A high capacity steganographic method based on quantization table modification

For the traditional steganographic method of Jsteg,the emmbedment of secret message is completed by dividing cover-image into nonoverlapping blocks of 8×8 pixels,discrete cosine transform(DCT) transforming,and using the standard 8×8 quantization table to quantize.In this paper,a novel steganogra-phic method based on the JPEG quantization table modification is presented.Instead of dividing cover-image into 8×8 blocks,nonoverlapping blocks of 16×16 pixels is used.Both theoretical anlysis and experiment results show that the new methods has larger steganography capacity and better stego-image quality,compared with the method of Jsteg and Chang’s.     

#3机主机抗燃油压降低的原因分析

文章对某电厂#3机存在的主机抗燃油压降低的原因进行了分析,找出主机抗燃油压降低的原因为:在机组打闸状态下,挂闸电磁阀失电,卸荷阀在失去控制油压的情况下打开,而同时电液伺服阀处于开启供油状态,使压力油与回油短路.     

无负压（叠压）供水设备在高层建筑中的应用

由于城市土地资源紧张，房地产的开发向高层发展，还有对供水质量和供水系统可靠性的要求不断提高，再加上目前能源紧缺，利用先进的自动化控制技术以及通讯技术，采用高性能、高节能、高环保，能适应不同领域的无负压（叠压）供水设备成为必然趋势。     

冷热水用聚丙烯管的热熔连接和安装技术

文章介绍了PP管道的性能和应用场所 ,重点介绍了PP管的热熔连接技术和施工安装方法。     

顶岸狭缝间隙对汽油机未燃HC排放的影响研究

通过对汽油机起动及怠速工况下活塞顶岸狭缝处瞬态温度的测量以及对瞬时未燃ＨＣ排放的测量，探索在该工况下未燃ＨＣ排放的主要影响因素以及顶岸狭缝间隙在总体未燃ＨＣ排放中所占的比例，为进一步研究降低火花发动机在起动及怠速工况下未燃ＨＣ的排放提供了依据．文中建立了火花点火发动机起动热机工况下顶岸狭缝间隙处未燃ＨＣ生成的数学模型．与实验结果相比较，证明该模型具有较高的准确性．     

建筑供暖系统的流量调节与节能

文章根据建筑的使用情况，阐述了从供暖的室外系统和室内系统分别进行调节的方法。     

β—型算子矩量的计算

对Bernstein算子,给出任意阶中心矩量的显式表示。     

4HPR对Hela细胞的抑制作用

目的：国外文献报道４ＨＰＲ对乳腺癌具有显著的化学预防及治疗作用。本文拟探讨４ＨＰＲ对Ｈｅｌａ细胞的抑制作用。方法：运用荧光显微镜、电子显微镜、动物致癌试验及流式细胞仪分析等方法。结果：通过荧光显微镜、电子显微镜观察发现Ｈｅｌａ细胞发生明显的形态学改变；流式细胞仪检测，Ｈｅｌａ细胞ＤＮＡ出现显著改变；裸鼠致癌试验也提示４ＨＰＲ抑制Ｈｅｌａ细胞生长。结论：上述结果提示４ＨＰＲ在体内外对Ｈｅｌａ细胞均具有较强的抑制作用。     

The Credit-Risk Decision Mechanism on Fixed Loan Interest Rate with Imperfect Information

In this paper, decision mechanism of credit-risk for banks is studied when the loan interest rate is fixed with asymmetry information in credit market. We give out the designs of rationing and non-rationing on credit risky decision mechanism when collateral value provided by an entrepreneur is not less than the minimum demands of the bank. It shows that under the action of the mechanism, banks could efficiently identify the risk size of the project. Finally, the condition of the project investigation of bank is given over again.     

双箱两肋拱桥单箱合拢吊装技术

结合工程实例，介绍了大跨度双箱两肋拱桥的单箱合拢的吊装技术，包括吊具设计、测量控制、卸载顺序及横向稳定控制等。