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1.
Software agents that play a role in E-commerce and E-government applications involving the Internet often contain information about the identity of their human user such as credit cards and bank accounts. This paper discusses whether this is necessary: whether human users and software agents are allowed to be anonymous under the relevant legal regimes and whether an adequate interaction and balance between law and anonymity can be realised from both the perspective of Computer Systems and the perspective of Law.This paper is an extended and fully revised version of Brazier, Kubbe, Oskamp and Wijngaards (2002) and Brazier, Oskamp, Prins, Schellekens and Wijngaards (2003).  相似文献   
2.
The increasing demand for biomass for energy use is further escalating existing food security risks. Managing these risks is a task for global institutions. These should ensure timely investment in the world’s capacity for producing biomass and balance the use of this biomass for foods and for non-foods. To achieve this, institutional arrangements for global food markets must fulfil two important goals: reduce the short-term price instability of food markets and prevent a structural scarcity of food in the long term. This paper analyses how agro-food markets, energy markets and biofuel markets are currently regulated. As this regulation is ill-suited to manage food price instabilities and balance food and non-food use of biomass, new institutions need to be put in place. A coordinated system of global commodity management — not unlike the Commodity Control Organization proposed by Keynes for the post-WWII era — is proposed to deal with these coming challenges.  相似文献   
3.
In this paper, we highlight considerations for synchronization issues in body area networks. Requirements for the synchronization accuracy in body area networks depend on the application at hand. Synchronization may be needed for power management, sample ordering, calculation of stimulus responses and for sensor fusion. This paper provides a theoretical exercise to help understand the accuracy required for typical human motion sensing. It gives an overview of various synchronisation strategies used and implemented in prototype systems. Lessons learnt from practical implementations using Bluetooth, an IEEE 802.15.4 proprietary network and Nanonet are presented to illustrate the principles involved. The discussion provides some considerations and the requirements for typical WBAN applications.  相似文献   
4.
An in vitro method was developed to determine the rate of drug release from a liposome formulation. Liposome formulation containing metaproterenol sulfate was evaluated for release of the drug over a 24-hour period in an end-over-end tumbler device. Drug release appeared to be a function of all the operating parameters, such as rotational speed of the end-over-end tumbler, temperature of suspension, and the geometry of sample container that is placed in the end-over-end tumbler device.  相似文献   
5.
The extent to which nanoscale‐engineered systems cross intact human skin and can exert pharmacological effects in viable epidermis is controversial. This research seeks to develop a new lipid‐based nanosome that enables the effective delivery of siRNA into human skin. The major finding is that an ultraflexible siRNA‐containing nanosome—prepared using DOTAP, cholesterol, sodium cholate, and 30% ethanol—penetrates into the epidermis of freshly excised intact human skin and is able to enter into the keratinocytes. The nanosomes, called surfactant‐ethanol‐cholesterol‐osomes (SECosomes), show excellent size, surface charge, morphology, deformability, transfection efficiency, stability, and skin penetration capacity after complexation with siRNA. Importantly, these nanosomes have ideal characteristics for siRNA encapsulation, in that the siRNA is stable for at least 4 weeks, they enable highly efficient transfection of in vitro cultured cells, and are shown to transport siRNA delivery through intact human skin where changes in the keratinocyte cell state are demonstrated. It is concluded that increasing flexibility in nanosomes greatly enhances their ability to cross the intact human epidermal membrane and to unload their payload into targeted epidermal cells.  相似文献   
6.
上海世博公园不仅是2010年上海世博园区核心公共空间,更是上海中心城区及沿黄浦江的一块结构型公园绿地。上海世博公园绿地要承载超高密度人流,交通系统规划设计是关键。本文围绕构筑多模式的现代复合交通体系,在分析公园外部交通条件的基础上,对绿地内部道路交通系统的合理布局做了阐述,同时对集散空间、游船停泊系统、无障碍设计等交通设施的设计进行了分析介绍。  相似文献   
7.
创造·展示和谐城市——上海世博公园实施方案解析   总被引:4,自引:0,他引:4  
通过对中国2010上海世博园区总体规划的分析介绍,重点解析了上海世博公园实施方案的规划理念、设计构思、结构布局、功能分区等。  相似文献   
8.
We study different possibilities to use adaptive optics (AO) and phase diversity (PD) together in a jointly optimized system. The potential of the joint system is demonstrated through numerical simulations. We find that the most significant benefits are obtained from the improved deconvolution of AO-corrected wavefronts and the additional wavefront sensor (WFS) information that reduces the computational demands of PD algorithms. When applied together, it is seen that the image error can be reduced by 20% compared to traditional PD, working with one focused and one defocused camera image, and the computational load is reduced by a factor of 20 compared to a more reliable PD algorithm requiring more camera images. In addition, we find that the system performance can be optimized by adjusting the magnitude of the applied diversity wavefronts.  相似文献   
9.
Resonant optical antennas are ideal for nanoscale nonlinear optical interactions due to their inherent strong local field enhancement. Indeed second- and third-order nonlinear response of gold nanoparticles has been reported. Here we compare the on- and off-resonance properties of aluminum, silver, and gold nanoantennas, by measuring two-photon photoluminescence. Remarkably, aluminum shows 2 orders of magnitude higher luminescence efficiency than silver or gold. Moreover, in striking contrast to gold, the aluminum emission largely preserves the linear incident polarization. Finally, we show the systematic resonance control of two-photon excitation and luminescence polarization by tuning the antenna width and length independently. Our findings point to aluminum as a promising metal for nonlinear plasmonics.  相似文献   
10.
Reasons are given why the axial dispersion in a gas flowing through a packed bed may be influenced by the elasticity - or compressibility - of the fluid. To support this hypothesis, experiments have been done in a packed column at pressures from 0.13 to 2.0 MPa. The elasticity E of a gas is proportional to the pressure P and the compressibility to 1/P. The axial dispersion coefficients as determined were found to be a function of the pressure in the packed bed in the turbulent flow region of 3 < Rep < 150 if the Bodenstein number is plotted as a function of the particle Reynolds number. This is shown to be an artifact. The pressure influence is eliminated, if Bom, ax is plotted versus the ratio of the kinetic forces over the elastic forces ?u2/E. Regrettably, Bom, ax seems to be independent of ?u2/E. For the moment we only can conclude that Bom, ax in the turbulent region is a unique function of the velocity of the gas which flows through the packed bed. Although the fact that a constant Bo value is obtained when plotted against ?u2/E, the experimental results are so intriguing we wanted to make them public already now. The experimental work proceeds.  相似文献   
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