分解炉结构参数的优化设计研究

针对水泥生产中分解炉的结构参数优化设计问题,提出了一种利用分解炉虚拟样机结合神经网络、遗传算法及正交设计的方法,详细研究了它们之间的逻辑联系和在整体优化设计框架中的作用,同时以水泥生产中常见的双喷腾分解炉为例,对其结构参数进行了优化设计研究,给出了优化结果.该方法不仅建立了一套较为完备的分解炉系统仿真和分析的理论体系,为分解炉进一步的开发和设计提供了有利的工具,同时也为工程设计人员提供了一种优化思路.     

毫米波辐射对K562细胞作用机制研究

观察了毫米波辐射对K562细胞超微结构,钙离子沉淀分布和线粒体跨膜电位（△ψm）变化的影响,发现低功率密度的毫米波辐射可以引起多数细胞的细胞膜形态立即发生变化,同时引起内质网池极度扩张,边缘钙离子沉淀增多,辐射结束数小时内凋亡细胞逐步增多,表明低功率密度的毫米波辐射通过影响胞膜和内质网,引起胸内钙离子浓度升高从而诱导细胞凋亡。     

Effect of Cu surface segregation on the exchange coupling field of NiFe/FeMn bilayers

The NiFe/FeMn bilayers with different buffer layers (Ta or Ta/Cu) were prepared by magnetron sputtering. Results show that the exchange coupling field of NiFe/FeMn films with Ta buffer is higher than that of the films with Ta/ Cu buffer. We analysed the reasons by investigating the crystallographic texture, surface roughness and surface segregation of both films, respectively. We found that the decrease of the exchange coupling fields of NiFe/FeMn films with Ta/ Cu buffer layers was mainly caused by the Cu surface segregation on NiFe surface.     

叶螨危害对豇豆叶片超氧化物歧化酶及过氧化氢酶活性的影响

对豇豆（Vignasinensis）幼苗受朱砂叶螨（Tetranychus cinnabarinus Boisduval）危害初期超的歧化酶（SOD）、过氧化氢酶（CAT）活性的变化进行了初步研究,每片叶分别接虫0,20,40头,危害0－8d,结果表明,在测定期间,对照的SOD活性持续降低,2d时处理的活性明显上升,随后随渐降低,但始终不低0d的活性,处理与对照间的活性差异显著,且随虫口密度增大差异增大;在叶螨危害2d时,不同虫口处理的CAT活性均较对照升高,差异显著,随危害时间延长,CAT活性比对照降低,且虫口密度度大降低的幅度越大。     

浅谈公路工程施工设备管理

通过对目前公路工程建设中施工单位的现状及存在问题的分析,探讨了在市场经济条件下,如何更好更充分地发挥机械设备在公路工程建设中的作用,提出了公路工程施工机械设备管理方面的几点措施。     

直接频率合成技术在引信时间装定中的应用

小口径速射炮系统 ,通过炮口快速装定 ,达到对目标更高的毁伤概率。该装定系统在弹丸发射时 ,根据弹道参数解算出装定时间信息 ,然后将这一时间信息经编码、调制后向外发送。在弹丸飞离炮口的瞬间 ,将这一时间信息传输该引信 ,实现引信的实时炮口快速装定。该文通过对引信的装定系统进行分析 ,结合直接数字频率合成技术 (DDFS)的特点 ,将DDFS用于引信装定系统中 ,实现对编码信号的FSK调制 ,以满足装定系统数据传输率高、数据传输实时、快速的要求。     

Spatial variation in community structure of a subtropical evergreen broad-leaved forest: Implications for sampling design

With the full survey data for a 24-ha subtropical evergreen broad-leaved forest dynamics plot,we evaluated spatial variation in forest structure characteristics(basal area and aboveground biomass),and calculated the minimal sample size and total sampling area necessary to estimate the forest structure characteristics within 20%(±10%) of the observed values with 95% probability for particular quadrat sizes by using a computer program that is designed to simulate the sampling process by allowing different sized quadrats to be randomly located within the sampling region.We found that(1) based on the 600 20 m×20 m subplots,basal area and aboveground biomass displayed a high degree of variation,with respective coefficients of variation of 27% and 31%;(2) based on the computer simulation analysis,the variability of basal area and aboveground biomass decreased with increasing quadrat size.The number of quadrats required to achieve the specified degree of precision dropped sharply with the increase of quadrat size.However,the total sampling area increased with increasing quadrat size,suggesting that using several small quadrats across the sampling area is more efficient than using fewer larger quadrats.Results of this study are valuable for evaluating the reliability of previous research and may assist researchers in designing effective sampling strategies for future field surveys,particularly in subtropical evergreen broad-leaved forests in China.     

Memway:In-Memory Waylaying Acceleration for Practical Rowhammer Attacks Against Binaries

The Rowhammer bug is a novel micro-architectural security threat, enabling powerful privilege-escalation attacks on various mainstream platforms. It works by actively flipping bits in Dynamic Random Access Memory(DRAM) cells with unprivileged instructions. In order to set up Rowhammer against binaries in the Linux page cache, the Waylaying algorithm has previously been proposed. The Waylaying method stealthily relocates binaries onto exploitable physical addresses without exhausting system memory. However, the proof-of-concept Waylaying algorithm can be easily detected during page cache eviction because of its high disk I/O overhead and long running time. This paper proposes the more advanced Memway algorithm, which improves on Waylaying in terms of both I/O overhead and speed. Running time and disk I/O overhead are reduced by 90% by utilizing Linux tmpfs and inmemory swapping to manage eviction files. Furthermore, by combining Memway with the unprivileged posix fadvise API, the binary relocation step is made 100 times faster. Equipped with our Memway+fadvise relocation scheme,we demonstrate practical Rowhammer attacks that take only 15–200 minutes to covertly relocate a victim binary,and less than 3 seconds to flip the target instruction bit.     

运用服务质量差距模型提升辅导员服务质量的对策

高校辅导员是学生日常思想政治教育及服务育人工作的骨干力量，其工作具有浓重的服务性质。本文运用服务质量差距模型分析辅导员的服务质量差距，发现其服务质量的不足与根源，并提出了弥合服务差距、提升服务质量的对策。     

先秦时期锡矿的找矿方法研究

中国古代文献典籍中,记载了自然界的某些特殊植物、矿物可以成为寻找锡矿的重要标志,经过现代地质调查,发现这些记载与实际情况相吻合.这种简便而行之有效的方法沿用至今,不仅对现代锡矿的勘探具有重要的参考价值,而且也为探讨中国古代锡矿料来源这一重大历史疑案提供了可资借鉴的依据.