平衡辐射统计理论的探讨

运用经典统计物理理论对平衡辐射进行研究,存在着致命的缺陷,主要原因是经典统计物理理论把平衡辐射场看作是由无穷多个单色平面波的叠加,按能量均分定理,每个单色平面波具有一定的能量值,因而平衡辐射场的总能量将趋于无穷大。要正确解决经典统计物理对平衡辐射的缺陷,需要用量子统计物理理论来研究。量子统计理论认为,平衡辐射是由大量光子组成,光子的自旋量子数为1,满足玻色分布,从而能得到与实际完全相符的结论,即普朗克公式。利用普朗克公式还可以得出瑞利-金斯公式以及维恩公式等其他一些重要结论。     

重大事件对城市发展影响研究综述

重大事件对城市在促进当地社会经济发展,提高举办城市的知名度方面具有重要影响。具体地体现在以下八个层面：城市整体发展、城市空间、城市规划和建筑设计、城市经济社会发展、城市生活、城市公共管理、提升城市形象与城市国际化。     

带可变核的分数次积分交换子的有界性

研究由带变量核的分数次积分算子TΩ,α和Lipβ（Rn）（0〈β≤1）函数生成的交换子[b,TΩ,α],证明了当核函数Ω∈L∞×Lr（Sn-1）（r≥1）时,[b,TΩ,α]从Herz型Hardy空间H.Kηq,p1（Rn）到Herz型空间Kηq,p2（Rn）的有界性.     

Optimization and Finite Element Analysis of the Temperature Field in a Nitride MOCVD Reactor by Induction Heating

A susceptor structure with a ring channel for a vertical metalorganic chemical vapor deposition reactor by induction heating is proposed. Thus the directions of heat conduction are changed by the channel, and the channel makes the heat in the susceptor redistribute. The pattern of heat transfer in this susceptor is also analyzed. In addition, the location and size of the channel in the susceptor are optimized using the finite element method. A comparison between the optimized and the conventional susceptor shows that the optimized susceptor not only enhances the heating efficiency but also the uniformity of temperature distribution in the wafer, which contributes to improving the quality of the film growth.     

基于网络搜索数据的区域旅游指数及其微观动态:以西安为例

地理位置与交通条件是旅游的重要先决条件,然而高峰期突然蜂拥而至的客流往往令身陷其中的游客多有抱怨和排斥,景区管理部门亦力有不逮,因此,如何及时预警、调度和配置有限的旅游资源便成为大众和旅游管理部门的热点话题.最直接的方法是客流量预测,然而目前的客流量统计主要来源于对旅行社、景区及其周边酒店等机构部门的事后统计和推断,这类数据需要层层汇总上报审批,发布相对滞后,并且常以月度或季度为频率.网络搜索数据记录了游客成行之前的需求与偏好,数据本身是前置的、实时的,而且是直接对游客行为痕迹的记录,数据质量也不依赖于被调查一方的动机和配合程度.以古丝绸之路的起点西安为例,基于用户的旅游信息搜索行为,通过设置初始关键词和拓展关键词筛选相关搜索词构造区域旅游指数,采用HEGY季节协整检验和基于X12季节调整的混合模型均发现,区域旅游指数并不具有显著的前兆效应,只是与实际旅游客流量存在同期关联,可以进行实时预测.进一步,在Prophet预测模型中引入节假日效应,显著地降低了拟合与预测误差.     

The supply voltage scaled dependency of the recovery of single event upset in advanced complementary metal-oxide-semiconductor static random-access memory cells

Using computer-aided design three-dimensional simulation technology,the supply voltage scaled dependency of the recovery of single event upset and charge collection in static random-access memory cells are investigated.It reveals that the recovery linear energy transfer threshold decreases with the supply voltage reducing,which is quite attractive for dynamic voltage scaling and subthreshold circuit radiation-hardened design.Additionally,the effect of supply voltage on charge collection is also investigated.It is concluded that the supply voltage mainly affects the bipolar gain of the parasitical bipolar junction transistor(BJT) and the existence of the source plays an important role in supply voltage variation.     

韶关冶炼厂:积极参赛增添企业创新发展新动力

韶关冶炼厂创建于1966年,是我国首家采用在系统编程(ISP)专利技术的大型铅锌冶炼企业,主要生产铅锭、锌锭、锌系列合金、银锭、粗铜等产品.公司连续多年被评为国家一级企业,荣获国家科技进步奖二等奖等多个奖项.当前,韶关冶炼厂正在进行升级改造,建立了稀贵金属绿色回收与提取实验室和半导体材料实验室等研发平台,以含锗铟原料为...     

Generation of GHZ States via Deterministic Entanglement Concentration

We present the generation of six-particle Greenberger Horne-Zeilinger （GHZ） states via deterministic entanglement concentration and generalize the scheme to the case of 2N particles. We show that arbitrary 2N-particle GHZ states can be obtained with certain probability via entanglement concentration. This may provide a new perspective for the preparation of multi-particle GHZ states. This study is also an exploration on the theory of deterministic entanglement concentration.     

退火温度对430不锈钢冷轧板组织和力学性能的影响

针对现场生产的430不锈钢冷轧板,通过高温连续退火实验研究了退火温度对材料显微组织、强度、塑性以及各向异性性能的影响.通过实验得到了合理的两段式加热连续退火工艺:选取中间温度为600℃,加热II段的加热速率为2.3℃·s-1,最高加热温度为840℃.随着退火温度的升高,薄板的屈服强度和硬度呈明显的两阶段降低趋势,延伸率呈"S"型趋势增加,平均塑性应变比基本保持不变(1.25左右),而轧制平面各向异性指数有一定的降低.针对430不锈钢冷轧板分别建立了屈服强度与退火软化率和延伸率之间的定量关系.