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Industry stakeholders and Internet experts generally agree that networks using Internet Protocol version 6 (IPv6), an Internet
communications standard which is being promoted strongly by many parties, would be technically superior to today’s networks,
which are largely based on IPv4. The improvements designed for IPv6 could provide numerous benefits to Internet users, network
administrators, and applications developers; among these potential benefits are cost reductions due to improved security and
increased efficiency, improvements to existing products and services, and innovations leading to new products and services.
However, there is wide disagreement about the characteristics and timing of benefits associated with IPv6, and the costs associated
with the transition could be substantial. In this paper, we will discuss the likely costs of a transition to IPv6 for the
major stakeholders and the potential benefits. Subsequently, we will introduce the cost impact of an accelerated adoption
case and discuss potential ways in which the government could become involved in the process.
This paper is based on a broader study funded by the National Telecommunications and Information Administration (NTIA) and
National Institute of Standards and Technology (NIST). We wish to thank Greg Tassey, Fred Lee, Tim Sloan, B. Keith Fulton,
John Streck, and Baran Erkel for comments and suggestions on earlier versions of this paper. 相似文献
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E L Rowan J B Rowan P Langelier 《The Bulletin of the American Academy of Psychiatry and the Law》1990,18(1):79-83
In only nine of approximately 600 cases of child molestation in New Hampshire and Vermont was the perpetrator found to be a woman. Case histories and some testing data show a history of sexual assault as a child, frequent offense in the company of a dominant male partner, and a major disinhibition as a result of severe character disorder or limited intelligence. These factors not only interfered with maternal bonding and nurturing behavior but also contributed to suspension of judgment about the appropriateness of sexual contact with children. 相似文献
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The toxicological findings of a multi-drug related fatal poisoning are described here. A 35-year-old Caucasian male found dead on the kitchen floor was a known user of abused drugs and had been taking aspirin alone or in combination with phenacetin and caffeine for the relief of joint pains. The gross examination of the organs at autopsy revealed slight grooving of the uncus and various stages of necrosis in the renal papillae. Histological examination confirmed the gross appearance of pulmonary congestion and edema, cerebral edema and interstitial nephritis of the tubules. Toxicological evaluation of the blood and urine samples disclosed the presence of propoxyphene (51 and 250 mg/l), salicylate (185 and 2750 mg/l), caffeine (16 and 37 mg/l), and phenacetin (9.6 and 20 mg/l). Furthermore, acetaminophen also was present in the plasma (54 mg/l) and urine. A gas liquid chromatographic method for simultaneous analysis of phenacetin and caffeine utilizing a nitrogen phosphorus detector was proposed. 相似文献