Ischemia-reperfusion injury (IRI) is an inherent issue in organ transplantation. Because of the allograft shortage, more and more extended criteria donor (ECD) organs are used, unfortunately these grafts are more susceptible to IRI. Although machine perfusion technology has brought hope to alleviate IRI, this technology is still unable to eradicate IRI-related organ damage. Ischemia-free liver transplantation (IFLT) can completely avoid IRI, thereby improve graft function and recipient outcome, and allow to expand organ pool. This review summarized the latest progresses in IFLT, and speculated the future development of this concept.
Global climate change has intensified the water cycle, leading to frequent extreme precipitation events, posing a significant threat to railway infrastructure and safety operations. Based on the analysis of past and future precipitation changes in China, this study investigates the impact of climate change on railway safety operations. The study reveals the following findings: (1) Under the influence of the intensified East Asian summer monsoon and the northward shift of the subtropical high during the 2017–2021 compared to the 2012–2016, precipitation has significantly decreased (120 mm) in the regions south of the Yangtze River and South China, while it has increased (60 mm) in the regions from the eastern of Northwest China to the middle and lower reaches of Yangtze River; The operational precipitation risk has decreased for Urumqi, Lanzhou, Qinghai-Tibet Group, Xi’an, and Wuhan railway bureaus (abbreviated as Bureau), while it has increased for Nanchang, Chengdu, Zhengzhou, Shanghai, and Shenyang Bureaus. Particularly noteworthy is that despite a decrease in total annual precipitation for Nanchang bureau (15.3 mm/a), the frequency of intense precipitation events has increased, leading to an increased operational precipitation risk. (2) During the 21st century, under high (SSP5-8.5), medium (SSP2-4.5), and low (SSP1-2.6) forcing scenarios, all projections indicate that most of the China will experience an increasing trend in precipitation, with significant increases in precipitation observed in the regions south of the Yangtze Rive, South and Southwest China. The higher the greenhouse gas emissions, the more pronounced the increasing trend in precipitation. (3) Compared to the 20th century, under high (SSP5-8.5), medium (SSP2-4.5), and low (SSP1-2.6) forcing scenarios, all projections indicate that the total annual precipitation hours, railway inspection, speed limit, and closure risk hours have all increased on a national scale during the 21st century. The operational precipitation risk for railways has also increased. The higher the alert level for railway precipitation (precipitation < inspection < speed limit < closure), the higher the proportion of risk hours compared to the 20th century. By the late 21st century, the railway inspection, speed limit, and closure risk hours have increased by 175%, 463%, and 647%, respectively, compared to the 20th century.
Next Generation Train Control System (NGTC) based on train-train communication can efficiently realize train tracking control through constant distance strategy. How to ensure the stability of the platoon with the control strategy is very crucial since the leader train action is random in the platoon control. Based on Stochastic Priced Timed Game (SPTG), we propose a train-train communication control strategy modeling and verification method. Firstly, according to the control strategy's requirements, a platoon control model including a leader train and follower trains are established and the stability are verified by SPTG automata. Secondly, using time expansion as the cost function, the optimal operation strategy of the platoon is obtained through combination of the cooperative game of the platoon's SPTG automata model and Q-learning. Finally, the stability optimization objection of the platoon is simulated in single-train operation, two-train operation and multi-train operation tracking scenarios. Compared with the random operation of the platoon, the result shows that this method can make the platoon stability error smaller.
技术在养老领域的应用一直是研究人员关注的焦点,基于对老年群体生理和认知层面自然衰老规律,梳理了适老化设计的研究方法的演化与发展,总结了更具人文关怀的科技适老化设计要素.对智能技术支持老年人拍照、运动和居家照护的3个场景进行了设计调研,挖掘了设计过程中要关注的发展方向.分析表明,在交互设计方面,应充分考虑老年人的感官状态,采用简洁友好的界面和多模态交互方式;在人文关怀方面,关注老年人对于科技的接受程度和使用时的情感体验,有助于老年人更好地融入数字化时代.
表面光催化材料广泛用于表面自清洁、污水处理、水制氢等领域.特别是复合半导体纳米材料,利用p-n结原理可以大幅度提高表面自由电子和电子空穴浓度,从而提高吸收太阳光的能力,具有广阔的应用前景.阐述了纳米光催化材料领域的研究进展,以及在食品包装、医疗器械、交通设备及建筑材料领域抗菌自清洁的应用前景.
Some critical aspects of metaverse are briefed. The significance of immersion to metaverse is highlighted. Efforts to improve the sense of immersion are investigated. The principles of some immersive display technologies including head-mounted display（HMD）, head-up display（HUD） and large size display are introduced and the corresponding prospects are envisioned.The importance of immersive interaction on metaverse is analyzed. Values of computer graphics, artificial intelligence and machine vision for metaverse are induced. The potential applications of metaverse are predicted based on the mentioned features.
随着人工智能、物联网等技术的发展,家居智能化成为新趋势.在购物消费、日常娱乐中,美妆行业表现出了巨大的市场潜力,美妆领域的智能化亦成为一个有趣的研究方向.围绕未来人居中的智能美妆系统,从基于镜面的人机交互设计、智能美妆相关算法、数字化妆镜系统相关交互技术3个方面,综述了国内外相关研究进展,分析了未来数字化妆镜系统的应用场景,总结了数字化妆系统的搭建思路与交互方案.
随着技术革命和全球化的不断深入,每一位学习者需要不断通过终身学习迭代自己的知识体系才能成为具有竞争力的未来人才.对终身学习的概念和定义进行了历史沿革梳理,并对终身学习的内涵与外延进行了定义.论述了终身学习理念与未来人才培养之间的关系,讨论了终身学习理念下如何进行人才培养.基于终身学习的理念与人才培养实践探索,阐述了如何建构终身学习理念下的人才培养体系.
睡眠科学和神经科学研究已取得巨大进展,对梦的研究也有了更深入的理解,但从艺术与神经科学交叉的角度进行梦的疗愈功能的探索尚显不足.梳理了以情绪为中心的梦境疗愈功能的相关研究进展,并介绍了清华大学未来实验室进行的梦境抽象艺术形式的探索.在梦境文化和科学研究背景下,试图重新定位科学与艺术融合下梦境研究的日常实践,结合心理学、睡眠科学、艺术学的相关研究成果交叉探索,重启梦境生成艺术对健康疗愈的重要方向.
介绍了人工嗅觉感知技术的概念,梳理了仿生类和化学分析类的人工嗅觉技术发展脉络;以清华大学未来实验室嗅觉计算组在人工嗅觉与嗅觉计算方面的研究工作为案例,阐述了该领域从人工嗅觉技术到嗅觉计算技术的发展趋势.分析了当前面临的技术挑战和可能的解决路径,展望了嗅觉计算在智能家居、智慧农业、医疗健康等行业的落地应用.
多学科交叉与融合是科学研究的重要特征之一,特别是在当今其更是科技发展和社会创新的必由之路.清华大学未来实验室从成立伊始就致力于打破学科壁垒,开展学科交叉与设计创新领域的前沿探索.结合未来实验室的几个学科交叉研究探索,介绍了基于人工智能的通用嗅觉计算理论与方法研究、未来材料与设计研究、智慧人居设计创新研究、无障碍设计创新研究、适老化服务设计研究、终身学习的理论与方法研究等相关领域的主要研究内容、国内外研究现状、未来实验室目前的研究进展以及对未来的展望和建议.
在高温固体氧化物燃料电池等器件中,气/固界面对电极反应性能及器件寿命有显著影响.因此,高温气/固电化学界面的精准调控和原位表征是新能源器件中材料研究与开发的一个核心方向.回顾了应用于高温电化学基础研究与器件领域中的高温气/固界面的制备调控的发展历程,总结了发展高温气/固界面原位动态表征的必要性及近年来原位表征的发展现状,指出了更精细的高温气/固界面研发的挑战.结合当前多学科发展方向,建议在未来的研究中提升界面调控的精确度至原子尺度,研发更多适用于高温气/固界面的原位表征方法,并结合运用机器学习等新的数据科学研究方法等.
随着人工智能、物联网、大数据等科技的迅猛发展,智能家居正式进入了3.0时代,深度依赖用户大数据进行深度学习和数据挖掘,迫切需要面向智能家居的智能交互、智能感知和复杂决策的新技术新方法作为支撑.综合国内外前沿相关研究,提炼出未来智能家居所需要的3大要素:"感知""思考"和"执行".并以此为脉络,综述了国内外智能家居前沿平台的研发进展,评议了智能家居环境中的数据采集和特征提取研究、智能家居场景下的智能感知研究、面向智能家居的多模态人机交互与创新场景研究的相关成果,介绍了清华大学未来实验室在智能家居领域的相关研究工作.
盲人可以通过盲文或读屏软件来学习理解文字内容,但目前缺乏帮助盲人有效学习和理解图形信息(例如数学中的几何知识、物理中的电路知识以及医学知识中的经络分布等)的工具和设备.从触觉及触觉显示设备的视角,针对盲人的触觉认知研究,剖析了盲人对图形的触觉认知机理,设计开发了触觉图形显示终端设备,并通过用户实验,验证了该设备的易用性.该设备采用创新的结构设计,实现了良好的触觉认知体验和相对低廉的成本控制,不仅能够动态生成布莱尔盲文和丰富的触觉图形信息,而且可以作为盲人学习、工作与生活的有效工具.
以国家创新体系理论为研究背景,在充分采集行业主管部门公开数据基础上,运用抽样调查和典型调查方法,测算出截至2020年底中国科技工作者总量为5835.78万人,人才规模庞大,但人才强度仍有较大提升空间.结果发现:青年已经成为中国科技工作者的主体,但其创新创造活力正面临诸多制约;本科以上学历者已经成为中国科技工作者主体,但战略科学家与一流创新人才依然匮乏;中国科技工作者的专业结构与经济社会高质量发展的适配度有待提高,保持学历教育与职业教育的合理结构是紧迫任务;中国科技工作者的身份认同感和职业辨识度还不高,弘扬科学家精神,增强职业荣誉感使命感还需持续发力.
葡萄叶片黄化严重影响葡萄果实的产量品质等经济性状,制约了葡萄产业的发展.为了厘清黄化现象的影响因素,将黄化现象发生原因主要分为病理性黄化和生理性黄化两大类.病理性黄化主要指植原体和病毒病引起的黄化,生理性黄化原因主要归纳为盐胁迫和碱胁迫.盐胁迫导致的叶片黄化主要由于单盐毒害作用降低叶绿素的合成引起,碱胁迫引起的黄化主要由于土壤碱性条件诱导NH4-和HCO3-积累造成植株中铁元素受阻引起.总结了叶片黄化对植株产生的影响、防治和矫正技术、葡萄抗缺铁生理机制以及抗缺铁品种的筛选成果,指出当前关于葡萄叶片黄化相关研究的不足.
野生牡丹为中国特有植物,是培育优异牡丹品种的重要资源.针对野生牡丹资源破坏严重,多数野生种处于濒危状态的现状,基于文献调研、原生境实地考察、电话咨询及团队对野生牡丹长期繁育的研究,总结了野生牡丹分类、目前分布区域和存在数量及其在育种中的应用.同时,综述了野生牡丹起源进化和油用与食用价值开发等方面研究进展,结合野生牡丹收集保存的现状和本团队野生牡丹研究进展,提出了具体保护策略.
为阐述蔬菜等经济作物珍稀濒危资源面临收集保护技术匮乏和保护体系不完善等瓶颈问题,介绍了主要经济作物蔬菜、果树、茶叶、花卉、热带作物的珍稀濒危资源及其保护、监测和利用现状,分析了其主要的濒危机制,并提出了主要经济作物珍稀濒危种质资源的保护策略.
In order to explore the present situation and development trend of science and technology security research, this paper makes comprehensive analysis and comment on the research of science and technology security at home and abroad from the elements, structure, function and external environment of science and technology security based on system theory. The research shows that science and technology security has strong integrity, hierarchy and linkage, and future research should focus on the governance of science and technology security, the construction of science and technology security early warning and monitoring system, the impact and evaluation of science and technology security on the overall national security.
随钻超声井眼成像技术是当前随钻测控领域的前沿技术,可以在随钻工况下实时生成高分辨率的井眼图像,能够准确反映井眼形状,识别裂缝、孔隙、层理等特征,在监测井眼工程状况和质量方面发挥着重要作用.阐述了随钻超声井眼成像系统的成像原理及构成要素,综述了发展历程及现状,分析了国外最新研发的随钻超声井眼成像系统的技术特点,总结了随钻超声井眼成像技术未来发展趋势,探讨了随钻超声井眼成像领域在仪器设计及发展的方向.
