一种新型基于环上带误差学习问题的认证密钥交换方案

利用格上判定带误差学习问题(Ring-DLWE)困难假设,该文基于Peikert的调和技术构造认证密钥交换方案。在标准模型下,该方案是CK模型中可证明安全的,并达到弱前向安全性(wPFS)。与现有的基于LWE的密钥交换方案相比,该方案使用平衡的密钥提取函数,因而保护共享会话密钥,同时因其基于格中困难问题,所以能抵抗量子攻击。     

Morphology and magnetic properties of Sm2Co7/α-Fe nanocomposite magnets produced by high energy ball milling and spark plasma sintering

In this article,the Sm₂Co₇/α-Fe nanocomposite magnets were prepared by high energy ball milling and spark plasma sintering method.The effect of soft phase content on the magnetic properties was studied.Up to 30 wt% α-Fe was added into Sm₂Co₇ matrix without the decrease of remanence.Optimal energy product(BH)max of 9.2 MGOe was obtained with 20 wt% α-Fe.TEM observation shows that the grain size of α-Fe is 20-50 nm which ensures a good coupling effect between soft and hard phase.One more thing needs to be mentioned is that there exists inter-diffusion between Sm-Co phase and α-Fe phase.Moreover,our results can also illustrate that the Sm₂Co₇/α-Fe nanocomposite magnets are able to acquire better magnetic properties than the SmCo₅/α-Fe magnets prepared by the same process due to the large domain width of Sm₂Co₇ phase.     

尺寸链在机器装配中的应用

着重分析应用尺寸链的原理,达到装配精度的方法,合理解决机器质量的保证问题。     

Theory of Sample Surveys

Orthogonal arrays are used widely in manufacturing and high-technology industries for quality and productivity improvement experiments. For reasons of run size economy or flexibility, nearly-orthogonal arrays are also used. The construction of orthogonal or nearly-orthogonal arrays can be quite challenging. Most existing methods are complex and produce limited types of arrays. This article describes a simple and effective algorithm for constructing mixed-level orthogonal and nearly-orthogonal arrays that can construct a variety of small-run designs with good statistical properties efficiently.     

Castles and Pavilions: Creating New Hybrid Places of Exchange

Tom Holbrook , Director at architecture and urban design practice 5th Studio, describes two projects in the south of England that respond spatially to the needs of ‘the knowledge economy’. The first is the River Lea Park, to the east of London, which promotes open connectivity between people in a post- industrial landscape; and the second is the Creative Exchange in St Neots, Cambridgeshire, a building designed to accommodate local enterprise. Both are designed to redirect social and economic activities, supporting creative swarming, and establishing what Stafford Beer has coined as ‘platforms for change’.     

Thermo‐mechanical Coupling Properties of Proton Exchange Membrane in Liquid Water

In this study, the effects of the combination and interaction of thermal and mechanical loading on mechanical behaviors of proton exchange membranes (PEMs) under immersed condition were investigated. Experiments under two kinds of loading path were performed: the quasi‐simultaneous loading path where mechanical loads and temperature occurred simultaneously and the rectangular loading path where thermal and mechanical loads were inserted in turn. The quasi‐simultaneous loading path is composed of in‐phase, 90° and 180° out‐of‐phase loading paths. Comparison between in‐phase and 180° out‐of‐phase loading paths showed that strain accumulation under in‐phase loading path mainly resulted from creep strain while that under 180° out‐of‐phase loading path were mostly induced by cyclic stress. Accumulation of strain was comprised of tensile strain and creep strain, and these two strain components showed different evolution trends with thermo‐mechanical cycles. In addition, the modulus of the membrane was history‐dependent as indicated from results of rectangular loading path. Through comparing creep strain with strain energy density which is an indicator of damage in the membrane, we came to the conclusion that creep strain contributed to the damage of the membrane in the first three cycles.     

放射性核素在地表水体中之沉积模式

放射性核系在岸边、滩涂带的沉积,将会对有关公众构成内、外照射,这是滨海核电站环境影响评价中不可回避的、重要的照射途径。本文改进了Ｕ．Ｓ．ＮＲＣ提出的简单的沉积模式,用量纲分析法推导出了核素从水相向沉积相的转移速度Ｋｃ的解析表达式,之后论述了在实验室内用模拟垂直湍流交换系数Ｋｚ的谐振装置估测Ｋｃ（Ｋｚ）的方法,最后提出了用于实际厂址环境影响评价中相关参数值的获取方法。     

Spin reorientation,normal and inverse magnetocaloric effects in heavy rare-earth iron garnets

Experiments for heavy rare-earth iron garnets Ho₃Fe₅O₁₂ and Er₃Fe₅O₁₂ show a compensation effect characterized by a near zero magnetization at 134 K and 80 K, respectively. The magnetic entropy change calculated according to the Maxwell's relation is shown to be positive and negative, indicating both normal and inverse magnetocaloric effects exist in the sample. The critical temperature (134 K for Ho₃Fe₅O₁₂, 80 K for Er₃Fe₅O₁₂) of the two types of magnetocaloric effect occurs at almost the same temperature as the compensation point. However, the compensation effect is attributed to the multiple exchange interactions among the octahedral sites Fe³⁺, the tetrahedral sites Fe³⁺ and the dodecahedral sites R³⁺, while the reversal of the magnetocaloric effect is originated from the spin reorientation. The maximum magnetic entropy change of the normal magnetocaloric effect is 4.72 J kg⁻¹ K⁻¹ for Ho₃Fe₅O₁₂ at 34 K and 4.94 J kg⁻¹ K⁻¹ for Er₃Fe₅O₁₂ at 24 K, respectively. Moreover, all the positive slopes of basic Arrott plots suggest only the second-order phase transition existing in Ho₃Fe₅O₁₂ and Er₃Fe₅O₁₂.     

由骨胶水解液中分离提取L-羟脯氨酸和L-脯氨酸的实验研究

本文报道了由骨胶水解液中分离提取 L -羟脯氨酸和 L-脯氨酸的工艺。产品产率为 L-Hy P5.2 8% ;L-Pro3 .6 %。工业化产品经按日本有关标准检测全部合格。该工艺已通过内蒙古自治区经委的验收     

废热锅炉事故分析及处理

叙述了废热锅炉的损坏情况及检查结果,定性分析了废热锅炉事故机理,介绍了薄管板废热锅炉裂管的处理方案、耐火浇注料的选取及废锅壳程的清洗方案。