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11.
Alex Bakman 《Computer Fraud & Security》2003,2003(8):9-11
Imagine this scenario. As a security manager for your organization, your responsibilities include analyzing and applying patches to all Windows servers across the enterprise. Your process is going to each machine and manually evaluating what patches are missing and installing the most critical security patches as soon as possible. How long does this take? One hour per server? Two hours? Maybe more? How many patches are critical? How often do you do it? And, how many servers do you have? It doesn’t take long to do the math to realize that your battle may be a futile one to keep up with the most critical, let alone every, patch that’s released. 相似文献
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To clarify some of the solid-state aspects of cold fusion in deuterated transition metal electrodes, we have carried out first-principles self-consistent total energy calculations for various configurations of atomic and diatomic deuterium inside fcc palladium. We find that the stability of the Pd+D system is controlled by the relative position of the deuterium-inducedantibonding level with respect to the Fermi energy. The equilibrium D-D distance in dense PdD
up to =3 is found to be much larger than the free space value. The calculated Born-Oppenheimer energy surface of diatomic D2 in crystalline palladiuim is shown to have but metastable local minima whose internuclear separation is at least 0.2 Ålarger than that of the isolated D2 molecule. We conclude that D2 incrystalline Pd will have a substantially lower tunneling probability than hitherto thought and that explanation for fusion mechanisms should be sought elsewhere. 相似文献
14.
Phan Alex Truong Phuong Schade Christoph Vasan Aditya Friend James Talke Frank E. 《Microsystem Technologies》2021,27(6):2473-2479
Microsystem Technologies - “Zero drift” behavior of an optical intraocular pressure sensor is studied using an analytical model based on the deflection of a circular membrane. Results... 相似文献
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16.
Long Tran-Thanh Alex Rogers Nicholas R. Jennings 《Autonomous Agents and Multi-Agent Systems》2012,25(2):352-394
This paper reports on the development of a multi-agent approach to long-term information collection in networks of energy harvesting wireless sensors. In particular, we focus on developing energy management and data routing policies that adapt their behaviour according to the energy that is harvested, in order to maximise the amount of information collected given the available energy budget. In so doing, we introduce a new energy management technique, based on multi-armed bandit learning, that allows each agent to adaptively allocate its energy budget across the tasks of data sampling, receiving and transmitting. By using this approach, each agent can learn the optimal energy budget settings that give it efficient information collection in the long run. Then, we propose two novel decentralised multi-hop algorithms for data routing. The first proveably maximises the information throughput in the network, but can sometimes involve high communication cost. The second algorithm provides near-optimal performance, but with reduced computational and communication costs. Finally, we demonstrate that, by using our approaches for energy management and routing, we can achieve a 120% improvement in long-term information collection against state-of-the-art benchmarks. 相似文献
17.
Cookies are the primary means for web applications to authenticate HTTP requests and to maintain client states. Many web applications (such as those for electronic commerce) demand a secure cookie scheme. Such a scheme needs to provide the following four services: authentication, confidentiality, integrity, and anti-replay. Several secure cookie schemes have been proposed in previous literature; however, none of them are completely satisfactory. In this paper, we propose a secure cookie scheme that is effective, efficient, and easy to deploy. In terms of effectiveness, our scheme provides all of the above four security services. In terms of efficiency, our scheme does not involve any database lookup or public key cryptography. In terms of deployability, our scheme can be easily deployed on existing web services, and it does not require any change to the Internet cookie specification. We implemented our secure cookie scheme using PHP and conducted experiments. The experimental results show that our scheme is very efficient on both the client side and the server side.A notable adoption of our scheme in industry is that our cookie scheme has been used by Wordpress since version 2.4. Wordpress is a widely used open source content management system. 相似文献
18.
Summary Monomer modified tall oil fatty acid trimethylolethane medium type of phthalic alkyds made by the High Polymer Alkyd Technique
show improved properties in dry time, mar resistance, and flexibility as compared with monomer modified conventional prepared
systems.
Greater hardness, less color degradation, greater resistance to extended periods at high temperature, and alkali and detergent
resistances result from the urea and melamine resin modifications of tall oil fatty acid High Polymer alkyds than is obtained
with similarly modified conventional alkyds. 相似文献
19.
Alex Mayer Enrique R. Vivoni David Kossak Kathleen E. Halvorsen Agustin Robles Morua 《Water Resources Management》2017,31(15):4731-4744
Participatory modeling workshops were held in Sonora, México, with the goal of developing water resources management strategies in a water-stressed basin. A model of the water resources system, consisting of watershed hydrology, water resources infrastructure, and groundwater models, was developed deliberatively in the workshops, along with scenarios of future climate and development. Participants used the final version of the water resources systems model to select management strategies. The performance of the strategies was based on the reliability of meeting current and future demands at a daily time scale over a year’s period. Pre- and post-workshop surveys were developed and administered. The survey questions focused on evaluation of participants’ modeling capacity and the utility and accuracy of the models. The selected water resources strategies and the associated, expected reliability varied widely among participants. Most participants could be clustered into three groups with roughly equal numbers of participants that varied in terms of reliance on expanding infrastructure vs. demand modification; expectations of reliability; and perceptions of social, environmental, and economic impacts. The wide range of strategies chosen and associated reliabilities indicate that there is a substantial degree of uncertainty in how future water resources decisions could be made in the region. The pre- and post-survey results indicate that participants believed their modeling abilities increased and beliefs in the utility of models increased as a result of the workshops. 相似文献
20.
Phosphorus modification of ZSM-5 leads to extra framework P5+ and probably incorporation of +3 valence state of P in the framework. The resulting system has increased Brønsted acidity. Theoretical calculations also favour the postulate that phosphorus in +3 valence state can be incorporated into the lattice. 相似文献