Secure Two-Party Distance Computation Protocol Based on Privacy Homomorphism and Scalar Product in Wireless Sensor Networks

Numerous privacy-preserving issues have emerged along with the fast development of the Internet of Things. In addressing privacy protection problems in Wireless Sensor Networks(WSN), secure multi-party computation is considered vital, where obtaining the Euclidian distance between two nodes with no disclosure of either side’s secrets has become the focus of location-privacy-related applications. This paper proposes a novel Privacy-Preserving Scalar Product Protocol(PPSPP) for wireless sensor networks. Based on PPSPP, we then propose a Homomorphic-Encryption-based Euclidean Distance Protocol(HEEDP) without third parties. This protocol can achieve secure distance computation between two sensor nodes. Correctness proofs of PPSPP and HEEDP are provided, followed by security validation and analysis. Performance evaluations via comparisons among similar protocols demonstrate that HEEDP is superior; it is most efficient in terms of both communication and computation on a wide range of data types, especially in wireless sensor networks.     

Effect of Graphene Nanoplatelets addition on mechanical properties of pure aluminum using a semi-powder method

In recent years, graphene has attracted considerable research interest in all fields of science due to its unique properties. Its excellent mechanical properties lead it to be used in nano-composites for strength enhancement. This paper reports an Aluminum–Graphene Nanoplatelets(Al/GNPs)composite using a semi-powder method followed by hot extrusion. The effect of GNP nano-particle integration on tensile, compressive and hardness response of Al is investigated in this paper. It is demonstrated that 0.3 wt% Graphene Nanoplatelets distributed homogeneously in the matrix aluminum act as an effective reinforcing filler to prevent deformation. Compared to monolithic aluminum(in tension), Al–0.3 wt% GNPs composite exhibited higher 0.2% yield strength(+14.7%), ultimate tensile strength(+11.1%) and lower failure strain( -40.6%). Surprisingly, compared to monolithic Al(in compression), Al–0.3 wt% GNPs composite exhibited same 0.2% compressive yield strength and lower ultimate compression strength(- 7.8%),and lower failure strain(- 20.2%). The Al–0.3 wt% GNPs composite exhibited higher Vickers hardness compared to monolithic aluminum(+11.8%).Scanning electron microscopy(SEM), Energy-Dispersive X-ray Spectroscopy(EDS) and X-ray diffraction(XRD) were used to investigate the surface morphology, elemental percentage composition, and phase analysis, respectively.     

GLP-1R agonists therapy for type 2 diabetes

Glucagon-like peptide-1 receptor （GLP-1R） agonists are widely used for treating type 2 diabetes mellitus （T2DM） be- cause of their glucose-lowering and weight-losing effects, and low risk of hypoglycemia. Hence, there is considerable interest in understanding the mechanism underlying the beneficial effects of GLP-I and developing stable and effective GLP-1R agonists. Here, we summarize the presently known mechanism of GLP-I actions, which are mainly through regulating cAMP-PKA signaling pathway; the latest developments in novel clinical GLP-1R agonists are also introduced, which are characterized with multiple properties, such as extended half-life, reduced side-effects, lower production costs and more convenient drug dosing mode. The potential risk of GLP-I-based therapeutics, an often-ignored fact, is also discussed.     

科学饮食 营造健康生活

饮食是人类生存的根本,是生命的源泉。伴随着人民生活水平的提高和对餐饮业需求的增长,饮食健康成了一道靓丽的风景。饮食文化、合理膳食、科学烹调和饮食习惯引起了人们广泛关注。     

地方高校“播音与主持艺术专业热”透视

新世纪以来,伴随着“艺考”的升温,中国高等教育出现了前所未有的“播音与主持艺术专业热”.具体表现在开设高校增多、报考学生数量庞大、专业规模迅速膨胀和专业培训红火等方面.专业门槛相对较低、专业收费相对较高、传媒业的迅猛发展、播音与主持人的明星效应等是导致“播音与主持艺术专业热”的主要原因.只有政府、学校、家长、学生共同面对,才能使“播音与主持艺术专业热”降温,从而回归正常轨道.     

地板上尿渍足迹的溴酚蓝溶液新型增强技术研究

目的探索一种新型地板表面尿渍足迹的溴酚蓝酒精溶液增强技术。方法使用BRWY-1雾化器对75%酒精溴酚蓝酒精溶液对地板表面上不同遗留时间和遗留量的尿渍足迹进行溴酚蓝增强处理。结果使用BRWY-1雾化器对75%酒精溴酚蓝溶液雾化喷涂,能够有效增强地板表面上的尿渍足迹,时间约为30 s,尿渍足迹纹线颜色为蓝色,特征清晰连贯、与地板反差明显。结论 BRWY-1雾化器雾化75%酒精溴酚蓝溶液能够有效增强地板表面与尿渍足迹的反差,可作为一种新型尿渍足迹显现和增强技术,有效提高该类痕迹的发现率、提取率和利用率。     

GPSNISNAV integrated relative navigation and attitude determination system for ultra-close spacecraft formation flying

For the improvement of accuracy and better fault-tolerant performance, a global position system (GPS)/vision navigation (VISNAV) integrated relative navigation and attitude determination approach is presented for ultra-close spacecraft formation flying. Onboard GPS and VISNAV system are adopted and a federal Kalman filter architecture is used for the total navigation system design. Simulation results indicate that the integrated system can provide a total improvement of relative navigation and attitude estimation performance in accuracy and fault-tolerance.     

Effects of AlN on the densification and mechanical properties of pressureless-sintered SiC ceramics

In the present work, Si C ceramics was fabricated with Al N using B_4 C and C as sintering aids by a solid-state pressureless-sintered method. The effects of Al N contents on the densification, mechanical properties, phase compositions, and microstructure evolutions of as-obtained Si C ceramics were thoroughly investigated. Al N was found to promote further densification of the Si C ceramics due to its evaporation over 1800 °C,transportation, and solidification in the pores resulted from Si C grain coarsening. The highest relative density of 99.65% was achieved for Si C sample with 15.0 wt% Al N by the pressureless-sintered method at 2130 °C for 1 h in Ar atmosphere. Furthermore, the fracture mechanism for Si C ceramics containing Al N tended to transfer from single transgranular fracture mode to both transgranular fracture and intergranular fracture modes when the sample with 30.0 wt% Al N sintered at 1900 °C for 1 h in Ar. Also, Si C ceramics with 30.0 wt% Al N exhibited the highest fracture toughness of 5.23 MPa m~(1/2) when sintered at 1900 °C.     

Enhanced mechanical properties of AZ31 magnesium alloy sheets by continuous bending process after V-bending

The effects of V-bending process, continuous bending process and combination process on the microstructure and mechanical properties and formability of an AZ31 magnesium alloy sheet were investigated. The experimental results showed that no twins were found in the microstructure of all samples after processes due to the fine grain. The V-bending and continuous bending processes were proved to be an effective approach to modify the mechanical properties and formability. While the samples after the combination process exhibited better mechanical properties and formability than the single processed sample. The yield strength significantly decreased with the value of 100 MPa and the fracture elongation enhanced to 18.3% at room temperature. The Erichsen value was 5.0 mm which was significantly increased by 117% compared with as-received sample. The superior formability of combination processed samples was mainly attributed to the smaller r-value and n-value.     

公共基础设施特许经营合约与风险治理研究 —以南京长江隧道工程为例

结合南京长江隧道工程特许经营的成功实践,分析特许经营过程中的风险构成;基于公共基础设施 项目特许经营的不完全契约本质,提出恰当的风险治理结构是公共基础设施特许经营能否成功的关键因素。