谈谈电梯开发质量的要素

开发质量是产品质量的源头。本文通过对电梯开发过程的具体分析，探讨了影响电梯产品开发质量的要素。     

石油生产数据无线实时监测系统

石油生产数据无线实时监测系统是应用于大庆原油生产领域的综合性的大型计算机网络信息系统，具有很好经济效益和社会效益。本文介绍该系统的主要功能、结构和特点。     

图像压缩算法性能的测试与分析工具

本文研究了图像压缩算法性能的评价方法,提出了图像压缩算法性能的测试算法,包括横向比较测试和纵向分解测试,并在此基础上设计并实现了压缩算法性能的测试与分析工具。该工具能够测试和分析压缩算法的性能,并自动生成各种分析图表,为用户提供了方便,具有较大的实用价值。为了提高评价的效率、准确性和全面性,文中提出了测试图像的选择方法和测试结果的分析方法,具有一定的理论意义。     

New method for measuring the degree of conflict among general basic probability assignments

There is doubt about Dempster’s rule of combination because of counter-intuitive results when dealing with conflict information in intelligent reasoning.Therefore,many modified combination rules have been presented in the literature on multi-source information fusion and reasoning with uncertainty.However,the issue of identifying conflict among evidence has been ignored.A new parameter measuring conflict evidence called the conflict distance parameter is defined to determine whether there are conflicts in evidence based on the analysis of existing conflict parameters.At the same time,a decisive rule,which a reasonable conflict measure function should satisfy,is put forward.Finally,an analysis of two typical counter-intuitive situations is given,showing that the new parameter can not only satisfy the decisive rule,but can also attain the same effect as a two-dimensional measure when deciding whether to use the Dempster’s rule of combination,and can exceed its effect when deciding whether to use Dezert-Smarandache theory.     

Attacking contrast enhancement forensics in digital images

Currently, plenty of digital image forensic techniques have been proposed and used as diagnostic tools. It is urgent and significant to assess the reliability of such techniques applied in practical scenarios. In this paper, we investigate the security of existing digital image contrast enhancement （CE） forensic algorithms. From the standpoint of attackers, we propose two types of attacks, CE trace hiding attack and CE trace forging attack, which could invalidate the forensic detector and fabricate two types of forensic errors, respectively. The CE trace hiding attack is implemented by integrating loca] random dithering into the design of pixel value mapping. The CE trace forging attack is proposed by modifying the gray level histogram of a target pixel region to counterfeit peak/gap artifacts. Such trace forging attack is typically applied to create sophisticated composite images which could deceive the prior CE-based composition detectors. Extensive experimental results demonstrate the efficacy of our proposed CE anti-forensic schemes.     

空气压缩机储气罐安全使用条件探讨

为保证空气压缩机储气罐的安全及质量，按照条例和相关标准的要求，从储气罐监管、选材、设计、使用管理、隐患的成因及消除方法等问题进行了探讨，并介绍了储气罐在使用过程中的注意事项。     

数字多用表标准装置的直流电压测量结果不确定度评定

本文介绍了依据JJG-86（直流标准电压源检定规程）用数字多用表标准装置,对多功能校准仪中的直流输出电压进行测量的方法,及测量结果不确定度的评定。     

Improved hydrogen storage performance of the LiNH2–MgH2–LiBH4 system by addition of ZrCo hydride

Significant improvements in the hydrogen absorption/desorption properties of the 2LiNH₂–1.1MgH₂–0.1LiBH₄ composite have been achieved by adding 3wt% ZrCo hydride. The composite can absorb 5.3wt% hydrogen under 7.0 MPa hydrogen pressure in 10 min and desorb 3.75wt% hydrogen under 0.1 MPa H₂ pressure in 60 min at 150 °C, compared with 2.75wt% and 1.67wt% hydrogen under the same hydrogenation/dehydrogenation conditions without the ZrCo hydride addition, respectively. TPD measurements showed that the dehydrogenation temperature of the ZrCo hydride-doped sample was decreased about 10 °C compared to that of the pristine sample. It is concluded that both the homogeneous distribution of ZrCo particles in the matrix observed by SEM and EDS and the destabilized N–H bonds detected by IR spectrum are the main reasons for the improvement of H-cycling kinetics of the 2LiNH₂–1.1MgH₂–0.1LiBH₄ system.