基于数字水印的电子印章系统的研究与实现

讨论了法院信息系统中的电子文档安全性问题.针对传统印章的易伪造性弊端,通过将密码签名原理和数字水印技术应用于电子印章之中,并结合COM插件技术实现了机密文档的防篡改功能、身份认证功能及不可否认性功能.     

徐深气田盖层封气有效性研究

利用钻井、地震和分析测试资料,对徐深气田盖层发育及分布、封气能力的有效性和封气时间的有效性进行了研究,得到徐深气田天然气盖层主要为登二段发育的泥岩和营一段顶部发育的火山岩,前者整个断陷分布,是断陷南部营四段火山角砾岩和断陷北部营三段火山岩储集天然气的盖层,后者仅分布在断陷南部,是营一段火山岩储集天然气的盖层。徐深气田中12个气藏盖层排替压力均大于储层排替压力和气藏剩余压力之和,封气能力的有效性好,有利于天然气聚集与保存。登二段和营一段顶部盖层封气性形成时期主要分别为泉一、二段沉积时期和登四段沉积时期,均早于沙河子组煤系源岩的大量排气期（青山口组沉积时期）,封气时间的有效性好,也有利于天然气的大规模富集成藏。     

直流无刷电机驱动的水下电缆绞车系统

水下电缆绞车多采用液压驱动,但液压驱动存在无效动力转换,能源使用率不高,因此直流无刷电机驱动的水下电缆绞车具有实际意义。采用直流无刷电机驱动,不仅提高了水下电缆绞车系统的能源利用率,而且改善了系统的调速性能。与直流有刷电机相比,直流无刷电机可实现充油均压密封,更有利于在水下工作。介绍了直流无刷电机驱动水下电缆绞车的组成、功能及工作原理,针对研制的专用水下直流无刷电机,重点论述了其充油密封原理和工艺,并设计了一种全新的低成本高性能驱动控制电路。该水下电缆绞车系统已初步调试完毕,试验表明各项性能良好,即将投入实际应用。它具有结构简单,工作可靠,成本低的优点,因此在实际工程应用中具有推广意义。     

徐家围子断陷不同储量丰度气藏形成条件的定量研究

为了定量研究徐家围子断陷不同储量丰度气藏形成条件,利用气藏解剖和成藏条件时空匹配关系对该断陷气藏形成的主控因素、形成条件和储量丰度进行了研究,得到源岩供气能力、断裂输导天然气能力和封盖保存能力是气藏形成的3个主控因素。沙河子组源岩供气能力以较好和差为主,断裂输导天然气能力以好为主,封盖保存能力也以好为主。气藏形成条件综合评价以中等气藏为最多,其次是形成条件为好的气藏,差形成条件的气藏最少。气藏以中等储量丰度为主,高和低储量丰度气藏较少;二者之间为正比关系。要形成高储量丰度的气藏,气藏形成条件综合评价应为好等级;要形成中等储量丰度的气藏,气藏形成条件综合评价应为中等等级。     

新型船舶尾轴密封装置设计

本文提出了一种唇口斜置,唇部带双回流的新型船舶尾轴密封环,并介绍了这种环的结构原理、理论分析和设计方法。     

Are metal-induced hypersensitivities in harbor seals associated with liver function?

Environmental exposure to metals is believed to affect marine mammal health adversely including immunosuppression or acute as well as chronic inflammatory processes leading to hypersensitivities or autoimmune diseases. Metal-specific hypersensitivities were found in several pinnipeds of the North Sea. However, hypersensitivity is a complex phenomenon whose characteristics are still not completely understood; in particular, effects on health are not well established. In the present study, we compared basic hematological and biochemical parameters of seals with and without metal-specific hypersensitivities. We found altered hematological parameters and liver enzyme patterns in seals with a metal-induced hypersensitivity, including a reduction in macrophages, an increase in lymphocytes, and elevated levels of lactate dehydrogenase. These findings support the suggestion of a chronic influence of metal pollutants on the health of marine mammals of the North Sea.     

浅析山洞数字形变观测手段的干扰途径及解决方法

本文分析了影响丹东地震台洞室形变仪器观测精度的各种外界干扰因素,提出了解决干扰的措施办法,希望能为同行提供参考。     

降低宝石加工过程中脱杆率的研究

脱杆现象常常会中断宝石的加工过程,是影响中国宝石加工企业生产效率与产品质量的主要因素之一。通过分析火漆胶粘结宝石的原理与脱杆原因后认为,在宝石的加工过程中,改善工艺操作及相应的工艺材料、规范操作要领可有效地降低宝石的脱杆率,对宝石的加工与生产有一定的现实指导意义。     

Contaminants still high in top-level carnivores in the Southern California Bight: levels of DDT and PCBs in resident and transient pinnipeds

Highly industrialized areas, such as the Southern California Bight, often have high levels of contaminants in marine sediments, which can cause chronic exposure to organisms long after their use has ceased. tDDT and tPCB were analyzed in the blubber of 145 stranded pinnipeds that died at local marine mammal centers between 1994 and 2006. Resident species (California sea lion and Pacific harbor seal) had significantly higher concentrations of tDDT and tPCB than the transient species (northern elephant seal). Adult female California sea lions had significantly lower concentrations of tDDT and tPCB than pups, yearlings, and adult males. Concentrations of both tDDT and tPCB in California sea lions significantly declined over time, but did not change in northern elephant seals. Current concentrations of tDDT and tPCB in California sea lions and harbor seals are among the highest values reported worldwide for marine mammals and exceed those reported to cause adverse health effects.