的性能价格比,这样才能更有效的充分利用能源。因此需要对现有混煤方案进行修正。

组织间信任:收益机制、情境限制及调节策略

在以往研究中,人们通常接受这样的假定:组织间信任必然会给组织与外部的交易带来正向收益。然而,组织间信任对交易收益也可能会产生组织不希望出现的负面影响。为此,我们重新审视了这一假说并发展了更为全面的理论框架来解释这一内部机制。首先,文章探讨组织间信任的内涵要素,进而分析组织间信任中计算性成分与非计算性成分的不同组合对交易收益的作用机制,从逻辑上推演出组织间信任与交易收益之间存在一种倒U型的关系;其次,提出两个重要的情境因素即信任的非对称性和环境的不确定性,讨论它们分别对上述倒U型关系的负向调节作用;再者,提出一组能够应对不同情境限制而同时仍然可增进或保持有益交易结果的调节策略;最后,讨论本研究的启示和未来研究可能的方向。

Simulation of gas-solid fluidized bed reactor for F-T synthesis

Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hypotheses. The consumption kinetic model of CO was investigated, and the parameters were estimated by UniversalGlobal Optimization with the Marquardt method. Residual error distribution and a statisticaltest show that the intrinsic kinetic models are reliable and acceptable. A model of carbonchain growth probability was established in terms of experiments. Coupled with the Ander-son- Schulz-Flory (ASF) distribution, the amount of specific product could be obtained.Large- scale cold model experiments were conducted to investigate the distribution of thegas (solid) phase and determine the function of the voidage with the location of the catalytic bed. The change tendencies of the components in the catalytic bed at different temperatures were computed and figured out. The calculated value computed by the modelestablished for the Fe-based F-T synthesis catalyst fit the experimental value very wellunder the same operating conditions, and all the absolute values of the relative deviationsare less than 5%.

A nonlinear PCA algorithm based on RBF neural networks

Traditional PCA is a linear method, but most engineering problems are nonlinear. Using the linear PCA in nonlinear problems may bring distorted and misleading results. Therefore, an approach of nonlinear principal component analysis (NLPCA) using radial basis function (RBF) neural network is developed in this paper. The orthogonal least squares (OLS) algorithm is used to train the RBF neural network. This method improves the training speed and prevents it from being trapped in local optimization. Results of two experiments show that this NLPCA method can effectively capture nonlinear correlation of nonlinear complex data, and improve the precision of the classification and the prediction.

ANALYSIS AND CALCULATION OF REGULATED WATER RESOURCES OF GROUNDWATER RESERVOIR

Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir. To resolve the problem of real-time quantification of regulated water, the paper analyzed sources and compositions of regulated water in detail. Then, under the conditions of satisfying water demand inside research area, the paper analyzed quantity available and regulation coefficient of different regulated water and established a formula to calculate regulated water. At last, based on a pore groundwater reservoir in the middle reaches of the Yinma River, Jilin Province, the paper calculated regulated water with the formula and the result shows that the method is feasible. With some constraint conditions, the formula can be adopted in other similar areas.

Wide-Band Multi-spectral Space for Color Representation

This paper develops a wide-band multi-spectral space for color representationwith Aitken PCA algorithm. This novel mathematical space using the broad-band spectra matchingmethod aims at improving the accuracy of color representation as well as reducing costs forprocessing and storing multi-spectral images. The results show that the space can present ourexperimental original spectral spaces (i. e. Munsell color matt and DIN-6164 color chips) with highefficiency, and that the spanning space with three eigenvectors can present the original space atmore than 98% CSCR, and when 5 eigenvectors are used it can cover almost the whole o-riginal spaces.

Explosion limits for combustible gases

Combustible gases in coal mines are composed of methane, hydrogen, some multi-carbon alkane gases and other gases. Based on a numerical calculation, the explosion limits of combustible gases were studied, showing that these limits are related to the concentrations of different components in the mixture. With an increase of C4H10 and C6H14, the Lower ExplosionLimit （LEL） and Upper Explosion-Limit （UEL） of a combustible gas mixture will decrease clearly. For every 0.1% increase in C4H10 and C6H14, the LEL decreases by about 0.19% and the UEL by about 0.3%. The results also prove that, by increasing the amount of H2, the UEL of a combustible gas mixture will increase considerably. If the level of HE increases by 0.1%, the UEL will increase by about 0.3%. However, H2 has only a small effect on the LEL of the combustible gas mixture. Our study provides a theoretical foundation for judging the explosion risk of an explosive gas mixture in mines.

Comprehensive Evaluation on Urban Sustainable Development of Harbin City in Northeast China

It is an effective way in realizing urban coordinated and sustainable development to establish a series of in- dicators and to evaluate urban environmental and socioeconomic development. According to the characteristics of Harbin City in Northeast China, an indicator system including five subsystems and 37 indicators was established for comprehensive evaluation on urban sustainable development. The development indexes of all urban subsystems and complex system were calculated quantitatively using the comprehensively integrated methods composed of Principle Component Analysis, Analytic Hierarchy Process and weighed index method, and then the comprehensive level of ur- ban sustainable development and the degree of urban interior coordination were analyzed. The results indicated that 1) the overall urban development presented an uptrend, however, the interior development was not well balanced from 1996 to 2006; 2) the development in each subsystem presented a strong fluctuation; and 3) the development in re- sources subsystem showed a downtrend. Based on those results, the suggestions of urban sustainable development were put forward at the end.