摘要：Tin monosulfide(Sn S), which is composed of earth-abundant elements, holds promise as useful high-performance solar absorber and thermoelectric material. In addition to the ground-state Pnma phase, a series of metastable phases in different crystalline structures have been reported experimentally or theoretically, yet the phase stability diagrams remain elusive. In this article, we provide a comprehensive materials design study of new phases of Sn S using first-principles global optimization structure search calculations. We find that the two-dimensional layered phases are generally more energetically favored than the three-dimensional connected phases. In addition, we discover several new phases with comparable energetics. Four lower-energy phases show clear phonon stabilities evidenced by an absence of imaginary modes. The electronic band structures, carrier transport properties, and absorption spectra of the newly discovered phases are investigated and discussed toward potential applications for solar cells and thermoelectric devices.

摘要：对框架式导引头视线稳定回路控制问题,提出了自抗扰控制器设计方法。视线稳定回路双通道所受干扰具有不确定性,通过线性扩张状态观测器对系统的总和扰动实时估计并予以动态补偿,使被控对象化为"积分器串联型",再利用跟踪微分器和PD控制设计ADRC控制律。试验结果表明,在低成本约束条件下,ADRC能将隔离度从7.5%降低到3%,较PID控制有更好的控制品质。

摘要：深水多功能水下工程作业船是一艘配置大型水下工程作业装备、集成多项水下作业功能的深水海域油气田开采配套船舶。该船集大型深水水下结构物安装、柔性管/电缆铺设、水下机器人(ROV)、锚系处理和潜水支持等多项功能于一身。该船安装以及预设作业功能布置的大型作业设备,体积庞大、额定负荷高,船体结构要承受巨大的作业载荷。同时根据深水工程作业的要求,设备的配置和船体结构布局需要综合协调优化,以满足船体结构的强度要求和深水水下工程作业的功能实现。

摘要：针对多物品库存系统中常见的联合补货-配送问题,挖掘了其数学模型中的一系列性质,并提出了一种ε-最优算法和一个对偶下界.实验结果表明,本文设计的算法效果超过了现有研究中表现最好的几种元启发式算法,对目标值的提升幅度最高能达到31%,对偶下界与最优值的偏差较小,平均不超过0.84%.新算法运算效率较高,100个商品的算例平均运算时间不超过23秒.此外,本文还对算法时间复杂度进行了分析,在实际应用环境中,该算法能够达到O(n)级多项式时间复杂度,这一结论可为联合补货-配送问题的算法设计理论提供有益的补充.最后,对协同配送策略的效益进行了分析.实验发现,只有当中心仓库的库存管理水平相比零售商处的库存管理水平有较大优势时,协同配送才能够取得较高的成本节约效益.

摘要：目前,储能技术是目前解决可再生能源发电难并网的关键技术,而压缩空气储能(CAES)是大规模物理储能最合适的选择之一。压缩空气储能系统在非设计工况下运行会对系统的运行效率产生不利的影响,尤其将绝热压缩和等温压缩相结合,并使用TES储存压缩热的CAES系统的非设计工况比较复杂。因此本文考虑了该系统全设备的变工况模型,揭示了压缩机部分负荷时系统的详细动态性能,并研究了几种操作策略分别在储能阶段和释能阶段对系统变工况性能的影响。结果表明,在储能阶段的操作策略中,系统在部分负荷运行时,系统效率和TES的释热率都随负荷的增大而增大,但在特定情况下,系统效率有下降的趋势。

摘要：为了跟踪国内外海上水面自主船舶(MASS)发展进程,深化对MASS自主性的理解,对国内外MASS在标准规范及科研项目上的发展进行梳理;通过绘制时间尺度上的人机运行机制图对MASS自主性进行解析并以航行感知系统为例进行实例化解读;对MASS的风险评估、模型基础、试验实践内容进行展望。总结分析目前MASS现状和主要问题,提出MASS的3种自主运行模式,为MASS的详细设计及未来发展提供依据和思路。

摘要：针对建筑施工现场涉及的越障、攀爬等复杂非结构化场景,为提升机器人的整机性能,提出了一种基于轮履切换的建筑移动机器人。首先,在传统单履带基础上设计了子母履带辅助攀爬机构,基于激光雷达、惯性测量单元等多传感融合的空间定位与建图,利用基于运动学约束的信息树扩展算法对随机环境中的机器人进行了路径规划;然后,建立了含重心偏移、滑移等非线性扰动的运动学和动力学方程,综合考虑了实际作业过程中的强耦合、非线性、建模误差等不确定性因素,设计了一种基于自适应模糊分数阶的PID控制方法;最后,根据仿真分析与实验,验证了机器人的整机灵活性、高可靠性及多场景适应能力。研究结果表明:基于轮履切换的机械结构对复杂场景具有良好的适应能力;路径规划平均缩短路径长度9.08%,缩减行程时间39.83%;控制系统可在保障运动稳定性、动作协调性的同时减小位置误差,实现对机器人的精确控制目的,满足复杂施工环境下机器人的作业需求。

摘要：To satisfy the mechanical and biological requirement of porous bone substitutes, porous Ti with two different pore sizes designed in advance was fabricated by the space-holder sintering process. Mechanical properties of the porous Ti were explored via room temperature compressive tests. The pore sizes and shapes are uniform throughout the specimens with porosities ranging from 36% to 63%. The compression strength and the elastic modulus are in the range from 94.05 to 468.57 MPa and 2.662 to 18 GPa, respectively. It is worth noting that the relationship between the compressive strength and the porosities is completely linear relation beyond the effect of pore size distributions on the mechanical properties. The value of the constant C achieved from the Gibson-Ashby model suggests that the pore sizes affect the yield strength of the porous Ti and the values of density exponent （n） for porous Ti with two different pore sizes are higher than 2, which suggests that the deformation mode of the porous Ti with a porosity ranging from 36% to 63% is mainly buckling of the cell struts.

摘要：The orbitofrontal cortex(OFC)is involved in diverse brain functions via its extensive projections to multiple target *** is a growing understanding of the overall outputs of the OFC at the population level,but reports of the projection patterns of individual OFC neurons across different cortical layers remain ***,by combining neuronal sparse and bright labeling with a whole-brain florescence imaging system(fMOST),we obtained an uninterrupted three-dimensional whole-brain dataset and achieved the full morphological reconstruction of 25 OFC pyramidal *** compared the wholebrain projection targets of these individual OFC neurons in different cortical layers as well as in the same cortical *** found cortical layer-dependent projections characterized by divergent patterns for information *** study not only provides a structural basis for understanding the principles of laminar organizations in the OFC,but also provides clues for future functional and behavioral studies on OFC pyramidal neurons.

摘要：A mobile mechanism with four tracked-units for a missing miner search robot (MMSR) is presented, with a design based on the terrain features and atrocious environment of an underground mine. Its structure and working prin- ciple is discussed. The four tracked-units are controlled independently and driven cooperatively. By means of two DC motors being controlled respectively, one tracked-unit can accomplish two types of driving mode: tracked travel and in- tegral unit legged rotation (IULR), forming a track-legged compound function mechanism. Its capabilities of surmount- ing obstacles and its toppling stability in underground mines have also been analyzed. The results show that the mobile mechanism can directly surmount an obstacle of the height less than the length of one tracked-unit and get across a raceway with a span less than the length of one tracked-unit by using tracked travel and IULR. Its unstable slope angle is 51.3°. Toppling stability is determined by its structural size, moving direction and slope angle. IULR of four tracked-units can adjust the robot’s posture and then enhance toppling stability or assist in surmounting obstacles. Its track-legged compound function mechanism makes it suitable for working in underground mines.