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排序方式: 共有3058条查询结果,搜索用时 15 毫秒
21.
Razina Z. Seeni Mengjia Zheng Daniel Chin Shiuan Lio Christian Wiraja Mohammad Firdaus Bin Mohd Yusoff William Teck Yeow Koh Yuchun Liu Bee Tin Goh Chenjie Xu 《Advanced functional materials》2021,31(47):2105686
Pain management during dental procedures is a cornerstone for successful daily practice. In current practice, the traditional needle and syringe injection is used to administer local anesthesia. However, the appearance of long needles and the pain associated with it often leads to dental anxiety deterring timely interventions. Microneedles (MNs) have emerged as a minimally invasive alternative to hypodermic needles and shown to be effective in transdermal drug delivery applications. In this article, the potential use of MNs for local anesthesia delivery in dentistry is explored. The development of a novel conductive MN array that can be used in combination with iontophoresis technique to achieve drug penetration through the oral mucosa and the underlying bone tissue is presented. The conductive MN array plays a dual-role, creating micro-conduits and lowering the resistance of the oral mucosa. The reduced tissue resistance further enhances the application of a low-voltage current that is able to direct and accelerate the drug molecules to target the sensory nerves supplying teeth. The successful delivery of lidocaine using this new strategy in a clinically relevant rabbit incisor model is shown to be as effective as the current gold standard. 相似文献
22.
Ahmed H. Abd El‐Malek Fawaz S. Al‐Qahtani Salam A. Zummo Hussein Alnuweiri 《Wireless Communications and Mobile Computing》2016,16(14):2098-2115
In this paper, we examine the impact of antenna correlation on transmit antenna selection with receive maximal ratio combining (TAS/MRC) in multiple‐input multiple‐output multiuser underlay cognitive radio network (MIMO‐MCN) over a Nakagami‐m fading environment. The secondary network under consideration consists of a single source and M destinations equipped with multiple correlated antennas at each node. The primary network composed of L primary users, each of which is equipped with multiple correlated antennas. For the considered underlay spectrum sharing paradigm, the transmission power of the proposed secondary system is limited by the peak interference limit on the primary network and the maximum transmission power at the secondary network. In particular, we derive exact closed‐form expressions for the outage probability and average symbol error rate of the proposed secondary system. To gain further insights, simple asymptotic closed‐form expressions for the outage probability and symbol error rate are provided to obtain the achievable diversity order and coding gain of the system. In addition, the impact of antenna correlation on the secondary user ergodic capacity has been investigated by deriving closed‐form expressions for the secondary user capacity. The derived analytical formulas herein are supported by numerical and simulation results to clarify the main contributions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
23.
24.
Hussein Khalid F. A. Helmy Asmaa O. Mohra Ashraf S. 《Wireless Personal Communications》2022,126(1):871-893
Wireless Personal Communications - This paper proposes a novel design of a software-defined matched filter (MF) for digital receivers of synthetic aperture radar (SAR). The block diagram of the... 相似文献
25.
Almawgani A. H. M. Alhawari Adam R. H. Hindi Ayman Taher Al-Arashi Waled Hussein Al-Ashwal A. Y. 《Multidimensional Systems and Signal Processing》2022,33(2):561-578
Multidimensional Systems and Signal Processing - Digital images are commonly used in steganography due to the popularity of digital image transfer and exchange through the Internet. However, the... 相似文献
26.
Abbas Mehdizadeh Fazirulhisyam Hashim Raja Syamsul Azmir Raja Abdullah Borhanuddin Mohd. Ali 《Wireless Personal Communications》2014,77(3):2195-2212
Group key management is one of the key security issues in multicast networks. The main challenge is to provide a secure group key management method which avoids high key update cost in terms of the number of transmitted keys. In order to achieve low key update cost for group key management, most of the existing methods increase their encryption/decryption cycles which requires a strong cryptographic function. In this paper, a cost-effective key management method is proposed to address the problem of high key update cost without increasing the encryption/decryption cycles. We evaluated our proposed method with existing tree-based methods by using Markov chain and Poisson Arrival Process. Results indicate the efficiency of our proposed method in reducing the key update cost significantly compared to the existing tree-based key management methods. 相似文献
27.
Ibrahim Al-Surmi Mohamed Othman Nor Asila Wati Abdul Hamid Borhanuddin Mohd Ali 《Wireless Networks》2013,19(6):1317-1336
As a network-based localized mobility management protocol, Proxy Mobile IPv6 (PMIPv6) enables a Mobile Host (MH) to roam within a localized domain without MH intervention in the mobility-related signalling. However, the PMIPv6 maintains MH mobility support in a restriction domain. Therefore, whenever the MH roams away from the PMIPv6 domain, its reachability status will be broken-down causing high handover latency and inevitable traffic loss for its communication session. This article proposes a proactive mechanism to mange the MH handover and maintain its data session continually across inter-PMIPv6-domains. The proposed mechanism introduces an intermediate global mobility anchor entity, called, which is responsible to coordinate MH handover as well as redirect its traffic across inter-PMIPv6-domains. Through various simulation evaluations, via ns-2, several experiments were conducted, revealing numerous results that verify the proposed mechanism superior performance over the conventional inter-PMIPv6-domain handover schemes in terms of handover latency, achieved throughput, protocol signalling cost and end-to-end traffic delivery latency. 相似文献
28.
Yaser Pourmohammadi Fallah Samer El-Housseini Hussein Alnuweiri 《Wireless Personal Communications》2008,47(2):235-245
The main service differentiation mechanism introduced by the IEEE 802.11e standard is described in terms of prioritized contention
access. Analyzing the performance and service differentiation ability of each of the priority features of the 802.11e standard
is an important task, and considerable research effort has recently been dedicated to this subject. In this article, we present
a generalized and comprehensive analysis of the prioritized access scheme of the 802.11e standard. Our model corrects and
extends the existing models and considers all priority features of the 802.11e Medium Access Control (MAC) protocol. We consider
an arbitrary number of priority levels, and provide a detailed parametric analysis of the MAC behavior for the main priority
parameters of inter frame spacing, contention window size, and transmission opportunity. We validate the accuracy of our analysis
with simulation experiments.
相似文献
Hussein AlnuweiriEmail: |
29.
Ali Khalid Rasid Mohd Fadlee A. Sali Aduwati Ali Borhanuddin 《Wireless Personal Communications》2020,111(3):1853-1870
Wireless Personal Communications - A prediction-based method is presented to track mobile object and its location in a sensor network area. In recent years, energy consumption and high accuracy... 相似文献
30.
Muhammad Taufiq Mohd Fikri Azli bin Abdullah Deokjai Choi 《Wireless Personal Communications》2011,60(3):431-440
In a wide area campus, a university provides Wireless Local Area Network (WLAN) for users to connect to the Internet. Most
users take advantage of this WLAN benefit by using their laptops. However, the number of smart phone users is growing fast.
Since a smart phone is able to get an Internet connection using WLAN, users can use their smart phones without having to pay
for a cellular operator. Users tend to use their smart phones more, due to their higher mobility compared to a laptop. This
capability enables new services in the market, such as Fixed-Mobile Convergence (FMC), which integrates a fixed network (traditional
telephony, WLAN) and a mobile network (cellular) to provide seamless voice communications anytime, anywhere. These new applications
require a WLAN connection availability nearly everywhere. However, due to limited budgets, a university can only install APs
in places with a high connection demand. We propose a novel WLAN AP placement technique that takes user mobility into consideration.
This new approach is more complete than previous approaches, which mainly focus on coverage area and throughput data. Our
technique has been implemented in our university. The results show the suitability of the WLAN access point locations in our
university campus based on user mobility and activities. 相似文献