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11.
On a new formal proof model for RFID location privacy 总被引:2,自引:0,他引:2
We discuss a recently proposed formal proof model for RFID location privacy. We show that protocols which intuitively and in several other models are considered not to be location private, are provably location private in this model. Conversely, we also show that protocols which obviously are location private, are not considered location private in this model.Specifically, we prove a protocol in which every tag transmits the same constant message to not be location private in the proposed model. Then we prove a protocol in which a tag's identity is transmitted in clear text to be weakly location private in the model. 相似文献
12.
Based on the product information structure related to the Manufacturing Engineering Reference Model, a method for variant-based cost estimation is proposed. The structure defines a product in terms of elements and their relations. The elements and their properties constitute product characteristics that can be used to compare products. For proper use in different engineering processes, the product characteristics are related to the four cost drivers - geometry, material, processes and production planning. The main advantage of the proposed method is a more flexible way of defining and valuing product characteristics without the use of rigid product classes and codes. 相似文献
13.
Water sorption and dynamical properties of bread crust were studied using gravimetric sorption experiments. Water uptake and loss were measured while relative humidity (RH) was step-wise in- or decreased. Experimental results were compared with Fickian diffusion models and empirical models like the exponential and power-law model. From comparison of experimental sorption curves and the power-law model for short times it followed for all bread crust that the diffusional coefficient n is close to one. It turned out that this is not due to so-called case II diffusion and water transport that is limited by relaxation of the solid material but due to the fact that RH did not instantaneously but gradually increased to the set value.Sorption curves of isotherm experiments could be best described by the Fickian diffusion model for low RH and by the exponential model for large RH. Transport rates depend on moisture content and show a maximum around RH = 0.7, corresponding to a water mass fraction ω1 = 0.12. Diffusion rates could be well described by free volume theory up to the maximum, but this theory could not explain the strong decrease at higher ω1. Indications for a local glass-rubber transition at room temperature were found near a water mass fraction ω1 ≈ 0.09. This corresponds very well to the start of the crisp–non-crisp transition as measured by a sensory panel, but not to the glass-rubber transition at ω1 ≈ 0.12 as measured by other techniques like Differential Scanning Calorimetry. So it seems that more than one glass-rubber like transitions may be important to describe the properties of heterogeneous cellular food systems. 相似文献
14.
Sijtsema S Linnemann A van Gaasbeek T Dagevos H Jongen W 《Critical reviews in food science and nutrition》2002,42(6):565-581
Consumer wishes have to be translated into product characteristics to implement consumer-oriented product development. Before this step can be made, insight in food-related behavior and perception of consumers is necessary to make the right, useful, and successful translation. Food choice behavior and consumers' perception are studied in many disciplines. Models of food behavior and preferences therefore were studied from a multidisciplinary perspective. Nearly all models structure the determinants related to the person, the food, and the environment. Consequently, the overview of models was used as a basis to structure the variables influencing food perception into a model for consumer-oriented product development. To this new model, referred to as food perception model, other variables like time and place as part of consumption moment were added. These are important variables influencing consumers' perception, and therefore of increasing importance to consumer-oriented product development nowadays. In further research, the presented food perception model is used as a tool to implement successful consumer-oriented product development. 相似文献
15.
用静态法测定了仲丁醇—水体系在0.5MPa压力下的恒压气液平衡数据。用Heringon方法检验数据的热力学一致性,表明实测数据可靠。作者探讨了NRTL、UNIQUAC、ASOG和UNIFAC模型对该体系的关联和予测,并对各方程的拟合结果进行了分析。 相似文献
16.
Ton J. J. van den Boom Miguel Ayala Botto Peter Hoekstra 《International journal of systems science》2013,44(10):639-650
This paper shows how the solution of the standard predictive control problem can be recast as a continuous function of the state, the reference signal, the noise and the disturbances, and hence can be approximated arbitrarily closely by a feed-forward neural network. The existence of such a continuous mapping eliminates the need for linear independency of the active constraints, and therefore the resulting analytic constrained predictive controller will combine constraint handling with speed while being applicable to fast and complex control systems with many constraints. The effectiveness of the proposed controller design methodology is shown for a simulation example of an elevator model and for a real-time laboratory inverted pendulum system. 相似文献
17.
Fatty acid profiles and antioxidants of organic and conventional milk from low‐ and high‐input systems during outdoor period 下载免费PDF全文
18.
介绍了开发的全数字交流伺服系统的组成、基本原理及软、硬件结构。通过与模拟交流伺服系统的比较,说明了全数字交流伺服系统可编程能力强、系统稳定性好、系统性能提高等特点。 相似文献
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20.
Dr. Alessia Amore Kim Wals Evelyn Koekoek Rieuwert Hoppes Mireille Toebes Prof. Ton N. M. Schumacher Dr. Boris Rodenko Prof. Huib Ovaa 《Chembiochem : a European journal of chemical biology》2013,14(1):123-131
Incorporation of cleavable linkers into peptides and proteins is of particular value in the study of biological processes. Here we describe the synthesis of a cleavable linker that is hypersensitive to oxidative cleavage as the result of the periodate reactivity of a vicinal amino alcohol moiety. Two strategies directed towards the synthesis of a building block suitable for solid‐phase peptide synthesis were developed: a chemoenzymatic route, involving L ‐threonine aldolase, and an enantioselective chemical route; these led to α,γ‐diamino‐β‐hydroxybutanoic acids in diastereoisomerically mixed and enantiopure forms, respectively. Incorporation of the 1,2‐amino alcohol linker into the backbone of a peptide generated a conditional peptide that was rapidly cleaved at very low concentrations of sodium periodate. This cleavable peptide ligand was applied in the generation of MHC exchange reagents for the detection of antigen‐specific T cells in peripheral blood cells. The extremely low concentration of periodate required to trigger MHC peptide exchange allowed the co‐oxidation of methionine and disulfide residues to be avoided. Conditional MHC reagents hypersensitive to periodate can now be applied without limitations when UV irradiation is undesired or less practical. 相似文献