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PRIMARY PREVENTIVE HEALTH CARE AMONG INJECTION DRUG USERS, OTHER SUSTAINED DRUG USERS, AND NON-USERS [PDF]

Substance Use and Misuse, 2001
The primary objective of this paper is to investigate the relationship between sustained illicit drug use and the utilization of primary preventive health care. Data from 1254 African-American, Hispanic Latino, and non-Hispanic Latino white men and women
Jesus Sanchez, Dale D Chitwood, Clyde B Mccoy   +2 more
exaly   +2 more sources

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Nonquiet primary user detection scheme

2011 6th International ICST Conference on Communications and Networking in China (CHINACOM), 2011
This paper proposes a nonquiet primary user detection scheme in cognitive radio networks. This scheme can realize cyclostationary feature detection on the condition that the secondary user has same classification and cycle frequency as the primary user.
Zhaoxia Song, Zheng Zhou 0001, Xuan Sun, Yabin Ye   +3 more
openaire   +1 more source

UAV Mapping for Multiple Primary Users Localization

2020 28th European Signal Processing Conference (EUSIPCO), 2021
The unique features of unmanned aerial vehicles (UAVs) extend a large number of existing technologies into environments that are not suitable for on-site operations. Localization, a critical basis of many applications such as cognitive radio and first response networks, can benefit UAV technology as well. In such scenarios, an underinvestigated problem
Zhuyin Li, Andrea Giorgetti, Sithamparanathan Kandeepan   +2 more
openaire   +2 more sources

Locating the primary attention focus of the user

1993
First, a signal detection experiment was carried out to estimate the maximal distance between the primary attention focus of users and the screen position of visual feedback (e.g. messages). The results indicate that the maximal distance between the primary attention focus and the position of visual feedback should not exceed 3. Second, to pinpoint the
Matthias Rauterberg, Christian Cachin
openaire   +1 more source

Performance of an opportunistic multi-user cognitive network with multiple primary users

2014 IEEE Wireless Communications and Networking Conference (WCNC), 2014
Consider a multi-user underlay cognitive network where multiple cognitive users, having limited peak transmit power, concurrently share the spectrum with a primary network with multiple users. The channel between the secondary network is assumed to have independent but not identical Nakagami-m fading.
Fahd Ahmed Khan, Kamel Tourki, Mohamed-Slim Alouini, Khalid A. Qaraqe   +3 more
openaire   +1 more source

Optimizing Secondary User Performance under Delay Constraint for Primary User

2017 IEEE Wireless Communications and Networking Conference (WCNC), 2017
We consider a cognitive radio network with one primary (PU), one secondary user (SU), and two distinct destinations. SU not only exploits the idle time slots (i.e. PU is not transmitting) to send its own packets, but also interfere with the PU with a certain probability that is optimized to maximize the stable throughput of the SU under a delay ...
Mohamed Salman, Lijun Chen 0001
openaire   +1 more source

Sharing with Primary Spectrum Users

2011
RF spectrum has to be shared, not only between systems and applications of similar purpose and regulatory status, but also between primary spectrum users and commodity wireless systems. The former are deemed to merit protection from interference caused by the latter. This is an example of vertical spectrum sharing between dissimilar systems.
Jan Kruys, Luke Qian
openaire   +1 more source

Secondary User Satisfying Primary User Rate Constraint for Cognitive Radio

2015 IEEE 82nd Vehicular Technology Conference (VTC2015-Fall), 2015
In this paper, we propose a generalized model for underlay based cognitive radio (CR) that is based on the information theoretic interference channel model. Utilizing the achievable rate region for the two user interference channel proposed by Han and Kobayashi, we establish achievable rates for the unlicensed or the Secondary User (SU) that depends ...
Aaqib Patel, S. N. Merchant, Md. Zafar Ali Khan, Uday B. Desai   +3 more
openaire   +1 more source

Secondary User Friendly TDMA Scheduling for Primary Users in Cognitive Radio Networks

GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009
Cognitive radio technology is widely accepted as an efficient approach to solve the problem that the wireless spectrum has been getting scarcer and scarcer due to the rapid growth in the ubiquitous wireless applications. Several cognitive medium access control (MAC) protocols have been proposed for the secondary users (non-licensed users) to take ...
Hang Su 0007, Xi Zhang 0005
openaire   +1 more source