WBAN MAC Protocols― Non-Saturation Modeling and Performance Analysis

( Pervez Khan ),( Niamat Ullah ),( Hoon Kim ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3

The current literature on discrete-time Markov chain (DTMC) based analysis of IEEE 802.15.6 MAC protocols for wireless body area networks (WBANs), do not consider the ACK timeout state, wherein the colliding nodes check the ill fate of their transmissions, while other contending nodes perform backoff check that slot as usual. In this paper, our DTMC model accurately captures the carrier sense multiple access with collision avoidance (CSMA/CA) mechanism of IEEE 802.15.6 medium access control (MAC) and allows the contending nodes performing backoff to utilize the ACK timeout slot during collisions. The compared rigorous results are obtained by considering a non-ideal channel in non-saturation conditions, and CSMA/CA parameters pertaining to UWB PHY of IEEE 802.15.6 MAC protocols.

Performance Analysis of WBAN MAC Protocol under Different Access Periods

Khan, Pervez,Ullah, Niamat,Alam, Md. Nasre,Kwak, Kyung Sup SAGE Publications 2015 International journal of distributed sensor networ Vol.2015 No.-

<P>The IEEE 802.15.6 is a new standard on wireless body area network (WBAN) for short-range, extremely low power wireless communication with high data rates in the vicinity of, or inside, a human body. The standard defines two contention-based channel access schemes: slotted ALOHA and carrier sense multiple access with collision avoidance (CSMA/CA) using an alternative binary exponential backoff procedure. The standard supports quality of service (QoS) differentiation through user priorities and access phases. In this study, we develop an analytical model for the estimation of performance metrics such as energy consumption, normalized throughput, and mean frame service time, employing a Markov chain model under nonsaturated heterogeneous traffic scenarios including different access phases specified in the standard for different user priorities and access methods. We conclude that the deployment of exclusive access phase (EAP) is not necessary in a typical WBAN using CSMA/CA because it degrades the overall system throughput, consumes more energy per packet, and results in higher delay for nonemergency nodes.</P>

WBAN MAC Protocols- Non-Saturation Modeling and Performance Analysis

Khan, Pervez,Ullah, Niamat,Kim, Hoon Korean Society for Internet Information 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3

The current literature on discrete-time Markov chain (DTMC) based analysis of IEEE 802.15.6 MAC protocols for wireless body area networks (WBANs), do not consider the ACK timeout state, wherein the colliding nodes check the ill fate of their transmissions, while other contending nodes perform backoff check that slot as usual. In this paper, our DTMC model accurately captures the carrier sense multiple access with collision avoidance (CSMA/CA) mechanism of IEEE 802.15.6 medium access control (MAC) and allows the contending nodes performing backoff to utilize the ACK timeout slot during collisions. The compared rigorous results are obtained by considering a non-ideal channel in non-saturation conditions, and CSMA/CA parameters pertaining to UWB PHY of IEEE 802.15.6 MAC protocols.

Seamless Interworking Architecture for WBAN in Heterogeneous Wireless Networks with QoS Guarantees

Khan, Pervez,Ullah, Niamat,Ullah, Sana,Kwak, Kyung Sup Springer-Verlag 2011 Journal of medical systems Vol.35 No.5

Role of Cardiac MRI in Complicated Cardiac Defects

Khan Yasir,Pervez Mohammad Bin,Fatimi Saulat 아시아심장혈관영상의학회 2019 Cardiovascular Imaging Asia Vol.3 No.3

Sinus of Valsalva rupture is a rare condition that results in aortocardiac shunt. Although the investigation of choice is transthoracic echocardiography, the gold standard is cardiac catheterization. We present a case of a young male with acute onset heart failure. Acute coronary syndrome blood workup was unremarkable. Transthoracic and transesophageal echocardiography revealed mild right atrial dilation with a Gerbode shunt. Right heart catheterization showed left to right shunt suggestive of acquired acute onset shunting. Eventually, a cardiac MRI revealed a ruptured sinus of Valsalva opening into the right atrium as the cause. The patient was taken to the operation theater where an aortobicaval bypass was established. A horizontal aortotomy revealed a sinus of Valsalva aneurysm arising from the right coronary sinus which was repaired using a Dacron patch. Postoperative transthoracic echocardiography showed no defect. In summary, cardiac MRI is an excellent tool for establishing a definite diagnosis for complicated cardiac defects.

RELATIVE RECIPROCAL VARIATIONAL INEQUALITIES

Khan, Awais Gul,Noor, Muhammad Aslam,Pervez, Amjad,Noor, Khalida Inayat The Honam Mathematical Society 2018 호남수학학술지 Vol.40 No.3

In this paper, we introduce a new class of reciprocal convex set which is called as relative reciprocal convex set. We establish a necessary and sufficient condition for the minimum of the differentiable relative reciprocal convex function. This condition can be viewed as a new class of variational inequality which is called relative reciprocal variational inequality. Using the auxiliary principle technique we discuss the existence criteria for the solution of relative reciprocal variational inequality. Some special cases which are naturally included in our main results are also discussed.

MIXED QUASI VARIATIONAL INEQUALITIES INVOLVING FOUR NONLINEAR OPERATORS

( Amjad Pervez ),( Awais Gul Khan ),( Muhammad Aslam Noor ),( Khalida Inayat Noor ) 호남수학회 2020 호남수학학술지 Vol.42 No.1

In this paper we introduce and consider a new class of variational inequalities with four operators. This class is called the extended general mixed quasi variational inequality. We show that the extended general mixed quasi variational inequality is equivalent to the mixed point problem. We use this alternative equivalent formulation to discuss the existence of a solution of extended general mixed quasi variational inequality and also develop several iterative methods for solving extended general mixed quasi variational inequality and its variant forms. We consider the convergence analysis of the proposed iterative methods under appropriate conditions. We also introduce a new class of resolvent equation, which is called the extended general implicit resolvent equation and establish an equivalent relation between the extended general implicit resolvent equation and the extended general mixed quasi variational inequality. Some special cases are also discussed.

RELATIVE RECIPROCAL VARIATIONAL INEQUALITIES

( Awais Gul Khan ),( Muhammad Aslam Noor Amjad Pervez ),( Khalida Inayat Noor ) 호남수학회 2018 호남수학학술지 Vol.40 No.3

In this paper, we introduce a new class of reciprocal convex set which is called as relative reciprocal convex set. We establish a necessary and sufficient condition for the minimum of the differentiable relative reciprocal convex function. This condi-tion can be viewed as a new class of variational inequality which is called relative reciprocal variational inequality. Using the auxiliary principle technique we discuss the existence criteria for the solu-tion of relative reciprocal variational inequality. Some special cases which are naturally included in our main results are also discussed.

Mapping evolution of dynamic web ontologies

Khattak, A.M.,Pervez, Z.,Khan, W.A.,Khan, A.M.,Latif, K.,Lee, S.Y. Elsevier science 2015 Information sciences Vol.303 No.-

Information on the web and web services that are revised by stakeholders is growing incredibly. The presentation of this information has shifted from a representational model of web information with loosely clustered terminology to semi-formal terminology and even to formal ontology. Mediation (i.e., mapping) is required for systems and services to share information. Mappings are established between ontologies in order to resolve terminological and conceptual incompatibilities. Due to new discoveries in the field of information sharing, the body of knowledge has become more structured and refined. The domain ontologies that represent bodies of knowledge need to be able to accommodate new information. This allows for the ontology to evolve from one consistent state to another. Changes in resources cause existing mappings between ontologies to be unreliable and stale. This highlights the need for mapping evolution (regeneration) as it would eliminate the discrepancies from the existing mappings. In order to re-establish the mappings between dynamic ontologies, the existing systems require a complete mapping process to be restructured, and this process is time consuming. This paper proposes a mapping reconciliation approach between the updated ontologies that has been found to take less time to process compared to the time of existing systems when only the changed resources are considered and also eliminates the staleness of the existing mappings. The proposed approach employs the change history of ontology in order to store the ontology change information, which helps to drastically reduce the reconciliation time of the mappings between dynamic ontologies. A comprehensive evaluation of the performance of the proposed system on standard data sets has been conducted. The experimental results of the proposed system in comparison with six existing mapping systems are provided in this paper using 13 different data sets, which support our claims.

Modeling Slotted Aloha of WBAN in Non-Saturated Conditions

( Mohammad Sanaullah Chowdhury ),( Pervez Khan ),( Jaijin Jung ),( Kyung Sup Kwak ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.6

The IEEE 802.15.6 is a communication standard for Wireless Body Area Networks (WBANs). This standard includes a prioritized slotted Aloha as a choice for medium access control. This protocol is different from the traditional version as it has integral considerations for certain priorities of users. It attempts to resolve collision by halving the probability of retransmission, lower bounded by to a minimum, in the alternate slots to follow. In this paper, we present an analytical model to compute the non-saturated throughput of this protocol in the presence of finite number of nodes. The model is validated against simulation.