基于随机粗糙样本的统计学习理论研究

介绍随机粗糙理论的基本内容。提出随机粗糙经验风险泛函,随机粗糙期望风险泛函,随机粗糙经验风险最小化原则等概念。最后证明基于随机粗糙样本的统计学习理论的关键定理并讨论学习过程一致收敛速度的界。     

High Speed Quantum Key Distribution Over Optical Fiber Network System

The National Institute of Standards and Technology (NIST) has developed a number of complete fiber-based high-speed quantum key distribution (QKD) systems that includes an 850 nm QKD system for a local area network (LAN), a 1310 nm QKD system for a metropolitan area network (MAN), and a 3-node quantum network controlled by a network manager. This paper discusses the key techniques used to implement these systems, which include polarization recovery, noise reduction, frequency up-conversion detection based on a periodically polled lithium nitrate (PPLN) waveguide, custom high-speed data handling boards and quantum network management. Using our quantum network, a QKD secured video surveillance application has been demonstrated. Our intention is to show the feasibility and sophistication of QKD systems based on current technology.     

Decline in respiratory symptoms in service workers five months after a public smoking ban

Objective

To evaluate the effect of a total ban on smoking indoors in restaurants and other hospitality business premises in Norway, on respiratory symptoms among workers in the industry.

Methods

Phone interviews with 1525 employees in the hospitality business were conducted immediately before the enacting of the law. In a follow‐up study five months later, 906 of the workers from the baseline sample participated. Questions were asked on demographic variables, passive smoking exposure, personal smoking, attitudes towards the law, and five respiratory symptoms. Change in symptom prevalence was analysed with McNemar''s test and with analysis of variance (ANOVA) for repeated measures.

Results

The prevalence of all five symptoms declined after the ban; for morning cough from 20.6% to 16.2% (p < 0.01); for daytime cough from 23.2% to 20.9%; for phlegm cough from 15.3% to 11.8% (p < 0.05); for dyspnoea from 19.2% to 13.0% (p < 0.01); and for wheezing from 9.0% to 7.8%. ANOVA showed that the largest decline in symptom prevalence was seen among workers who themselves gave up smoking, and subjects with a positive attitude towards the law before it took effect.

Conclusion

A significant decrease in respiratory symptoms among service industry workers was found five months after the enacting of a public smoking ban.     

城市特征新论

城市本身是一个辩证的对立统一体,以往对城市系统单个特征的认识或强调是片面的,需要从对立统一规律的角度来重新审视城市特征.笔者认为,城市的特征主要有:集聚与扩散作用的共存性及交替主导性、溢出效应与乘数效应的互动性、公共性与经营性的兼容性、多样化与两极分化的并存性、线性关系向非线性关系的递进性等.     

核燃料循环设施安全关键岗位识别方法初探

研究建立了基于岗位的工作责任、安全风险和专业技能等特性指标的核燃料循环设施安全关键岗位识别方法,给出了核燃料循环设施安全关键岗位的定义、识别指标体系、识别原则、识别评价流程和后处理设施应用案例。     

Impact of coarse-grained measurement with finite range on continuous-variable quantum key distribution

In continuous-variable quantum key distribution, detectors are necessarily coarse grained and of finite range. We analyze the impact of both features and demonstrate that while coarse graining adds a fixed error to the estimated excess noise, finite range degrades the estimation accuracy of both transmission and excess noise. Moreover, the inaccurate estimation due to finite range may results in secret key rate underestimation, even misjudgment of security. To compensate these consequences, tuning the modulation variance is a possible way.     

An Improved Identity-Based Ring Signcryption Scheme

Abstract

Biometrics can be defined as science by which an individual is identified through analyses of physical data and behavioral characteristics.¹ The measurement of an individual's characteristics quantifies his or her physical, behavioral characteristics. The physically unique characteristics include, but are not limited to, fingerprints, hand or palm geometry, retina or iris scans, voice or facial characteristics, keystroke patterns, and gait. These presumably unique characteristics are used, in turn, to recognize (identify), authenticate, deny, or grant access based on the individual's characteristics.     

The Modified Signature Scheme Based on Factoring and Discrete Logarithms

ABSTRACT

Laih and Kuo developed two highly secure and efficient signature schemes based on factoring and discrete logarithms. Unfortunately, their schemes require many keys for signing document and verifying signature. Li, Tzeng, and Hwang improved one of their schemes and managed to reduce the number of keys, but unfortunately the improved scheme was shown to be insecure by Qian, Chao, and Bao. In this paper, a new modified scheme of Li-Tzeng-Hwang is presented with two main results: The modified scheme requires fewer keys than the scheme by Laih and Kuo, and it is able to withstand many attacks including the one mentioned by Qian, Chao and Bao.     

Modified Lim-Lee Combing Using Signed Window and Direct Doublings

ABSTRACT

The fast exponentiation is a crucial one in any kind of public key cryptosystem. Lim-Lee proposed a method for an efficient exponentiation in elliptic curve by dividing n-bit scalar into equal length of simple scalars. In this paper, the general Lim-Lee method is further improved by using the signed binary window method and direct doublings.     

600MW机组布袋除尘器综合集成施工技术

阐述了600 MW机组布袋除尘器施工的关键技术,施工过程中把设备部件最大化地面组合后,分单元退吊、配合自制吊具解决了现场吊车站位及起重能力不够的难题,花板梁水平度控制、壳体正压密封试验、花板荧光粉检漏等综合集成技术,保证了整个工程安全、优质、高效地完成,从而提高了布袋除尘器的除尘效率,取得良好的经济效益。