摘要：论述了轮轨型面匹配对车辆/轨道动态行为和轮轨系统磨损接触疲劳的影响.介绍了铁路车轮型面优化设计的有关理论、技术和结果,分析、比较了各种方法在车轮型面优化中的应用及其存在的问题,并给出了相应的改进措施.结合车轮踏面的现有优化设计方法,提出了一种可以综合考虑接触应力、磨耗指数和临界速度等多个性能指标的车轮踏面优化方法,指出了优化过程中数学模型建立困难和求解速度慢等问题,并提出了相应的改进措施.

摘要：针对采用直线脉管制冷的超长线列红外焦平面器件杜瓦封装的需求,提出了一种弹性冷链的设计方案。介绍了超长线列焦平面器件及直线脉管制冷机的特点以及对冷链的力学、热学要求,针对超长线列焦平面杜瓦冷链的设计思路、设计方法进行了研究,针对某型号脉管制冷机及典型超长线列探测器的尺寸、工作温度等要求,采用局部弹性冷链方案,通过有限元仿真工具对冷链进行优化设计,使其能够满足设计指标要求。根据设计结果制作了冷链及测试杜瓦,对冷链温差、器件拼接基板温度均匀性及低温形变进行了测试,并通过振动试验对力学可靠性进行了验证。试验结果证明局部弹性冷链设计方案的正确性和可行性。

摘要：Backfill mining is one of the most important technical means for controlling strata movement and reducing surface subsidence and environmental damage during exploitation of underground coal resources. Ensuring the stability of the backfill bodies is the primary prerequisite for maintaining the safety of the backfilling working face, and the loading characteristics of backfill are closely related to the deformation and subsidence of the roof. Elastic thin plate model was used to explore the non-uniform subsidence law of the roof, and then the non-uniform distribution characteristics of backfill bodies’ load were revealed. Through a self-developed non-uniform loading device combined with acoustic emission (AE) and digital image correlation (DIC) monitoring technology, the synergistic dynamic evolution law of the bearing capacity, apparent crack, and internal fracture of cemented coal gangue backfills (CCGBs) under loads with different degrees of non-uniformity was deeply explored. The results showed that: 1) The uniaxial compressive strength (UCS) of CCGB increased and then decreased with an increase in the degree of non-uniformity of load (DNL). About 40% of DNL was the inflection point of DNL-UCS curve and when DNL exceeded 40%, the strength decreased in a cliff-like manner;2) A positive correlation was observed between the AE ringing count and UCS during the loading process of the specimen, which was manifested by a higher AE ringing count of the high-strength specimen. 3) Shear cracks gradually increased and failure mode of specimens gradually changed from “X” type dominated by tension cracks to inverted “Y” type dominated by shear cracks with an increase in DNL, and the crack opening displacement at the peak stress decreased and then increased. The crack opening displacement at 40% of the DNL was the smallest. This was consistent with the judgment of crack size based on the AE b-value, i. e., it showed the typical characteristics of “small b-value-large crack and

摘要：种子园的规划设计是林木育种的基础工作,在亲本数量不确定的前提下,最大限度避免种子园内无性系之间近交繁殖,保证种子园具有较高的遗传效益,是种子园设计的目标。以内蒙古红花尔基樟子松(Pinussylvestris ***)国家良种基地的1、1. 5、2代种子园樟子松无性系通过SSR等技术分析得到的不同亲本之间的遗传距离为数据支撑,考虑复杂的亲本关系,通过改进的智能优化算法进行种子园设计,并将最终结果与其他智能优化算法和传统算法的结果进行对比分析。结果表明:改进型果蝇算法的收敛速度和效果优于其他算法,由所有算法分别执行200次之后的对比结果中可见,其最大值低于其他算法的最小值。在完全随机算法设计方案中存在多处同一无性系分株相邻出现,遗传算法和改进型果蝇算法设计方案并无同一无性系分株作为近邻出现且改进型果蝇算法设计方案的优先交配优于遗传算法设计方案。结果表明,基于遗传距离处理亲本复杂的亲缘关系,采用智能优化算法进行方案配置,可以为高世代种子园设计提供参考。

摘要：以作为革命老区贫困县的宁冈县为例，探讨了具有旅游资源优势的贫困山区开发扶贫模式，通过把旅游业作为先导产业，并结合产业开发走出一条生产生活日用品的工业道路，强调“一村一品、一人一技”发展地方经济，生产相应旅游商品，可为老少边穷地区提供一条具有普遍意义的发展案例。

摘要：由于图像资料年代久远,目前学界对金丝彩冠的形制结构多有误解,有关其成因的研究亦鲜少涉及。本文以德安县博物馆藏“金丝彩冠”为研究对象,集诸多文献、图像与实物为依据,指出“金丝彩冠”同属南宋“如意小冠”品类之列,其如意形态并非两侧卷曲的镂空结构,而是冠表的一种平面化装饰;考证金丝彩冠的结构原貌,还原了冠体无簪孔但以簪阻隔脱落路径的巧妙固冠设计;通过梳理大量古籍和对比同一墓葬的纸质冥器,辨析出纸胎为之的“金丝彩冠”应为逝者生前之物,而非特制冥器入葬;金丝彩冠的成因由政策引导、资源优势等多重因素共同促成,它是“如意小冠”这一大类的缩影,代表了南宋时期妇女首服的流行风尚。

摘要：进气畸变实验是航空发动机气动稳定性评定的重要方法之一。为克服传统设计方法逼近目标畸变图谱准确性低、实验迭代次数多等缺点,提出基于丝网间距和多孔介质映射关系,采用Fluent设计目标图谱畸变网的设计体系。设计了稳态总压测试系统,完成了畸变发生器的实物设计及风洞试验,畸变指数误差小于1.5%。试验结果表明设计体系可以高精度、高效地模拟畸变要求。

摘要：在构建中职文化艺术类人才培养与地区文化产业发展耦合协调度模型的基础上,以京津冀区域为研究对象展开实证分析,发现2015-2019年京津冀地区与全国总体相比耦合协调度增速偏低,且北京市耦合协调度出现下降趋势。从中职文化艺术类人才培养数量、培养结构与培养质量三方面进行成因分析,提出促进京津冀中职文化艺术类人才培养与文化产业协调发展的建议:顺应文化产业发展需求,适当提高京津冀区域中职文化艺术类人才培养整体规模;结合自身特点与布局,北京市可考虑优化中职文化艺术类人才培养结构与质量;为促进区域协同发展,津冀应进一步完善中职文化艺术类人才培养体系。

摘要：鹦鹉洲长江大桥设计为三塔四跨钢-混结合加劲梁悬索桥,跨度布置为(200+2×850+200)m,两主跨主缆跨度均为850m,主缆矢跨比为1/9,边跨主缆跨度均为225m。三塔不等高,中塔为钢-混混合结构,高152m;边塔为混凝土结构,高126.2m。桥塔横向均为框架结构,塔柱之间均设置上下2道横梁。中塔混凝土下塔柱纵向采用台阶式的I形结构,钢上塔柱纵向采用人字形结构;边塔纵向采用I形塔结构。桥塔塔柱根据位置的不同分别采用单箱单室和单箱三室截面;横梁采用预应力混凝土结构。桥塔施工采用泵送混凝土工艺。分别对桥塔进行稳定及纵、横向静力计算分析,结果表明结构强度、刚度、稳定性均满足规范要求。

摘要：Hydrogen sulphide(H2 S)is a common air pollutant,which is produced in various industry ***,it is of crucial importance to detect H2 S in real *** fluorescent sensors were reported aiming at detecting H2 S in solution;however,the fluorescence sensing of gaseous H2 S has not yet been *** this work,we utilized the post-functionalized fluorescent film,MIL-100(In)@Eu3+/Cu2+film,realizing fluorescence turn-on sensing of gaseous H2 S at room temperature for the first time with the limit of detection as low as 0.535 ppm,which is comparable to some reported fluorescent probes for S2-ions and semiconductor based gaseous H2 S *** sensor was designed due to the strong affinity of H2 S with Cu2+.With the formation of CuS,the"antenna effect"between the ligand and Eu3+recovered,resulting in the fluorescence turn-on of Eu3+***,we proposed a new method to realize multi-colour anti-counterfeiting patterns with lanthanide ions ink,taking advantage of the extraordinary smooth surface and uncoordinated carboxylate groups within the MIL-100(In)film.