基于密集神经网络的灰度图像着色算法

针对在灰度图像着色领域中，传统算法信息提取率不高、着色效果不理想的问题，提出了基于密集神经网络的灰度图像着色算法，以实现改善着色效果，让人眼更好地观察图片信息的目的。利用密集神经网络的信息提取高效性，构建并训练了一个端到端的深度学习模型，对图像中的各类信息及特征进行提取。训练网络时与原图像进行对比，以逐渐减小网络输出结果的信息、分类等各类型的损失。训练完成后，只需向网络输入一张灰度图片，即可生成一张颜色饱满、鲜明逼真的彩色图片。实验结果表明，引入密集网络后，可有效改善着色过程中的漏色、细节信息损失、对比度低等问题，所提算法着色效果较基于VGG网络及U-Net、双流网络结构、残差网络（ResNet）等性能优异的先进着色算法而言取得了显著的改进。     

Refractive index of soft contact lens materials measured in packaging solution and standard phosphate buffered saline and the effect on back vertex power calculation

PurposeTo measure the refractive index (RI) of commonly available soft contact lens (CL) materials, their packaging solutions and compare to the manufacturers’ nominal RI. The relationship between RI versus water content, and the effect of inaccurate RI when converting lens power measured in solution to in-air back vertex power were examined.MethodsThe RI of 18 single vision soft CL materials were measured using CLR 12–70 digital refractometer. Three lenses of each material were measured, in their packaging solution and then after soaking in standard phosphate buffered saline (PBS). The RIs of packaging solution were also measured. Accuracy requirements for correct wet to dry power conversion based on thick lens formula were projected.ResultsThe standard deviation between three samples was less than 0.005. The measured RI ranged from 1.3744 ± 0.001–1.4265 ± 0.0004 for PBS soaked and from 1.3739 ± 0.0003–1.4264 ± 0.0024 for packaging solution soaked materials. Comparing nominal with mean measured PBS and packaging solution RIs, 5 and 3 lens materials, respectively, fell outside ISO tolerance. The packaging solution RI of DailiesAquaComfortPlus had the largest difference of 0.0040, compared to RI of standard PBS. For converting lens power measured in PBS to in-air power, the difference between measured and nominal RI of 0.0104 would result in wrongly calculated in-air power 0.99 D for a -6.00 D lens.ConclusionThe CLR 12–70 is reliable and accurate refractometer for the measurement of soft CL materials. Accurate RI measurements are of relevance with increased use of wavefront sensors to measure lens power while they are immersed in solution. Even small errors in solution or material RI can lead to significant errors in converted in-air power. To obtain valid in-air lens power results, measurement conditions must match the material and solution RIs used for the conversion.     

γ射线辐照和阳光照射对ZF6铅玻璃透光率的影响

通过实验研究ZF6铅玻璃在~(60)Co放射源相同剂量率不同累积剂量照射下透光率的变化规律。将辐照后的铅玻璃在室外阳光下、室内自然光下和不透光的抽屉中放置观察,发现阳光照射对铅玻璃辐照着色的恢复起着重要作用,在建立铅玻璃透光率随辐照时间变化的数学模型时,室内自然光对铅玻璃透光率的影响可忽略。实验数据验证了受辐照时铅玻璃透光率的变化与辐照时间符合指数函数关系。根据文献资料推导出铅玻璃透光率变化与光照时间为线性函数关系,但发现其与实验数据的符合程度较差,本文根据样条曲线插值法推导出铅玻璃透光率与光照时间为二次函数关系,与实验数据的符合效果较好。     

A fuzzy irregular cellular automata-based method for the vertex colouring problem

ABSTRACT

Vertex colouring is among the most important problems in graph theory which has been widely applied across different real-world problems. In vertex colouring problem (VCP), the goal is to assign a distinct colour to each vertex of the graph in such a way that no two adjacent vertices have the same colour. This paper presents a fuzzy irregular cellular automaton (FICA) for finding a near-optimal solution for the VCP. FICA is an extension fuzzy cellular automaton (FCA) in which the cells of the automaton can be arranged in an irregular structure. The aim of the proposed method is to reap the benefits of both FCA and irregular cellular automata while minimising their drawbacks. To evaluate the proposed method, various computer simulations have been conducted on a variety of graphs. The results suggest that the proposed method is able to achieve better results in terms of the minimum number of required colours and the execution time of the algorithm, compared to other peer algorithms.     

Modified cuckoo optimization algorithm (MCOA) to solve graph coloring problem

In recent years, various heuristic optimization methods have been developed. Many of these methods are inspired by swarm behaviors in nature, such as particle swarm optimization (PSO), firefly algorithm (FA) and cuckoo optimization algorithm (COA). Recently introduced COA, has proven its excellent capabilities, such as faster convergence and better global minimum achievement. In this paper a new approach for solving graph coloring problem based on COA was presented. Since COA at first was presented for solving continuous optimization problems, in this paper we use the COA for the graph coloring problem, we need a discrete COA. Hence, to apply COA to discrete search space, the standard arithmetic operators such as addition, subtraction and multiplication existent in COA migration operator based on the distance's theory needs to be redefined in the discrete space. Redefinition of the concept of the difference between the two habitats as the list of differential movements, COA is equipped with a means of solving the discrete nature of the non-permutation. A set of graph coloring benchmark problems are solved and its performance is compared with some well-known heuristic search methods. The obtained results confirm the high performance of the proposed method.     

混合实验法在W-Ni-Cu合金组分设计中的应用

采用极端顶点设计法设计W-Ni-Cu合金组分,将组分自变量与相对应的性能因变量(相对密度、显微硬度、抗弯强度)进行回归分析和规划求解,同时采用冷压烧结法制备不同组分的W-Ni-Cu合金,测定合金的密度、显微硬度和力学性能,研究组分对合金性能的影响。结果表明:回归方程复相关系数R~2=1,方程精确度高;合金性能随组分变化而呈规律变化;当Ni含量与Cu含量(均为质量分数)分别为3%和5%时,合金的综合力学性能最佳:相对密度为94.295%、显微硬度286.55、抗弯强度931.51 MPa。W-Ni-Cu合金的相对密度计算值与实验结果的误差为-0.45%~0.06%,显微硬度计算值与实验结果的误差为-8.48%~4.46%,抗弯强度计算值与实验结果的误差为-5.19%~4.15%。误差很小,说明混合实验和极端顶点设计法能优化W-Ni-Cu合金组分,并可靠预测合金性能。     

Deep‐black‐coloring effect of fabrics made of noncircular cross‐section polyester filaments

The effects of noncircular cross‐section (NCCS) poly ethylene terephthalate (PET) filaments and its shape factor on deep‐black‐coloring of dyed fabrics were investigated by comparing to that of the circular cross‐section PET ones. Indexes such as K/S, L* and Integ values were used for characterizing the deep‐black‐coloring effect on fabrics. The results indicated that fabrics made with NCCS PET filaments exhibited good deep‐black‐coloring effects. The calculated shape factor of the NCCS PET fiber had a significant correlation with the degree of deep‐black‐coloring exhibited by the fabric made from the fibers. A qualitative optical analysis of the NCCS PET fibers was carried out to explain the causes of the deep‐coloring of the NCCS fibers. This analysis implies that the contours of the NCCS fiber composed of surfaces with varied curvature increase the scattering of light by lowering specular reflection and increasing interior reflected and refracted light. This, in turn, strengthens the deep‐coloring effect. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 511–518, 2014     

A note on total colorings of 1-planar graphs

A 1-planar graph is a graph that can be drawn in the plane such that each edge is crossed by at most one other edge. In this paper we give an upper bound for the total chromatic number for 1-planar graphs with maximum degree at least 10.     

水基液体磁性磨具复合分散剂配方实验研究

为提高水性液体磁性磨具的稳定性,制备以六偏磷酸钠与聚丙烯酸(PAA)为表面活性剂、纳米二氧化硅为辅助剂的复合分散剂。通过Minitab软件的DOE实验设计模块,以水基液体磁性磨具的沉淀率和零场黏度为评价指标,采用极端形顶点设计复合分散剂的配方并实验研究复合分散剂各组分对沉淀率和零场黏度的影响。结果表明:六偏磷酸钠与PAA之间存在协同作用,纳米二氧化硅对水基液体磁性磨具的零场黏度起到重要作用,三者能够很好地提高水基液体磁性磨具的稳定性。综合考虑沉降率和零场黏度,确定复合分散剂的最佳配比,并通过实验验证了预测值的准确性。     

基于顶点索引的三维建模与可视化方法研究

分析了影响三维建模与可视化效率的主要因素,设计了一种新的基于顶点索引的三维模型数据组织方式,相对于传统的3DS模型文件,该方法避免了大量冗余数据的处理,并能充分发挥图形显卡高效的数据传输特性,经验证:显著提高了模型绘制的效率,较好地解决了复杂模型高效三维可视化的问题。