selective availability

简明释义

选择可用性

英英释义

例句

1.During times of national security, the government might impose selective availability on satellite data.

在国家安全时期，政府可能会对卫星数据施加选择性可用性。

2.The GPS system used selective availability to limit the accuracy of civilian signals.

GPS系统使用选择性可用性来限制民用信号的精确度。

3.Many users were frustrated by the selective availability of GPS services during critical missions.

在关键任务期间，许多用户对GPS服务的选择性可用性感到沮丧。

4.The military often uses selective availability to ensure that only authorized personnel have access to precise location data.

军方通常使用选择性可用性以确保只有授权人员可以访问精确的位置信息。

5.The implementation of selective availability can lead to discrepancies in navigation for commercial pilots.

实施选择性可用性可能导致商业飞行员导航中的差异。

作文

In the realm of global positioning systems (GPS), the term selective availability refers to a method employed by the United States government to intentionally degrade the accuracy of GPS signals available to civilian users. This practice was primarily implemented to ensure that military operations would not be compromised by adversaries having access to precise navigational data. The concept of selective availability highlights the intersection of technology and national security, illustrating how advancements in navigation can be influenced by geopolitical considerations.Before its discontinuation in 2000, selective availability resulted in a significant reduction of GPS accuracy for civilian users, often leading to errors of up to 100 meters. This limitation posed challenges for various applications, including aviation, maritime navigation, and land-based transportation. As a consequence, many industries that relied on accurate GPS data were forced to seek alternative solutions or invest in expensive equipment capable of mitigating the effects of selective availability.The decision to eliminate selective availability marked a pivotal moment in the evolution of GPS technology. It reflected a growing recognition of the importance of reliable navigational tools for civilian purposes, particularly as the use of GPS expanded beyond military applications into everyday life. With the advent of smartphones and other portable devices, the demand for accurate location data surged, prompting the government to reconsider its policy on selective availability.In the absence of selective availability, GPS technology has flourished. Today, GPS is integral to numerous sectors, including transportation logistics, emergency services, and even personal fitness tracking. The removal of intentional inaccuracies has enabled innovations such as real-time traffic navigation, which relies on precise data to provide users with the best routes available, thereby enhancing overall efficiency.However, the discussion surrounding selective availability raises important questions about the balance between national security and public accessibility to technology. While the discontinuation of this practice has undoubtedly benefited civilian users, it also underscores the potential vulnerabilities that arise when critical technologies are made widely accessible. For instance, the very precision that civilians enjoy today could be exploited by malicious actors if not properly managed.Looking forward, it is essential to consider how future developments in GPS technology might be influenced by the lessons learned from selective availability. As global tensions continue to evolve, governments may once again grapple with the implications of providing unrestricted access to precise navigational data. The need for robust cybersecurity measures and contingency plans will become increasingly vital to safeguard against potential threats while ensuring that civilians can benefit from advancements in technology.In conclusion, the concept of selective availability serves as a reminder of the delicate balance between technological advancement and national security. Its historical significance sheds light on the complexities involved in managing critical infrastructure and the ongoing dialogue about how best to protect both citizens and national interests. As GPS technology continues to develop, the legacy of selective availability will undoubtedly influence the policies and practices that govern its use in the future.

在全球定位系统（GPS）的领域，术语选择性可用性指的是美国政府采用的一种方法，故意降低提供给民用用户的GPS信号的精确度。此做法主要是为了确保军事行动不会受到敌对势力获取精确导航数据的影响。选择性可用性的概念突显了技术与国家安全之间的交叉，说明了导航技术的进步如何受到地缘政治考虑的影响。在2000年之前，选择性可用性导致民用用户GPS精确度显著降低，常常导致误差达到100米。这一限制给航空、海洋导航和陆地交通等多个应用领域带来了挑战。因此，许多依赖于准确GPS数据的行业被迫寻求替代解决方案或投资于能够减轻选择性可用性影响的昂贵设备。取消选择性可用性的决定标志着GPS技术演变中的一个关键时刻。它反映出人们越来越认识到可靠导航工具对民用目的的重要性，尤其是在GPS的使用从军事应用扩展到日常生活的背景下。随着智能手机和其他便携设备的出现，对准确位置数据的需求激增，促使政府重新考虑其关于选择性可用性的政策。在没有选择性可用性的情况下，GPS技术蓬勃发展。如今，GPS在运输物流、紧急服务，甚至个人健身追踪等多个领域都发挥着不可或缺的作用。故意不准确性的消除使得实时交通导航等创新成为可能，该技术依赖于精确的数据为用户提供最佳路线，从而提高整体效率。然而，围绕选择性可用性的讨论引发了关于国家安全与公众技术可及性之间平衡的重要问题。尽管取消这一做法无疑使民用用户受益，但它也强调了当关键技术广泛可用时可能出现的潜在脆弱性。例如，今天公民所享有的精确度如果管理不当，可能会被恶意行为者利用。展望未来，考虑GPS技术未来发展的方向以及如何受到选择性可用性所传达的教训的影响至关重要。随着全球紧张局势的持续演变，各国政府可能会再次面临提供精确导航数据无限制访问的影响。强有力的网络安全措施和应急计划的需求将变得越来越重要，以保护公民利益，同时确保他们能够享受技术进步带来的好处。总之，选择性可用性的概念提醒我们在技术进步与国家安全之间的微妙平衡。其历史意义揭示了管理关键基础设施的复杂性，以及有关如何最好地保护公民和国家利益的持续对话。随着GPS技术的不断发展，选择性可用性的遗产无疑将影响未来治理其使用的政策和实践。