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991.
针对传统数学规划方法处理BRT网络系统优化存在的局限性,提出了一类直达乘客量最大化的BRT网络规划问题并建立了数学模型。设计了该优化模型的禁忌算法。多次仿真实验结果表明模型合理,算法有效。 相似文献
992.
993.
发达国家进入城市化后,建筑师们为解决由此而产生的城市低收入阶层的住房问题进行了早期探索和研究。通过低收入阶层公共住宅设计课题的提出到实践历程的分析,为我国解决这一复杂问题提供理论支持和实践经验。 相似文献
994.
《Thin solid films》1987,147(2):143-152
Low pressure plasma-sprayed MCrAlY overlayer coatings are used for surface protection on superalloy components for gas turbine engines. In this work, an NiCoCrAlY alloy, PWA 276, deposited as thick plates by low pressure plasma spraying was studied in constant load creep-rupture tests conducted in air and vacuum at 660 and 850°C for various stresses. In addition, some specimens were pre-exposed in air or vacuum for 100 h at 1050°C prior to testing in air.At 660 and 850°C, rupture lives were two to three times longer in air than in vacuum. The second-stage creep rates were independent of test environment. However, during tests in air, tertiary creep began later, progressed at a lower rate and continued to a greater strain at fracture than during tests in vacuum. In comparison, specimens pre-exposed in air at 1050°C exhibited a greater time to the onset of tertiary creep, but the same strain at fracture as as-machined specimens also tested in air. Failure in both environments was essentially by void growth; however, during tests in vacuum many surface cracks extending from micropores also formed and linked up with the internal voids. Testing in air apparentlu increases the ductility of the alloy surface, preventing stable surface crack growth until the alloy ruptures because of a reduction in the load-bearing area. A decrease in the second-stage creep rate which occurred on pre-exposure at 1050°C, whether in air or vacuum, has been attributed to precipitation hardening. A precipitated phase within the λ phase was observed by scanning and transmission electron microscopy but is not yet identified. 相似文献
995.
996.
针对河口首站原油分离出来的污水存在悬浮物(SS)、细菌、硫化物含量严重超标、污水呈臭"黑水",无法满足油田注水系统要求的系列问题,作者研究了脱硫净化和杀菌技术,通过药剂筛选和现场试验,说明了药剂对污水处理的巨大效果,同时配合污水过滤的生产工艺,形成了一套实用高效的污水综合处理技术,处理后的水质达到了油田注水B2级标准要求,满足了油田生产要求. 相似文献
997.
998.
提出一种改进的射门算法.通过路径规划,使得机器人沿着平滑的轨迹将位姿调整到射门状态,然后,根据位姿变化最小的原则,从对方门线的坐标点中选择射门目标点,以圆弧路径完成射门过程.试验表明,算法可以提高射门成功率. 相似文献
999.
Yaxin Wang Binghong Xu Sen Ma Hao Wang Luqing Shang Cheng Zhu Sheng Ye 《International journal of molecular sciences》2022,23(4)
As the etiological agent for the coronavirus disease 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) challenges the ongoing efforts of vaccine development and drug design. Due to the accumulating cases of breakthrough infections, there are urgent needs for broad-spectrum antiviral medicines. Here, we designed and examined five new tetrapeptidomimetic anti-SARS-CoV-2 inhibitors targeting the 3C-Like protease (3CLPro), which is highly conserved among coronaviruses and essential for viral replications. We significantly improved the efficacy of a ketoamide lead compound based on high-resolution co-crystal structures, all-atom simulations, and binding energy calculations. The inhibitors successfully engaged the catalytic dyad histidine residue (H41) of 3CLPro as designed, and they exhibited nanomolar inhibitory capacity as well as mitigated the viral loads of SARS-CoV-2 in cellular assays. As a widely applicable design principle, our results revealed that the potencies of 3CLPro-specific drug candidates were determined by the interplay between 3CLPro H41 residue and the peptidomimetic inhibitors. 相似文献
1000.
Actin-associated proteins (AAPs) act on monomeric globular actin (G-actin) and polymerized filamentous actin (F-actin) to regulate their dynamics and architectures which ultimately control cell movement, shape change, division; organelle localization and trafficking. Actin-binding proteins (ABPs) are a subset of AAPs. Since actin was discovered as a myosin-activating protein (hence named actin) in 1942, the protein has also been found to be expressed in non-muscle cells, and numerous AAPs continue to be discovered. This review article lists all of the AAPs discovered so far while also allowing readers to sort the list based on the names, sizes, functions, related human diseases, and the dates of discovery. The list also contains links to the UniProt and Protein Atlas databases for accessing further, related details such as protein structures, associated proteins, subcellular localization, the expression levels in cells and tissues, mutations, and pathology. Because the actin cytoskeleton is involved in many pathological processes such as tumorigenesis, invasion, and developmental diseases, small molecules that target actin and AAPs which hold potential to treat these diseases are also listed. 相似文献