基于OSA-UCS数据的CIECAM02图像复制色差评价

目的为了改进彩色图像复制时在不同观测环境下的误差,将优化后的色貌模型引入色彩信息转换。方法在分析CIECAM02-Jab用于彩色图像复制的色彩评价的基础上,提出利用OSA-UCS数据集建立新的优化色貌空间实验方案。利用线性回归的方法,调整原始颜色空间中的明度和彩度,构建出新的均匀颜色空间J_xa_xb_x。结果经过检验发现新的优化色貌空间J_xa_xb_x色差的离散程度减轻,空间更趋均匀,更加符合均匀性标准。结论新的优化色貌空间J_xa_xb_x修正了均匀颜色空间的均匀性,比CAM02初始色貌空间有了一定程度的提高,对彩色图像复制的色差评价取得了一定的效果。     

封头结构对板翅式换热器流体分配性能的影响

研究了板翅式换热器封头高度与流体分配之间的关系,实验结果说明板翅式换热器的流体分配与封头高度有很大关系,封头高度越高流体分配就越均匀.引入不均匀参数,以便可以对流体在出口截面的分配特性进行研究,并进一步研究封头结构型式不同对于流体分配的影响,研究表明:换热器内部流体的流速的最大值与最小值的比值由3-4减少到1.1-1.2,其不均匀度也从原来的0.331减少到0.046.     

利用离散平稳小波变换改进NURBS二次曲面拟合方法

为了提高二次曲面的拟合精度,提出了一种基于离散平稳小波变换的NURBS二次曲面的拟合方法。 首先利用格网化方法得到二次曲面模型点云数据的高程图像及其高程序列,其次对此高程序列进行离散平稳小波变换提取出二次曲面模型表面的特征点,最后利用提取的特征点实现高精度NURBS二次曲面拟合。实验结果表明,该方法与NURBS拟合方法相比,球面和圆锥面拟合结果的均方根误差分别降低了55.79%和50.47%,具有较高的拟合精度。     

离散频谱分析中两邻近谱峰参数的识别

在理论概括比值法原理的基础上,提出一种新的自动识别和修正离散频谱中两邻近谱峰参数的方法.它保留了比值法计算简单的特点FFT谱分析时无需增加样本长度,谱峰参数修正识别的算法简单,无迭代搜索过程.不仅能识别间距不到一个频率分辨率的两个密集频率成份,而且能识别峰间距为1～6个频率分辨率的邻近谱峰参数,从而与比值法相辅相成,形成了一套完整的离散频率信号分析方法.仿真研究表明,该方法能有效克服窗谱函数主瓣干涉和旁瓣泄漏的影响,识别精度较高当峰间距大于0.2倍频率分辨率时,对于两个频率分量的各种截断情况,均能保证幅度误差小于6%,相位误差在5°以内.     

包装颜色空间不均匀性的数理研究

颜色空间的不均匀性是造成包装设计原稿与包装产品之间色差的重要原因。本文从数理角度研究了颜色空间不均匀性产生的原因,介绍了一种新的颜色空间模型——仿射颜色空间,并探讨了颜色空间在包装设计中的选择和应用。     

HHHT抽水蓄能电站地下主厂房母线层通风模型试验研究

通过HHHT抽水蓄能电站地下主厂房1：20缩尺模型来研究其母线层气流组织分布。在56m^3/h及112m^3／h的两种风量下,分别选择5种送风口方案1～5,对母线层工作区温度场及速度场进行测试。未封闭吊物孔、未安装接力风机时的温度分布标准差最大值为0．95,最小值为0．42：封闭吊物孔、安装接力风机后的温度分布标准差最大值为0．35,最小值为0．08。研究表明,封闭吊物孔、安装接力风机加强了母线层工作区气流组织分布的均匀性,双排对称布置送风口（方案5）为最佳送风口方案。研究结果为HHHT及相关电站地下厂房复杂气流的优化组织设计提供了参考依据。     

影院建筑声学标准与测量(下)

2.声场分布及声缺陷的测量: 在影院及其它厅堂中,为使观(听)众区内任意位置都能清楚地听到对白、语言、音乐、动效等内容,故声场分布的均匀性也极为重要。 在相关标准中规定“在观众区内各测试点间声压级的最大值与最小值之差不大于6dB,最大值与平均值之差不大于3dB。”     

供料方式对垂直螺旋输送机性能的影响

为了研究供料口处物料呈现的不均匀现象,分别建立了重力型和水平型2种供料方式下的垂直螺旋输送机计算模型,采用离散元法,借助EDEM软件,通过试验和标定的方式对模拟参数,如进口速度、时间步长和颗粒属性参数进行确定,进而确保模型和参数选取的可行性;分别对2种供料方式进行模拟,以颗粒数标准偏差为评价指标。结果表明:与重力型供料相比,在相同的操作条件下,水平型供料方式在供料口取样区域的物料不均匀度更高,物料输送的均匀性更低,螺旋转速的改变对2种供料方式下取样区域颗粒质量分布的均匀性影响较大,针对重力型和水平型供料方式给出了结构改进建议。     

封头形状对板翅式换热器入口段流场影响的数值研究

板翅式换热器入口段存在流场分布不均匀,并由此会引起换热效率低下.首先从封头曲线对流体的引导作用出发,进而优化换热器入口段流场均匀性,提出了板翅式换热器一次封头进一步的改进和优化思路和方法.即结合封头截面曲线函数及其导数特性,将前人提出的下抛物型一次封头改进为上抛物型和正切型,并利用CFD数值模拟方法对3种封头条件下换热器入口段的流场分布进行了对比研究.研究结果表明,使用后两种曲线的封头时,换热器入口段的物流分配更为均匀,在入口条件为7 m/s时,流速不均匀度由封头Ⅰ的5.9分别下降到0.5和0.4;流速最大值与最小值之比由封头Ⅰ的73.6分别下降到60.5和41.5.     

数控加工仿真中的优化离散矢量模型

数控加工仿真是利用计算机模拟数控加工的过程。采用离散知音一法可以有较好的实时性和观察性。但在采用离散矢量法时，离散模型的建立对仿真的效果有很大的影响。而对于常用的彩和均匀离散方式建立起来的仿真模型，对仿真精度与仿真速度的要求无法同时得到满足，本文采用了一种基于非均匀离散的优化模型可以有效地解决此点不足，并将详细论述这种仿真模型的建立、数据更新及其显示等内容。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Effect of Permeable Crystalline Material on Steel Reinforcement Corrosion of Concrete

Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.     

The Research and Application About "Dry Peeling Off" Technology for Airplane Surface Paint Layer

In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.     

Quality Study of Honeycomb Core Shaping Without Wax Stabilization

Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

In-process thermal treatment of polylactic acid in fused deposition modelling

Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.