A Performance Evaluation of Classic Convolutional Neural Networks for 2D and 3D Palmprint and Palm Vein Recognition

Palmprint recognition and palm vein recognition are two emerging biometrics technologies. In the past two decades, many traditional methods have been proposed for palmprint recognition and palm vein recognition, and have achieved impressive results. However, the research on deep learning-based palmprint recognition and palm vein recognition is still very preliminary. In this paper, in order to investigate the problem of deep learning based 2D and 3D palmprint recognition and palm vein recognition in-depth, we conduct performance evaluation of seventeen representative and classic convolutional neural networks (CNNs) on one 3D palmprint database, five 2D palmprint databases and two palm vein databases. A lot of experiments have been carried out in the conditions of different network structures, different learning rates, and different numbers of network layers. We have also conducted experiments on both separate data mode and mixed data mode. Experimental results show that these classic CNNs can achieve promising recognition results, and the recognition performance of recently proposed CNNs is better. Particularly, among classic CNNs, one of the recently proposed classic CNNs, i.e., EfficientNet achieves the best recognition accuracy. However, the recognition performance of classic CNNs is still slightly worse than that of some traditional recognition methods.

     

Protein interaction networks: centrality,modularity, dynamics,and applications

In the post-genomic era, proteomics has achieved significant theoretical and practical advances with the development of high-throughput technologies. Especially the rapid accumulation of protein-protein interactions (PPIs) provides a foundation for constructing protein interaction networks (PINs), which can furnish a new perspective for understanding cellular organizations, processes, and functions at network level. In this paper, we present a comprehensive survey on three main characteristics of PINs: centrality, modularity, and dynamics. 1) Different centrality measures, which are used to calculate the importance of proteins, are summarized based on the structural characteristics of PINs or on the basis of its integrated biological information; 2) Different modularity definitions and various clustering algorithms for predicting protein complexes or identifying functional modules are introduced; 3) The dynamics of proteins, PPIs and sub-networks are discussed, respectively. Finally, the main applications of PINs in the complex diseases are reviewed, and the challenges and future research directions are also discussed.     

高分2号图像业务化大气校正查找表的设计与实现

为实现高分2号图像(GF2)业务化大气校正,利用矢量6S模型(6SV)将辐射传输散射与吸收进行分离计算,其中散射部分采用涵盖各种大气模式、气溶胶类型、成像几何等条件下的大气校正查找表(look-up tables,LUTs)表示,大气吸收部分采用6SV拟合计算的6种大气模式下大气透过率的经验公式表示,这种处理有效简化了查找表大小.在内存4 GB、主频3.10 GHz条件下,通过比较基于本查找表方法和基于FLAASH大气校正软件对北京地区一景GF2数据处理.结果表明:以6SV模型直接大气校正法结果作为真值,两者的绝对误差分别为0.8%和2.6%,处理时间分别为77 s和240 s,该大气校正查找表在处理精度和效率更加适合业务化大气校正.     

层间接触状态和横向力大小对车辙贡献率的影响

车辙贡献率是反映沥青路面各结构层车辙病害程度的一个主要参数,可用于指导沥青路面的设计和施工.利用三维有限元计算软件建立三维有限元模型用于理论分析,将有限元计算结果与理论解进行对比,验证了该三维有限元模型的可靠性.采用实测的轮胎接地压力,考虑不同层间接触状态和横向力大小,结合有限元计算的数据,分析了沥青路面结构层的车辙贡献率.结果表明:在层间完全连续状态下,横向力大小的选取不能简单地选取最大垂直轮胎接地压力的一定比例,而是要根据所研究的具体情况具体分析.在对沥青路面车辙贡献率的研究中,可以忽略层间接触状态,即假定层间完全连续.     

破乳剂与原油管道混合流动的数值模拟

原油开采过程中,原油遇水能够形成比较稳定的乳化液,添加破乳剂是快速高效脱去原油中水的最有效的方法。对破乳剂与原油两相混合的流动形态进行了数值模拟,得出破乳剂在不同速度、不同入口角度下加入原油管道后两相流动的速度分布图和浓度分布图。经过对比发现,当药剂入口角度为0°,药剂流入速度越大,越有利于破乳剂的扩散,破乳剂和原油的混合效果最好,就更有利于原油的脱水。     

Ni-Cr-Fe-Si-B合金涂层及铝青铜基体熔合区组织的研究

采用钨极氩弧焊方法在铝青铜基体上施焊了Ni—Cr-Fe-Si—B合金涂层，并运用金相显微镜、扫描电子显微镜及能谱分析了喷涂层、熔合区及热影响区的组织形貌和成分分布。结果表明，喷焊时，在涂层与基体界面两侧各组元均发生了明显的扩散，Cu、Ni组元间可相互取代，基体融合区组织的基本组成仍为α (α γ2)，但同时也形成了Cu2FeAl7、NiAl3等新相，且融合区组织细小，涂层与基体间为冶金态结合。     

保温条件下过共晶Al-Si合金半固态浆料的组织演变

研究了保温时间和保温温度对电磁搅拌ZL117合金半固态浆料稳定性的影响.试验结果表明：半固态浆料中初生Si的颗粒直径随着保温时间的延长而逐渐增大,但在前15 min内增长速度比较缓慢,15 min后增长较快;随着保温温度的升高而缓慢增大;初生Si的形状系数随着保温时间的延长而变得越来越大,但也在前15 min内变化较为缓慢,15 min后变大速度突然加快;初生Si的形状系数在620 ℃下保温时最小,在610～620 ℃之间随着保温温度的升高而缓慢变小;在620～650 ℃之间随着保温温度的升高而逐渐增加.     

烷基磺酸钠型砂的质量控制

介绍了控制烷基磺酸钠型砂的混砂工艺、配制要点及保存使用等控制要点，并就实际生产中可能出现的一些问题作了探讨，提出了解决的办法。     

活性炭吸附硫脲溶液中的金离子之形态

由实验得出活性炭从硫脲溶液中吸附金的特点,根据络合化学原理找到溶液中被吸附离子形态是AuTu~+,AuTu_2~+和Au~+,并解释了实验现象。     

Thermodynamic reassessment of the Cd−Zn system

The Cd−Zn system has been thermodynamically reassessed with the CALPHAD method by combining more recent experimental data, in particular the activities of zinc in the liquid phase. A good agreement is obtained between the calculated and experimental thermodynamic parameters as well asphase boundaries.