变位斜齿圆柱齿轮的克隆设计与计算

当模数为1 mm而齿数又小于12的齿轮,肯定是变位齿轮。蜗杆和蜗轮,自然就是变位蜗杆和变位蜗轮。当要求克隆的变位齿轮和变位蜗杆、变位蜗轮与样品的变位齿轮、变位蜗杆、变位蜗轮的所有参数一致,而变位齿轮宽度又很窄时。这种窄小型变位斜齿圆柱齿轮的参数,在无法测量的情况下,如何仅根据变位齿轮的模数、齿数、中心距和齿顶圆的直径来确定变位斜齿圆柱齿轮的所有参数,进而确定变位蜗杆、变位蜗轮的所有参数。而要加工出克隆变位斜齿圆柱齿轮、变位蜗杆、变位蜗轮模具的型腔,就必须要制作加工它们的电极或拉刀。不能确定它们的所有参数,要制造出它们的电极、型腔和产品都会成为不可能的事情.所以,计算它们的参数是变位齿轮、变位蜗杆和变位蜗轮克隆设计的关键,它们的参数不正确,还会造成啮合间隙大,传动时噪声大,转动不平稳;齿根处会产生着根切现象,齿的强度差;负载时肯定会打掉有根切的齿而使齿轮无法使用。

Surface Treatment of Crl2MoV Steel towards Long-Life Cold-Work Dies

With the rapid development of the automobile industry in China, there is an ever-increasing demand for long-life cold working dies used for punching automobile components. However, the full potential of such advanced surface engineering technologies as PVD coatings and duplex surface treatments in cold work dies has not been realized. In the present study, Crl2MoV steel has been surface engineered by single PVD Ti/TiN coating and duplex treatment combining low temperature plasma nitriding (LTPN) with PVD Ti/TiN coatings. The properties of Ti/TiN coatings in terms of surface morphology, microhardness, load bearing capacity, bonding strength and wear resistance were evaluated by microhardness, scratch and wear tests. The experimental results show that PVD Ti/TiN coatings can significantly enhance the surface load bearing capacity (especially for duplex treatments) and wear resistance of Crl2MoV steel by more than one order of magnitude. This can be mainly attributed to the hard and well-adherent PVD Ti/TiN surface coatings and strong mechanical support of the LTPN sublayer. While two-body abrasive wear prevails for uncoated Crl2MoV, the micropolishing action of the counterface dominates in surface engineered material.

一种分布式层次化网络安全态势评估与决策模型

针对分布式网络环境下网络安全态势感知技术难以全面有效覆盖的问题,提出一种管理控制中心支撑下网络节点进行自主网络防御的层次化态势评估与决策响应模型,解决了局部安全防护不全面和难以细化操作的问题。仿真结果表明,模型能较好地反映网络的实时安全状况。

恶性肿瘤患者日间化疗与住院化疗医院感染情况及综合疗效比较研究

目的:分析恶性肿瘤患者日间化疗与住院化疗医院感染情况及综合疗效。方法:选取2022.1-2023.12月400例日间化疗恶性肿瘤患者为研究组,同期住院化疗恶性肿瘤患者400例为对照组,比较两组化疗期间感染发生率、不良事件发生率、临床疗效及生活质量评分。结果:研究组化疗期间感染发生率显著低于对照组(1.50%vs 6.00%,P<0.05)。研究组不良事件发生率显著低于对照组(11.00%vs 2.25%,P<0.05)。治疗后研究组患者KPS评分和ADL评分均显著高于对照组患者(P<0.05)。结论:日间化疗减少恶性肿瘤患者住院时间,降低化疗期间感染发生率和化疗相关不良事件发生率,改善其生活质量,但不影响化疗疗效。