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41.
Stephen M. Matyas 《Journal of Cryptology》1991,3(2):113-136
A method is presented for controlling cryptographic key usage based on control vectors. Each cryptographic key has an associated control vector that defines the permitted uses of the key within the cryptographic system. At key generation, the control vector is cryptographically coupled to the key by way of a special encryption process. Each encrypted key and control vector are stored and distributed within the cryptographic system as a single token. Decryption of a key requires respecification of the control vector. As part of the decryption process, the cryptographic hardware verifies that the requested use of the key is authorized by the control vector. This article focuses mainly on the use of control vectors in cryptosystems based on the Data Encryption Algorithm. 相似文献
42.
No authorship indicated 《Canadian Metallurgical Quarterly》2004,59(8):728
Provides the biography of Dante Cicchetti and announces that he has received the APA Award for Distinguished Senior Career Contributions to Psychology in the Public Interest (2004) for his seminal role in bridging theory, research, and practice by fostering the emergence and coalescence of the field of developmental psychopathology. A selected bibliography is also provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Mihir Bellare Adriana Palacio 《Applicable Algebra in Engineering, Communication and Computing》2006,16(6):379-396
Key-insulated encryption schemes use a combination of key splitting and key evolution to protect against key exposure. Existing
schemes, however scale poorly, having cost proportional to the number t of time periods that may be compromised by the adversary, and thus are practical only for small values of t. Yet in practice t might be large.
This paper presents a strongly key-insulated encryption scheme with optimal threshold. In our scheme, t need not be known in advance and can be as large as one less than the total number of periods, yet the cost of the scheme
is not impacted. This brings key-insulated encryption closer to practice. Our scheme is based on the Boneh-Franklin identity-based
encryption (IBE) scheme [9], and exploits algebraic properties of the latter.
Another contribution of this paper is to show that (not strongly) key-insulated encryption with optimal threshold and allowing
random-access key updates (which our scheme and all others known allow) is equivalent to a restricted form of IBE. This means
that the connection between key-insulated encryption and IBE is not accidental.
Supported in part by NSF grants CCR-0098123, ANR-0129617 and CCR-0208842, and by an IBM Faculty Partnership Development Award.
Supported in part by an NSF graduate fellowship. 相似文献
44.
Renewable energy systems: A societal and technological platform 总被引:1,自引:0,他引:1
Today, the analysis of renewable energy places the emphasis on the technological and economic attributes with social and environmental impact assessment providing for a rather static, narrow frame of analysis. The participation and response of social actors and other stakeholders is usually of a traditional type, with consultation documents and public meetings, collection of complaints and suggestion schemes. This often encourages parochialism and an over-concentration on relatively trivial issues. It is, therefore, imperative to establish a new participatory planning platform to incorporate the wider socio-economic aspects of renewable energy systems and to provide for an operational analytical decomposition of them. In this work the issue of decomposition analysis is clarified, and a new agenda for the societal and technological decomposition analysis of renewable energy systems is developed. A case study is disclosed to present the relevance of the established platform for integrated (renewable) energy systems planning. Innovative aspects comprise of the simultaneous inclusion of decision analysis and social acceptance methods and tools in concert with the related public participation techniques. 相似文献
45.
首尔地面公交系统改革的成功经验 总被引:1,自引:0,他引:1
随着经济、人口的快速发展,首尔开展了一次针对地面公交系统的成功而深刻的变革。其中包括组建以公众参与为基础的公交系统改革公民委员会,形成了“以线路连接为导向的公交系统”,采用新型公交智能卡、票价新制度以及信息一体化的管理系统。 相似文献
46.
本文提出了一种新的4级密钥管理方案.该方案通过一个密码操作核心的精心设计,为各用户使用系统的各种功能提供了方便的手段,同时确保了系统的安全性.此外,该方案还大大降低了系统开发费用和保密通信的复杂度.因此,该方案克服了以往方案中的缺陷,已被正在开发的系统SUTU采用. 相似文献
47.
The infrastructure renewal program at MIT consists of a large number of projects with an estimated budget that could approach $1 billion. Infrastructure renewal at the Massachusetts Institute of Technology (MIT) is the process of evaluating and investing in the maintenance of facility systems and basic structure to preserve existing campus buildings. The selection and prioritization of projects must be addressed with a systematic method for the optimal allocation of funds and other resources. This paper presents a case study of a prioritization method utilizing multi-attribute utility theory. This method was developed at MIT's Department of Nuclear Engineering and was deployed by the Department of Facilities after appropriate modifications were implemented to address the idiosyncrasies of infrastructure renewal projects and the competing criteria and constraints that influence the judgment of the decision-makers. Such criteria include minimization of risk, optimization of economic impact, and coordination with academic policies, programs, and operations of the Institute. A brief overview of the method is presented, as well as the results of its application to the prioritization of infrastructure renewal projects. Results of workshops held at MIT with the participation of stakeholders demonstrate the feasibility of the prioritization method and the usefulness of this approach. 相似文献
48.
This article is concerned with various arithmetic operations inGF(2
m
). In particular we discuss techniques for computing multiplicative inverses and doing exponentiation. The method used for
exponentiation is highly suited to parallel computation. All methods achieve much of their efficiency from exploiting a normal
basis representation in the field. 相似文献
49.
城市规划行政的制约机制——公众参与 总被引:7,自引:0,他引:7
通过对我国城市规划编制过程和实施管理过程中“非理性”因素及其产生根源的分析,提出改进城市规划行政模式,阐述城市规划公众参与的必要性,同时阐明现阶段公众参与的重点。 相似文献
50.
王茜 《数码设计:surface》2012,(5):104-106
公益产品设计近年来备受社会瞩目,其构想的价值毋庸置疑,然而,在设计中,一些思想未必成熟,各方面因素考虑不周,设计出的产品不仅难以实现公益,甚至出现南辕北辙的无奈。把握公益产品设计的正确方向,使得产品设计能够真正做到公益的效果,对于参与公益产品设计的企业和设计者而言是当务之急。 相似文献