Accelerating BPC-PaCo through Visually Lossless Techniques

Fast image codecs are a current need in applications that deal with large amounts of images. Graphics Processing Units (GPUs) are suitable processors to speed up most kinds of algorithms, especially when they allow fine-grain parallelism. Bitplane Coding with Parallel Coefficient processing (BPC-PaCo) is a recently proposed algorithm for the core stage of wavelet-based image codecs tailored for the highly parallel architectures of GPUs. This algorithm provides complexity scalability to allow faster execution at the expense of coding efficiency. Its main drawback is that the speedup and loss in image quality is controlled only roughly, resulting in visible distortion at low and medium rates. This paper addresses this issue by integrating techniques of visually lossless coding into BPC-PaCo. The resulting method minimizes the visual distortion introduced in the compressed file, obtaining higher-quality images to a human observer. Experimental results also indicate 12% speedups with respect to BPC-PaCo.     

高强度大桥缆索用盘条生产现状分析

最近5年，大桥缆索用镀锌钢丝抗拉强度有了大幅提高，从1 770 MPa级、1 860 MPa级、1 960 MPa级到目前的2 000 MPa及以上级别，扭转指标有了颠覆性的改变，从之前的几转到目前的十几转、二十几转。论述了国内外钢铁企业生产大桥缆索镀锌钢丝用盘条的不同现状。从成分设计、生产工艺流程、盘条韧化处理方式和组织特点等方面进行阐述，讨论了国内外不同生产工艺特点及发展趋势，为中国大桥缆索镀锌钢丝用盘条的生产提供理论支持。     

CGCS2000与WGS84之间转换的研究

坐标系统是在海洋石油勘探过程中基础的技术支撑,对采集的数据与现有数据的匹配、处理及融合等都会产生影响。本文对CGCS2000的基础参数和特点进行介绍,将WGS84与CGCS2000进行对比,根据现有的转换模型,对两者之间的转换参数进行研究。     

Landscape dynamics of Mediterranean montane grasslands over 60 years and implications for habitats conservation. A case study in the northern Apennines (Italy)

Widespread trends of abandonment have strongly affected Mediterranean mountains after the Second World War, triggering spontaneous recolonisation of forests. A diachronic analysis of the landscape in a Natura 2000 site (Tuscany, Italy) was carried out using digital aerial photographs (1954, 2013) and a GIS-based methodology, focusing on territories above 1300 m a.s.l. The detected variations of total areas, patch shape, patch dimensions and selected metrics showed a notable shift of the vegetation towards woody types and a drastic reduction of open grasslands, some with high conservation value, accompanied by a strong increase in patch number, surface and edge. A decrease of SDI and SEI diversity indices was also observed. Considering that fragmentation is one of the main causes threatening habitats and species, our results point out a clear necessity for a monitoring programme and suitable actions aimed at improving the status of biodiversity-rich montane grasslands.     

JPEG encryption for image rescaling in the encrypted domain

This work proposes a novel protocol of encrypting the JPEG image suitable for image rescaling in the encrypted domain. To protect the privacy of original content, the image owner perturbs the texture and randomizes the structure of the JPEG image by enciphering the quantized Discrete Cosine Transform (DCT) coefficients. After receiving the encrypted JPEG image, the service provider generates a rescaled JPEG image by down-sampling the encrypted DCT coefficients. On the recipient side, the encrypted JPEG image rescaled by the service provider can be decrypted to a plaintext image with a lower resolution with the aid of encryption keys. Experimental results show that the proposed method has a good capability of rescaling the privacy-protected JPEG file.     

6kV厂用电源快切装置误动原因分析及处理

厂用电源的快速切换技术近年来在大型发电机组厂用电系统中运用日臻完善和成熟,显示出它对确保机组稳定运行的优越性,并已在生产实际中积累了丰富的运行经验。分析了平顶山某电厂应用的2种快速切换装置的原理和使用中出现的问题及解决方法,提出了解决的思路。     

5ESS-2000型电话交换机计费磁带的制作

介绍了5ESS-2000型电话交换机的计费方式、计费磁带的制作方法及其相关注意事项。     

EPS2000和AutoCAD平台下图形文件的无缝转换

探讨了通过EPS2000的模块设置将图形件转换成AutoCAD平台下的图形件的方法，并应用适当的方法和程序处理来实现测图系统问图形件的无缝转换，达到资源合理共享的目的。     

HND供电自动化系统在工厂中的应用

变电站自动化系统从集中式到分布式,其技术特点及运行要求等方面取得了极大的进展.建设ND2000供电自动化系统,可以实现工厂生产自动化、企业信息化,为实现工程高产高效目标奠定基础.     

5ESS-2000型程控交换机的计费原理及应用

介绍了5ESS-2000型程控交换机计费的基本原理及其应用。