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关键词： 城市综合体   非结构构件   交通流线功能   疏散速度   量化指标  

摘要： 城市交通枢纽综合体具有结构体型大、形式复杂、功能多样的特点，震后其交通流线对内部人员紧急逃生和避难至关重要。已有研究结合人员的基本行为模拟方法，通过分析构件损伤、对应设置障碍物的方式模拟震后人员疏散过程，对震后建筑疏散环境变化考虑不充分，忽略了建筑构件不同损伤状态下速度的变化，且缺少量化综合体建筑震后交通流线功能的评估指标。本文提出了一种综合体建筑震后交通流线功能损失量化评估方法。该方法基于构件易损性分析，建立了非结构构件不同损伤状态下的人员最大疏散速度折减模型，通过分析震后综合体不同空间位置处人员疏散的最大速度，考虑门构件破坏对人员疏散活动的延迟，建立震后疏散场景及模拟方法，并构建了震后综合体内交通流线功能的量化指标。通过工程需求参数扩充，考虑构件损伤等不确定性，提出了综合体建筑震后内交通流线功能量化评估方法。将该方法应用于某城市综合体，结果表明提出方法可以反应出地震作用下各楼层和区域的交通流线损失变化情况，并识别对结构整体疏散影响较大的薄弱楼层，对综合体震后功能损失评估提供参考。

摘要： Quadruped robots offer distinct advantages in navigating challenging terrains due to their flexible and shock-absorbing characteristics. This flexibility allows them to adapt to uneven surfaces, enhancing their maneuverability. In contrast, rigid robots excel in tasks that require speed and precision but are limited in their ability to navigate complex terrains due to their restricted motion range. Another category of robots, known as soft robots, has gained attention for their unique attributes. Soft robots are characterized by their lightweight and cost-effective design, making them appealing for various applications. Recent advancements have made significant strides in practical control strategies for soft quadruped robots, particularly in diverse and unpredictable environments. An emerging approach in enhancing the autonomy of robots is through reinforcement learning. While this approach shows promise in enabling robots to learn and adapt to their surroundings, it necessitates rigorous training and must exhibit robustness in real-world scenarios. Moreover, a significant hurdle lies in bridging the gap between simulations and reality, as models trained in idealized virtual environments often struggle to perform as expected when deployed in the physical world. This thesis aims to address these challenges by optimizing the control of soft quadruped robots using a model-based reinforcement learning approach. The primary goal is to refine the gait control of these robots, taking into account the complexities encountered in real-world environments. The report covers the implementation of model-based reinforcement learning, including simulation setup, reward design, and policy refinement. Results show improved training efficiency and autonomous behavior, confirming the method's effectiveness in enhancing soft quadruped robot capabilities. It is important to note that this report provides a concise summary of the thesis results due to the word limit imposed by the Depar

关键词： 悬架   制动   转向   一体化控制   全局最优  

摘要： 随着汽车智能化的发展趋势，对汽车底盘系统的控制性能提出了更高的要求，现有研究中大多采用底盘部分子系统单目标控制，这无法实现车辆性能全局最优。本文以分布式驱动电动汽车的半车底盘系统为研究对象，开展了对底盘纵-横-垂一体化控制的研究。首先，建立了车辆系统动力学模型；其次，为了保证整车获得良好的行驶平顺性、制动性以及横向稳定性，基于分层控制原理，设计了基于线性二次型最优化控制的底盘一体化控制器，以子系统各性能指标加权平方和的积分最小为目标，并应用层次分析法确定了控制器加权系数，实现底盘多系统的一体化协调最优控制；最后，基于仿真软件，分别搭建悬架、制动、转向子系统控制器来进行对比分析。仿真结果表明，所提出的底盘一体化控制策略的车辆，其行驶平顺性、制动性以及横向稳定性皆优于采用部分子系统控制的车辆。

摘要： Virtual reality (VR) is stated to be a key technology of the next decade with huge growth potential and is expected to transform many areas of business as well as daily life [73]. Thanks to technological advances in hard- and software, over the re- cent years, VR is getting used more frequently and moved from being solely a niche, experimental and expensive gadget to being a more widespread and mature (enter- tainment) device. Furthermore, it emerged as a serious and highly beneficial tool for various professional applications, which significantly enlarges the target group and user base. The application domains for VR are manifold and range from industry to entertainment and the scientific community. One concrete example is the virtual exploration of environments that are difficult or impossible to visit in person, e. g., in the field of archaeology and cultural heritage [53, 182]. Other examples are virtual 3D data/object inspection, e. g., in the medical, digital marketing, or architectural areas, and highly immersive and presence-inducing communication/telepresence, e. g., in healthcare or office/work settings. Additionally, VR is a natural fit for teach- ing and education tasks; either in industry settings, healthcare, or school. The main benefit of VR is that, with the help of innovative input and output devices, such as head-mounted displays, and stereoscopic vision, users can view, explore, and act in arbitrary computer-generated 3D environments in a more immersive and natural way than by looking at a simple 2D screen. Ideally, the users get a feeling of presence – as if they were actually there [152]. To that effect, a general goal is to make the en- vironments and interaction metaphors as realistic and intuitive as possible, though this is not always a necessity. The combination of VR and multi-user architectures promises to be especially beneficial, as it enables multiple (remote) people to enjoy the advantages of VR, in- teract with each other, and collab

关键词： 冰浆   管道   大管径   含冰率   阻力系数   雷诺数   Blasius  

摘要： 分别针对DN50和DN802种大管径管道开展了冰浆流动阻力特性实验研究,实验均处于湍流。实验发现:在低雷诺数下,冰浆阻力系数远大于适用于纯水单相流的Blasius关联式计算值,且含冰率越大,阻力系数越大;而在高雷诺数下,冰浆的阻力特性符合Blasius关联式,不同含冰率下的阻力系数都与纯水一致;含冰率和管径对冰浆阻力系数何时进入Blasius曲线有影响,含冰率越大、管径越大,则开始进入Blasius曲线的雷诺数越大;相较于直管,弯头的临界流速更高,更容易出现堵塞,且含冰率越大,临界流速越大。

关键词： CMOS传感器   光学变焦镜头   视频拍摄   长焦   电影镜头   一体机   场景模式   视频处理  

摘要： 佳能(中国)有限公司最新发布的室内4K摄控一体机新品CR-N100搭载1/2.3英寸CMOS传感器、视频处理平台DIGIC DV6等核心元器件,可实现4K/30P高画质视频拍摄。同时搭载了相当于29.3mm-601mm焦距的20倍光学变焦镜头,可以支持从广角到长焦等各类场景的拍摄需求。CR-N100还采用了在专业摄像机中高速、高精度的混合自动对焦技术,并配备了“人像”“运动”“低光”和“聚光”4种场景模式。