摘要：Increasing attention has been paid to the air pollution more recently. Smog chamber has been proved as a necessary and effective tool to study atmospheric processes, including photochemical smog and haze formation. A novel smog chamber was designed to study the atmospheric photochemical reaction mechanism of typical volatile organic compounds(VOCs) as well as the aging of aerosols. The smog chamber system includes an enclosure equipped with black lights as the light source, two parallel reactors(2 m^3 of each) with separate control of light source and temperature, with a series of coupled instruments for online monitoring of gas phase and particle phase reactants and products. Chamber characterization, including air source stability, effective light intensity, temperature stability, as well as gas phase and particle phase wall losses, were carried out before further research. The results showed that our smog chamber systems developed by other domestic and international groups. It was also observed that the wall loss of aromatic VOCs varied with different functional groups as well as the isomerism. The results of preliminary simulation experiment from styrene-NO_x demonstrated that the chamber can be well utilized to simulate gas-particle conversion progresses in the atmosphere.

摘要：This paper reports a comprehensive study on the observed and projected spatiotemporal changes in mean and extreme climate over the arid region of northwestern China, based on gridded observation data and CMIP5 simulations under the RCP4.5 and RCP8.5 scenarios. The observational results reveal an increase in annual mean temperature since 1961, largely attributable to the increase in minimum temperature. The annual mean precipitation also exhibits a significant increasing tendency. The precipitation amount in the most recent decade was greater than in any preceding decade since 1961. Seasonally, the greatest increase in temperature and precipitation appears in winter and in summer, respectively. Widespread significant changes in temperature-related extremes are consistent with warming, with decreases in cold extremes and increases in warm extremes. The warming of the coldest night is greater than that of the warmest day, and changes in cold and warm nights are more evident than for cold and warm days. Extreme precipitation and wet days exhibit an increasing trend, and the maximum number of consecutive dry days shows a tendency toward shorter duration. Multi-model ensemble mean projections indicate an overall continual increase in temperature and precipitation during the 21 st century. Decreases in cold extremes, increases in warm extremes, intensification of extreme precipitation, increases in wet days, and decreases in consecutive dry days, are expected under both emissions scenarios, with larger changes corresponding to stronger radiative forcing.

摘要：针对舰载固定翼无人机(UAV)动态精确回收过程中的制导控制技术开展研究,提出基于分段策略的舰载无人机精确回收引导方法,完成了动态撞网回收控制系统方案设计与集成测试。通过数值迭代方法预测触网时间实现回收航线的在线规划,在回收中段采用基于引导点的非线性制导算法对航线进行精确跟踪,在回收末段基于经典比例导引及纵横解耦策略设计了三维空间末制导律,实现了针对动基座回收的撞网点精确控制。通过系统仿真和飞行试验证明了分段制导策略与各阶段算法的有效性,结果表明:回收航线规划方法简单有效、适应性强,制导控制算法对于航线的跟踪偏差小于0.5 m,高度控制的稳态精度优于0.5 m,动态撞网回收的末端精度优于0.8 m,各阶段的制导控制精度满足无人机动态撞网需求,所提方法适于工程应用。

摘要：我国空间站已经进入建造阶段,开启了载人航天新征程.根据我国空间站试验任务需求,自主设计研制了空间站核心舱大气密度多向探测器,探测获取空间站运行高度上大气密度的时空分布变化,为空间站的飞控管理、精密定位和分析服务,并积累长期自主探测数据,为地球空间中性环境物理模式和效应研究提供基础数据.本文主要介绍了探测器的探测目标、载荷配置、长寿命设计等情况,同时使用在轨探测初步结果进行了运行轨道上大气密度的变化特性分析,呈现出日侧和夜侧轨道圈上大气密度变化,2021年9月11~14日和11月19~22日空间环境平静期日侧和夜侧的峰谷比在2~3之间;2021年11月4日的较强地磁暴期间实测大气密度峰值增加至1.966倍,而模式值峰值增加至1.483倍,磁暴恢复期模式为6h,而实测数据晚12 h;2022年3月13日的磁暴事件期间,实测大气密度增加至1.424倍,模式值增加至1.250倍,大气密度全球抬升从南半球开始,扩展到北半球,与2021年11月4日扰动源位置相反;统计了2021~2022年期间6次磁暴事件,大气密度抬升比例与磁暴强度、持续时间呈正相关;2021年12月11~31日空间环境平静期,实测值和模式的日均值相对偏差小于10%.实测数据与模式数据相比,增变幅度大、传播范围广、持续时间长、响应更加灵敏.实测数据将为地球空间环境物理与效应研究提供长期自主数据库.

摘要：This paper discusses the methods of establishing risk criteria for dams and reviews the application of dam risk criteria for individuals and societies in different countries or districts. Given the conditions in China and considering the public safety and acceptance of dam risk, historical dam break data and current design standards, individual and societal risk criteria for dams are proposed. The tolerable dam risk criteria for individuals should be set to 10-5-10-7 per annum based on project scale, for ex- ample, approximately 1.0xl0 7 per annum, which corresponds to a reliability index of 4.2 based on a 100-year lifespan for a first-class or large project. The societal limit for risk tolerance for dams should be set to approximately 10-3-10-5 per annum, corresponding to the fatality range from 1 to 100 and be horizontally extended to 1000, and F-N curves are proposed. It was also found that the reliability indices of Chinese Standard （GB 50199-2013） and Eurocodel （2002） are different, but they have the same level of safety measured by the annual probability of failure. The research results have significance for establishing dam risk criteria.

摘要：20世纪80年代以来,我国文化创意产业的发展不仅面临全新快速发展的全球化环境,而且身处地方社会独具的重叠和收缩的现代化进程之中。步入新世纪,文化创意产业区空间实践发展迅猛,但存在产品定位趋同与同质化建设、资源分散等问题。为探索城镇地域涌现的文化创意产业区空间可持续发展路径,文章以外部全球化与内部地方性发展水平为双重线索,对长三角地区典型个案的发展特征进行评价,通过解析制度要素演进机理进而揭示地域空间发展格局。文化创意产业的健康增长需要内外要素间的互动,增长曲线的峰值决定了一个最优的"地方-全球化"要素配比。保持地域禀赋的要素配置格局相对于全球化范式的弹性适应能力是政策创新与建构地方制度整合机制的关键。地方性要素作用途径分异致使多样化空间载体涌现,因而需要地方政策采取不同策略进行引导。

摘要：产品用户在企业建立的开放式创新平台上发布创意,认可度表示创意是否受到欢迎,是衡量创意质量的重要指标。通过创意文本传达的信号,可以快速高效识别有价值的创意。本研究基于信号理论,从信息和情感两个方面提出五种语言信号,据此构建语言信号对创意认可度影响的理论模型,并采用Salesforce TrailBlazer Community的10818条创意验证模型和假设。结果表明,信息独特性、文本可读性和情感效价对创意认可度产生正向影响,主题多样性及情感主观性对创意认可度产生负向影响。本研究结论有助于开放式创新平台管理者加深对创意文本特征的认知,制定更为完善的运营策略。

摘要：新年画运动是新中国美术史上第一个政令化的美术运动,发始于1949年底。早在抗日战争时期,年画就成为中国共产党宣传革命的工具,并取得了一定的成绩。新中国成立后,共产党再次选择了最具有群众基础的年画进行改造,使其成为宣传新中国、建立新的社会意识形态的艺术样式。由于政策的鼓励,大批艺术家、文艺团体投入新年画的创作中,产生了一批具有鲜明时代特征和独特艺术语言的经典作品。以政治宣教为主要功能的新年画运动在20世纪50年代取得了辉煌的成就,并影响了新中国美术界其他画种的发展。但是,随着政治宣教功能被无限放大,艺术家的创作被过分限制和程式化,新年画运动失去了继续发展的动力和空间而逐渐走向衰落。本文以这一时期中国国家博物馆藏新年画文物为据,探讨新年画运动的历史发展脉络及其特点。

摘要：三峡工程混凝土重力坝左岸1~5#坝段深层抗滑稳定是三峡工程水工设计关键技术难题之一.其中节理在主滑方向的连通率是确定强度指标的决定性因素.本文作者研究团队通过现场实测的近2000条节理产状几何参数和相应网络模拟技术,获得了在主滑方向的连通率为70%左右的结论;证明了上限解(即Sarma法)和规范规定的"等K法"的等效性,从而将双滑面模式扩展为更具广泛实用意义的折线型滑面的二维抗滑稳定分析方法;同时进行了可靠指标和分项系数方法的计算.抗滑稳定分析成果表明,如果坝体单独抗滑,设计要求复核的两种滑移模式均无法满足允许安全系数规定值.如果厂、坝联合受力,则相应两种滑移模式的安全系数均达到了允许值.上述研究成果为1~5#坝段的设计提供了合理性依据.本文介绍蓄水后1~5#坝段原型观测成果,以验证相关研究成果.

摘要：圈叠胎作为古代漆器胎体的一种特殊工艺,在五代、宋元应用较为普遍,之后便逐渐销声匿迹,《髹饰录》等古代文献均没有任何记载。现今漆艺界对圈叠胎的认知基本都来自于吴福宝团队的研究,且侧重工艺技术,疏于源流考证。本文通过推导论证,认为圈叠胎工艺始发于唐代早期,瓷器的普及迫使漆器革新技术,器型仿造的需要促使胎体产生变革是诱发其产生的外部原因。至明清时期,漆器逐渐由实用转向欣赏,圈叠胎也随之走向衰落。