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1.
In the study, lamb, feed and soil samples were collected from three regions of China in the year 2017 and 2018. The δ13C and δ15N values in lamb (defatted dry mass and lipids) and grass and the contents of nine elements in lamb, grass and soil were determined. The results indicated that except for Fe, Zn and Rb, most variables of lamb showed significant differences among two or three regions, and the contents of Fe, Sr and Cs showed significant differences between two years, and the contents of Cu and Zn showed significant differences among different muscle sections. Besides, significant correlations were found for δ13C between defatted lamb and lipid (r2 = 0.973, P < 0.05) and for the element contents between lamb and soil. Finally, four key variables δ13C, δ15N, Sr and Mo were selected through stepwise canonical discriminant analysis with the cross-validation correct classification rate of 99.1%.  相似文献   
2.
Recently, the Tactile Internet (TI) becomes a new era of the Internet. The TI provides ultra-reliable, ultra-responsive and intelligent network connectivity for delivering real-time control and physical haptic experiences from a remote location. The TI provides a different feeling to human–machine interaction by implementing the real-time interactive systems. In this review article, we discuss a generalized authentication model which can be used to perform authentication procedure among different communicating parties in order to secure remote surgery in the TI environment. By using the proposed authentication model, an authentication protocol can be designed so that an authenticated surgeon can use the robot/robotic arms to perform the surgery securely as well as remotely. Since the application is very critical, the important instructions provided by the surgeon to the robot/robotic arms must not be leaked in between the communication during the surgical procedure. To deal with this emerging research area, a secure mutual user authentication mechanism should be provided between a remote surgeon and the robot/robotic arms so that they can communicate securely using the established session key among them. Further, several security issues and challenges for such kind of communication are also discussed in this article. Finally, we discuss few points that need to be considered as future research works that are related to authentication for securing remote surgery in the TI environment.  相似文献   
3.
Dielectric property at high microwave frequency region has been utilized for possible rapid detection and screening of different types of meat, especially for halal authentication. This investigation focused on both raw and sterilized (processed) beef, pork, and chicken samples. Dielectric response that consists of dielectric constant and dielectric loss factor was measured over the range of 0.5 to 50 GHz. All raw and sterilized meat samples could be differentiated by the dielectric values. Two distinct peaks were observed only for both raw and sterilized pork samples at the frequency around 7.43 and 31.19 GHz. These peaks can potentially be linked to compounds that exist only in pork such as DNA, microbes, enzyme, proteins, amino acids, and many others. Dielectric values for sterilized samples were lower than raw samples due to molecule structural changes that occurred in the samples. The dielectric results promise a great potential of utilizing dielectric properties as a rapid on-site detection approach prior to subsequent laborious analysis.  相似文献   
4.
Neat Scottish whiskies and the local source water used for and during whisky production have been analysed for their 2H and 18O isotopic composition by High Temperature Conversion–Isotope Ratio Mass Spectrometry (TC/EA–IRMS). With coefficients of determination R2 for δ2H and δ18O of 0.71 and 0.88, respectively, measured δ2H and δ18O values for water used in the production of Scottish whisky were found to be well correlated with the δ2H and δ18O values observed for the corresponding whiskies. By plotting bulk 2H against bulk 18O isotope abundance data of authentic whisky and counterfeit whisky samples it was possible to discriminate between samples of authentic whisky and samples of counterfeit whisky.  相似文献   
5.
随着电子商务魅力的日渐显露,虚拟企业、虚拟银行、网络营销等一大批前所未闻的新词汇正在为人们所熟悉和认同。但同时也有众多问题需要解决.电子商务中的安全要素及安全技术也日益显得重要,因为它直接关系着用户的各种利益。着重描述了电子商务中的安全隐患和几点关键的安全保障技术。  相似文献   
6.
The TaqMan real-time PCR has the highest potential for automation, therefore representing the currently most suitable method for screening, allowing the detection of fraudulent or unintentional mislabeling of species. This work describes the development of a real-time polymerase chain reaction (RT-PCR) system for the detection and identification of common octopus (Octopus vulgaris) and main substitute species (Eledone cirrhosa and Dosidicus gigas). This technique is notable for the combination of simplicity, speed, sensitivity and specificity in an homogeneous assay.  相似文献   
7.
The potential of low field NMR (LF NMR) as a fast monitoring technique to estimate the quality of hake (Merluccius merluccius) frozen stored at -10°C for up to 6months was evaluated. LF NMR clearly detected three populations of water: water strongly bound to macromolecules (T(2b)), trapped water (T(21)) and free water (T(22)). As storage time increased, and concomitant with an increase in the T(22) and a decrease in the T(21) water populations, the water holding capacity (WHC) and apparent viscosity values decreased and the shear strength increased, reflecting the characteristic loss of juiciness and tougher texture developed by hake during frozen storage. Two mathematical models were constructed: a simple regression using the biexponential analysis of the relaxation times (T(21), T(22)) and amplitudes (A(21), A(22)) and a partial least square regression (PLS) of CONTIN analysis. Both models seemed suitable to estimate the quality of the product.  相似文献   
8.
以大型销售MIS的数据安全问题为例,提出以终端ID号、钥匙盘ID号和终端用户样本指纹绑定为一体的身份认证方案。该方案采用软硬件协同工作方式,克服了传统身份认证模式或安全性能低,或运算成本高等缺陷,提高了认证效率,并保证了合法用户操作的唯一性和认证过程的不可抵赖性。提出的基于ECC与一维混沌加密算法优点相结合的混合加密方案,使基于互联网传送的数据安全性有了实质性提高。基于分治叠加法的大整数计算成果运用,克服了计算机精度域的限制,使密钥空间从理论上趋向于无穷大。试验结果表明,基于混合加密算法的数据安全方案具有良好的抗穷举攻击和抗差分攻击能力。该项研究为解决各类MIS的数据安全问题提供了重要策略,意义重大。  相似文献   
9.
PKI技术及其在校园网中的应用研究   总被引:1,自引:0,他引:1  
将PKI技术引入校园网络,构建基于PKI技术的数字认证中心,既保证了校园网络的安全性,实现安全文件传输,又解决了校园网络用户身份认证的问题,推进高校信息化的同时提高校园网的安全性。  相似文献   
10.
骆嘉伟  唐国英 《计算机应用》2012,32(6):1782-1786
针对区域卫生信息化平台中的多个应用系统的统一认证授权和单一登录,以及基于角色的访问控制模型不能直接应用到单点登录中等问题,提出了一种基于角色组的角色控制策略和JASIG-CAS相结合的统一身份认证系统。中央认证服务(CAS)服务端引用MyBatis技术有效展示了子系统信息,各个应用系统之间采用Axis2来实现用户信息同步,并利用Session存储用户在各个系统中的权限来减少对数据库的频繁访问,从而显著改善了平台的性能。该单点登录系统实现了统一用户管理、统一权限分配、统一平台风格样式等功能。最后,采用专业压力测试工具LoadRunner8.0对平台进行了性能测试和分析,测试结果表明该系统总体性能稳定,平台设计合理。  相似文献   
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