The first-principles study on the doping effect of Re in Ni3A1

Using first-principles density function for molecules method (DMol) and discrete variational method (DVM) based on the density functional theory, we studied the doping effect of Re in Ni3Al. The structure relaxation and the alloying energy show that Re has a strong A1 site preference and leads to the local deformation, which is in agreement with the experimental results and other theoretical results. In addition, the charge density difference and the bond order show that Re can strongly enhance the interatomic interaction between the nearest neighbor atoms. From the density of states and the Pauli spectrum, we find that resonance states and localized states are induced by doping Re, and the doped Re atom forms the hybridized bond with the nearest neighbor atoms.     

融合零样本学习和小样本学习的弱监督学习方法综述

深度学习模型严重依赖于大量人工标注的数据，使得其在数据缺乏的特殊领域内应用严重受限。面对数据缺乏等现实挑战，很多学者针对数据依赖小的弱监督学习方法开展研究，出现了小样本学习、零样本学习等典型研究方向。对此，本文主要介绍了弱监督学习方法条件下的小样本学习和零样本学习，包括问题定义、当前主流方法以及实验设计方案，并对典型模型的分类性能进行对比。然后，给出零-小样本学习的问题描述，总结研究现状和实验设计，并对比典型方法的性能。最后，基于当前研究中出现的问题对未来研究方向进行展望，包括多种弱监督学习方法的融合与理论基础的探究，以及在其他领域的应用。     

连续测温法研究催化精馏过程宏观动力学

为甲缩醛合成流化催化精馏塔设计需要,建立了原颗粒催化剂宏观动力学快速测定法--连续测温法及其装置,测定了不同粒径催化剂上甲缩醛合成反应的宏观动力学数据,采用二级可逆反应球型等温催化剂有效因子的近似解析解,估计了有效扩散系数.     

Microtubular metazoan fossils with multi-branches in Weng’an Biota

Microtubular metazoan fossils with multibranches are found at least 4 times from the Sinian （Ediacarian） Doushantuo Formation at Weng＇an, Guizhou, China. Their living mode should be the benthonic colony with higher ability of asexual reproduction. The inner of the tube with cross-walls and chamber shows that these fossils are basal or stemgroup cnidarians, similar to extinct tabulates. The multi-branching microtubular fossils are real metazoan found from Weng＇an biota, which is very important for studying the origin and evolvement of metazoan.     

考虑多车型软时间窗的成品油二次配送库存-路径问题

针对成品油二次配送库存-路径问题(inventory routing problem, IRP),考虑了随机需求、多车型多隔舱等因素,以车辆配送成本、违反时间窗等惩罚成本之和最小化为目标,建立了混合整数规划模型。设计了求解模型的两阶段启发式算法,第一阶段根据各加油站的期初库存量、销量的概率分布等确定补货量和时间窗;第二阶段利用遗传算法和C-W节约算法确定配送车辆和配送路径。通过模拟计算并与单阶段算法和Gurobi直接求解模型的结果进行对比,验证了两阶段算法的有效性。结果显示利用本文方法确定成品油二次配送计划,在避免加油站缺货的同时,有效降低了车辆的配送成本。     

DWMT系统中滤波器组的新设计

研究了ＤＷＭＴ系统中的综合／分析滤波器组．基于系统对运算复杂度和子信道间频谱隔离特性的要求，我们采用了ＥＬＴ快速算法，并在滤波器优化设计过程中，用最大误差最小化准则替代了原ＥＬＴ算法中的最小均方误差准则     

Discovery of phosphatized gastrula fossils from the Doushantuo Formation, Weng’an, Guizhou Province, China

Globular fossils from Doushantuo phosphorites at the Weng’an area are for the first time identified as a gastrulation stage of phosphatized embryos. They are got from the fossiliferous remains after acetic acid maceration. The fossils are found together with formerly reported animal resting eggs and embryos of the earlier cleavage stage. The oblate-shaped fossils with the same size as those reported embryos and invaginate at the middle part into the embryos, show the characteristics of the late blastula to the early gastrula stage of the embryo development. This discovery convinces the existence of animal embryos at Doushantuo age and offers new facts for the studying of the affinity of related fossils, which are still controversial at present.     

First-principles investigation of the alloying effect of Ta and W on γ -TiAl

The alloying effect of the refractory elements Ta and W on the electronic structure of y-T\A\ is investigated by using the first-principles discrete variational method within the framework of density functional theory. The impurity formation energy result indicates that Ta and W can stay steadily in the TiAl system by way of substitution. The Mulliken population, density of states and charge density difference results show that Ta and W both give rise to the strong interaction between themselves and the neighboring host atoms. The alloying effect of the two elements onγ-TiAl is the same.     

MICROTUBULAR METAZOAN FOSSILS WITH MULTI-BRANCHES IN WENG’AN BIOTA

THE SINIAN DOUSHANTUO FORMATION AT WENG’AN, GUIZHOU PROVINCE, SOUTHWEST CHINA IS FAMOUS FOR THE WELL PRESERVED PHOSPHATIZED BIOTA. RECENTLY, THE FOSSILS OF ANIMAL RESTING EGGS AND EMBRYOS[1], SPONGES WITH CELLULAR STRUCTURE[2], GASTRULA[3], BILATERALITY …