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61.
Through the Preservation of Complex Objects Symposia (POCOS), leading researchers and practitioners have managed to propose strategies for preserving digital art and computer games. The same is not true for the preservation of archaeological visualizations. This article therefore discusses the following question: “Can emulation be employed to effectively preserve obsolete computer visualizations from the Archaeology domain?” Guidelines and test results coming from this work would be of great benefit to the archaeological community, and would contribute knowledge to other research communities, specifically those interested in similar data types/3D visualizations.  相似文献   
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The EU co-funded project Advanced Research Infrastructure for Archaeological Dataset Networking in Europe (ARIADNE) aims to integrate data and services across Europe for the archaeological research community. The Discovery Programme has investigated data holdings and management practices in Irish archaeology, focusing on what information is available in physical and digital forms, approaches to preservation and accessibility, and the challenges and opportunities around dataset networking with Irish archaeological data. While significant work will be required to enable the accessibility expected by researchers now and in future, there is also an opportunity to approach the challenges of digital preservation as a community.  相似文献   
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The digital revolution has changed the daily work of archivists. As a result, archivists have refined their analog practices and initiated new ones to accommodate the unique information creation and access needs of users. While limitless storage and technological obsolescence may be surmountable challenges, appraisal continues to be a necessary component of this preservation enterprise. Macro-appraisal—a top-down functional assessment of an organization’s high-level decision making that defines the enduring value of specific bodies of documentary evidence of these creative or administrative processes—is used to facilitate the management of diverse bodies of born-digital records in archives and special collections.  相似文献   
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In this paper, we consider the problem of flocking and shape‐orientation control of multi‐agent systems with inter‐agent and obstacle collision avoidance. We first consider the problem of forcing a set of autonomous agents to form a desired formation shape and orientation while avoiding inter‐agent collision and collision with convex obstacles, and following a trajectory known to only one of the agents, namely the leader of the formation. Then we build upon the solution given to this problem and solve the problem of guaranteeing obstacle collision avoidance by changing the size and the orientation of the formation. Changing the size and the orientation of the formation is helpful when the agents want to go through a narrow passage while the existing size or orientation of the formation does not allow this. We also propose collision avoidance algorithms that temporarily change the shape of the formation to avoid collision with stationary or moving nonconvex obstacles. Simulation results are presented to show the performance of the proposed control laws.  相似文献   
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本文主要介绍了电热水器的定时保温控制系统的设计.根据系统的特点,设计分为时钟定时部分、温度采集部分和电源控制部分.本设计的时钟设定及显示功能利用PIC16F877A芯片来完成,温度采集部分由温度传感器DS18B20来完成,电源控制部分由继电器来完成,同时利用PIC 16F877A的RB端口来控制电热水器开关及输入调整时间和温度.  相似文献   
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This article uses data from research conducted in the course of writing a book on the needs, wants and characteristics of researchers to examine how researchers view themselves and the research process. As a result of this, the Seven Ages of Research model was developed which categorises a researcher's learning life into a series of discrete stages. The article explores learning needs relevant to each age in the learning life and links them to the development of information literacy. The authors explore the polarisation that exists between what researchers think research is about and what they believe the library can offer them, and suggest that information literacy needs to be seen as involving a change in understanding of, and attitude to, the world of information, as well as the nature of those information needs. Finally, they explore the librarian's role in an e-environment which has changed the way researchers work and identify some of the challenges facing library and information services professionals in the future in supporting researchers throughout their learning lives.  相似文献   
70.
一种多精英保存策略的遗传算法   总被引:4,自引:0,他引:4  
朱灿  梁昔明 《计算机应用》2008,28(4):939-941
根据种子到当前最优点的距离将种群分成两部分,小于或等于某一自适应距离值的种子归入当前最优种群,大于该距离值的次优种子形成次优种群集合。对此两个种群分别按照不同的进化策略协同进化并重组。通过界定最优种群边界来提高遗传算法局部搜索能力,通过对次优种群自适应变异,比较好地平衡种群的“选择压力”和“种群多样性”。数值结果表明了本方法的有效性和稳定性。  相似文献   
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