大学育人的市场逻辑及其超越

人力资本理论自20世纪60年代开始风靡,深刻改变世界各国的公共决策,也直接促进了高等教育规模的迅速提升,但是,其背后的市场逻辑却导致大学育人出现体系失衡、主体性遮蔽、想象力被抑和公平受损等问题。大学与市场的关系是合作而不是迎合,高等教育要为市场提供人力,也要为国家培育公民、为学术培养人才、为个人提升内涵,不可偏废其一。当今世界处于“百年未有之大变局”,中国正面临复杂的国际形势,竞争加剧、创新不足、人口老化等问题接踵而至,大学必须致力于社会的长期稳定发展。在新时代背景下,中国大学育人要在主体意识、内涵发展和评价标准等方面做好价值坚守,要从理念、结构、方式和内容等要素出发进行系统创新的探索。     

SKY数控系统的发展战略研究

叙述当今世界数控技术发展的背景,阐述了“同一起跑线”的发展观点和数控技术创新的必要性和可能性,介绍ＳＫＹ数控系统的设计思想、结构体系、特点和发展趋势以及南京四开电子企业有限公司的数控产品的应用情况,论述拥有数控技术知识产权的重要性。     

极限尺寸判断原理及应用

由于形状误差的存在,必然影响完工后零件的装配及配合性质要求。极限尺寸判断原则,不仅提供了解决这类问题的依据, 而且统一了人们对尺寸的认识, 同时也是量规设计的理论基础。     

Ruthenium Nanoparticles on Cobalt‐Doped 1T′ Phase MoS2 Nanosheets for Overall Water Splitting

2D MoS₂ nanostructures have recently attracted considerable attention because of their outstanding electrocatalytic properties. The synthesis of unique Co–Ru–MoS₂ hybrid nanosheets with excellent catalytic activity toward overall water splitting in alkaline solution is reported. 1T′ phase MoS₂ nanosheets are doped homogeneously with Co atoms and decorated with Ru nanoparticles. The catalytic performance of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is characterized by low overpotentials of 52 and 308 mV at 10 mA cm^?2 and Tafel slopes of 55 and 50 mV decade^?1 in 1.0 m KOH, respectively. Analysis of X‐ray photoelectron and absorption spectra of the catalysts show that the MoS₂ well retained its metallic 1T′ phase, which guarantees good electrical conductivity during the reaction. The Gibbs free energy calculation for the reaction pathway in alkaline electrolyte confirms that the Ru nanoparticles on the Co‐doped MoS₂ greatly enhance the HER activity. Water adsorption and dissociation take place favorably on the Ru, and the doped Co further catalyzes HER by making the reaction intermediates more favorable. The high OER performance is attributed to the catalytically active RuO₂ nanoparticles that are produced via oxidation of Ru nanoparticles.     

浅谈具有自动排尘功能的高效转子粗滤器设计原理

目前国内所采用的空气滤清器在多尘环境中使用,如何使空气滤清器在多尘环境下工作过滤来改善发动机的运行环境,使发动机的使用寿命延长,提高工作效率,聍空滤器而言空滤器中预滤系统设计得是否合理是影响这一性能的重要因素。     

一种测量凸轮升程误差的新方法

提出一种在万能工具显微镜上利用自制测头等附件对圆柱凸轮升程误差进行接触法测量的新方法 ,介绍了测量原理及实现方法 ,分析了该方法的测量精度 ,并通过测量实例验证了该方法的可靠性和实用性     

基于二代小波和图像置乱的数字图像盲水印算法

针对基于第一代小波的多分辨率水印算法运算速度慢、图像的重构质量与变换时延拓边界的方式有关等不足,根据第二代小波变换的特点,结合Amold置乱算法,给出一种基于小波多级提升和水印图像置乱来实现的改进型多分辨率图像水印算法,并分别采用Haar、Db2、Db4、9/7小波进行仿真实验。结果表明,该算法不仅保持了传统小波多分辨率图像水印算法的优点,而且有效提高了处理速度,并弥补了传统小波多分辨率图像水印算法中当滤波器增长时,含水印图像质量下降的不足。     

Uncertainty Analysis of Conventional Water Treatment Plant Design for Suspended Solids Removal

An approach that links a Monte-Carlo simulation based reliability program with the water treatment process behavior and performance model is presented for uncertainty analysis of the conventional water treatment plant (WTP) design. The expected mass concentration of suspended solids (SS) in the effluent water is employed as a measurement of system reliability. The approach for uncertainty analysis of a WTP is illustrated with a hypothetical case study. The parameters contributing significantly to the variability of SS concentration in the effluent water are identified. From an operational viewpoint, the variability in effluent water quality resulting from uncertainty in the system parameters is investigated. Also, improvement in the reliability of WTP using modified design parameters is investigated along with its cost implications. From the results, a method to calculate a set of safety factors corresponding to various performance reliability levels is proposed.     

Differences in lifting strength profiles between experienced workers and novices at various exertion heights

This study compared lifting strength patterns between experienced workers and novices at various exertion heights. Twenty-one experienced workers and 21 novices were recruited to determine their static-lifting strength under various heights (10-150 cm in increments of 10 cm) using two exertion methods (vertically upward lifting, VUL, and toward body lifting, TBL). Testing posture was also recorded by a motion analysis system for comparing with the corresponding strength values.Results showed that strength during VUL were much higher than strength during TBL at 15 height positions (p < 0.001). Strength in all 30 task combinations showed no difference between the two groups except for the VUL at heights of 100-120 cm. On the average, strength exerted by novices during VUL was 4.57-7.61 kg lower than that of workers while lifting at 100-120 cm heights (all p < 0.05). The strength during TBL consistently decreased with increased heights of lifting. When workers performed VUL, the strength surprisingly remained nearly unchanged throughout the heights of interest. The postures adopted by workers during VUL were also highly differentiated from novices while performing near-floor positions, but the strength was equivalent to each other. This study demonstrated that the static-lifting strength of novices were significantly lower than those of experienced workers while upward lifting near the participant’s elbow height. It was concluded that workers tend to adopt a safer (i.e., more flexed knees) and more skillful technique than novices to generate forces, resulting in lower spinal loads during both methods of lifting.

Relevance to Industry

Many studies have established the human strength data based on student participants who do not have experience in manual materials handling. The present findings clearly suggest that lifting strength data collected on novices (e.g., on students) should be carefully applied in the task (re)design at the workplace as their strength profiles and the postures adopted during lifting differ from workers.     

基于提升小波变换的图像认证数字水印

目前基于小波变换的数字水印算法主要根据频域小波系数的幅值大小确定是否嵌入水印,这种算法的缺点是嵌入水印后的图像的视觉透明度不够好.该文提出了一种基于提升小波变换的盲水印算法,利用提升小波变换将原始图像进行多分辨率分解,利用低频部分系数来生成水印,基于密钥来选取高频部分的小波系数,并根据小波系数的奇偶性嵌入水印.在水印提...