Heisenberg Groups as Platform for the AAG key-exchange protocol

Garber, Kahrobaei, and Lam studied polycyclic groups generated by number field as platform for the AAG key-exchange protocol. In this paper, we discuss the use of a different kind of polycyclic groups, Heisenberg groups, as a platform group for AAG by submitting Heisenberg groups to one of AAG's major attacks, the length-based attack.Comment: arXiv admin note: text overlap with arXiv:1305.054

State Prescription Drug Price Web Sites: How Useful to Consumers?

Compares ten sites and identifies key limitations due to data omissions, gaps between insured and uninsured consumers, and varied program implementation. Presents alternative policy options such as requiring price lists from pharmacies

Limited Options to Manage Specialty Drug Spending

Outlines rising trends in costs of and spending on specialty drugs; health plans' efforts to curb specialty drug spending, including patient cost sharing and utilization management; and efforts to integrate medical and pharmaceutical coverage

Striking Jump in Consumers Seeking Health Care Information

Examines shifts in how Americans seek health information from sources other than their doctors. Looks at growing Internet use and information-seeking for others, education as a factor, and the impact of information-seeking on perceptions of health issues

Word of Mouth and Physician Referrals Still Drive Health Care Provider Choice

Examines how consumers choose physicians, specialists, or medical facilities, including the use of physician referrals, word-of-mouth recommendations, health plan information, and the Internet. Explores implications for consumer-directed health care

Financial and Health Burdens of Chronic Conditions Grow

Points to rising rates of chronic conditions and obesity; growing numbers of patients with problems paying medical bills, even with insurance; and contributing factors such as declining private coverage and delays in accessing care. Outlines implications

Iron Smelting Slag Formation at Tell Hammeh (Al-Zarqa), Jordan

3-7 May, 200

Study of spread spectrum multiple access systems for satellite communications with overlay on current services

The feasibility of using spread spectrum techniques to provide a low-cost multiple access system for a very large number of low data terminals was investigated. Two applications of spread spectrum technology to very small aperture terminal (VSAT) satellite communication networks are presented. Two spread spectrum multiple access systems which use a form of noncoherent M-ary FSK (MFSK) as the primary modulation are described and the throughput analyzed. The analysis considers such factors as satellite power constraints and adjacent satellite interference. Also considered is the effect of on-board processing on the multiple access efficiency and the feasibility of overlaying low data rate spread spectrum signals on existing satellite traffic as a form of frequency reuse is investigated. The use of chirp is examined for spread spectrum communications. In a chirp communication system, each data bit is converted into one or more up or down sweeps of frequency, which spread the RF energy across a broad range of frequencies. Several different forms of chirp communication systems are considered, and a multiple-chirp coded system is proposed for overlay service. The mutual interference problem is examined in detail and a performance analysis undertaken for the case of a chirp data channel overlaid on a video channel