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101.
匿名代理签名方案的研究与改进 总被引:6,自引:1,他引:6
对谷利泽等提出的匿名代理签名方案进行密码学分析,指出该方案是不安全的,不能抵抗原签名人的伪造攻击和公钥替换攻击,并给出改进的匿名代理签名方案。改进的方案具有不可否认性,以及抵抗原签名人的伪造攻击和公钥替换攻击等优点。 相似文献
102.
最近陈少真等人提出了一种具有前向安全和有效撤销成员性质的群签名方案,该方案通过在签名中增加一个验证取消展示实现对成员的撤销。分析了陈方案设计的缺陷,给出了一种改进的成员撤销算法。在强RSA和离散对数假设下,证明了改进方案的有效性和安全性。 相似文献
103.
Consumer perceptions of traceability: A cross-national comparison of the associated benefits 总被引:4,自引:0,他引:4
Wendy van Rijswijk Lynn J. Frewer Davide Menozzi Giusi Faioli 《Food quality and preference》2008,19(5):452-464
Consumer perceptions regarding traceability were investigated by means-end-chain laddering. Consumers in four European countries were questioned about the benefits they associate with traceability related attributes. The benefits consumers associate with traceability are in terms of health, quality, safety and control, of which the latter was associated with trust and confidence. These benefits were similarly important in the countries investigated. Cross-national differences were also observed. Importantly, both quality and safety were shown to be related to traceability in the consumers′ minds with quality implying safety. The results show that traceability may contribute to improving consumer confidence. The most important aspects of traceability which should be incorporated into communication with consumers are discussed. 相似文献
104.
Ke-Sheng Wang 《先进制造进展(英文版)》2014,2(2):106-120
In the wake of globalization,many modern manufacturing companies in Norway have come under intense pressure caused by increased competition,stricter government regulation,and customer demand for higher value at low cost in a short time.Manufacturing companies need traceability,which means a real-time view into thenproduction processes and operations.Radio frequency identification(RFID) technology enables manufacturing companies to gain instant traceability and visibility because it handles manufactured goods,materials and processes transparently.RFID has become an important driver in manufacturing and supply chain activities.However,there is still a challenge in effectively deploying RFID in manufacturing.This paper describes the importance for Norwegian manufacturing companies to implement RFID technology,and shows how the intelligent and integrated RFID(n-RFID) system,which has been developed in the Knowledge Discovery Laboratory of Norwegian University of Science and Technology,provides instant traceability and visibility into manufacturing processes.It supports the Norwegian manufacturing industries survive and thrive in global competition.The future research work will focus on the field of RFID data mining to support decision-making process in manufacturing. 相似文献
105.
Robotization in fruit grading system 总被引:1,自引:0,他引:1
A grading robot system, which automatically provides fruits from containers and inspects all sides of the fruits was developed.
The robot system consists of two fruit providing robots and a grading robot. Both robots had 3 DOF Cartesian coordinate manipulators,
and 12 suction pads as end-effectors for transporting fruits. The grading robot had 12 color TV cameras, and 28 lighting devices
as a machine vision system. The grading robot sucked 12 fruits up at a time and 12 bottom images of all the fruits were acquired
during the manipulator moving from a halfway stage to carriers on a conveyor line. Before releasing the fruits to the carriers,
4 side images of each fruit were acquired by rotating the suction pads for 270°. The stroke of the manipulators was about
1.2 m and it took about 4.3 s to move back to the initial position that meant that this robot could grade three fruits per
second. This grading robot system made following effects: (1) Labor substitution, (2) Objective grading operation without
human subjective judgment, (3) Data accumulation on fruit grading for traceability and farming guidance to producer. 相似文献
106.
Palmiro Poltronieri Oscar Fernando D’Urso Giuseppe Blaiotta Maria Morea 《Food Analytical Methods》2008,1(3):171-180
Dot blot and deoxyribonucleic acid (DNA) array hybridization assays for the traceability of Lactobacillus species in food have been developed to monitor and validate typical food products. A primer set was designed to amplify the
540-bp region located at +157 of the tuf (Elongation factor Tu) gene of the Lactobacillus genus. An oligonucleotide array, containing 73 Lactobacillus species-specific tuf sequences representing 21 species, was developed and tested for identifying L. paracasei, L. rhamnosus, L. plantarum, and L. buchneri. We also tested a rapid screening method for monitoring the species present in airy samples. Dot blot hybridization identified
polymerase chain reaction amplicons immobilized on nylon membranes, using six tuf-based cyanine-3-labeled 18-mer oligonucleotides, specific for L. paracasei, L. zeae, L. fermentum, L. plantarum, L. rhamnosus, and L. buchneri. This method discriminates between multiple species of Lactobacilli isolated directly from cheese samples, simultaneously.
The tuf gene sequences, verified here with the DNA array method and used in dot blot hybridization, were shown to be a reliable tool
for the simultaneous detection and differentiation of four Lactobacillus species. The hybridization techniques developed in this study may be useful in food processing and the analysis of food origin
traceability. 相似文献
107.
108.
该文对谷利泽(2005)等人提出的一种新型的匿名代理签名方案进行密码分析,指出此方案是不安全的,它无法抵抗原始签名人的伪造攻击,并给出了4种攻击方法。针对此方案的缺陷,提出了两种改进方案,并证明改进后的方案是安全的,可抵抗原始签名人恶意的伪造攻击。 相似文献
109.
《Mechatronics》2014,24(7):763-774
The design of mechatronic systems involves several technical and scientific disciplines. It is often difficult to anticipate, at the outset, the consequences of design decisions on the ultimate effectiveness of such complex systems, in which case the evaluation process is required to support the designers each time engineering choices must be made or justified. Since designers may belong to different technical and scientific cultures however, their understanding of both the design stakes and the evaluation process is too often biased. Moreover, design choices take place in an uncertain context and according to multiple criteria, some of which may be contradictory. In order to track the consequences of design decisions, we are proposing a conceptual data model to perform evaluations within the MBSE framework of Systems Engineering. We then proceed by relying on the relationships demonstrated by such a model to identify the potential impacts of design choices on future product performance. Since data available during the conceptual phase of the design are typically uncertain or imprecise, an original research protocol is extended to a qualitative impact analysis for the purpose of highlighting the most promising alternative system design solutions (ASDS). An example in the mechatronics field serves to illustrate our proposals. 相似文献