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1 – 10 of 52Wei Li, Hang Chen and Dharma P. Agrawal
In code‐division multiple‐access (CDMA) systems, the number of mobile users that each cell can support is limitedby the total received power or interference received at each base…
Abstract
In code‐division multiple‐access (CDMA) systems, the number of mobile users that each cell can support is limited by the total received power or interference received at each base station (BS) and can vary with time. The total received power can be used as an indicator of traffic load in call admission control. In this paper, we propose a call admission control (CAC) scheme based on the total received power for CDMA systems supporting integrated voice/data services. Based on the current measure of the received power, we develop an algorithm to estimate the updated total received power due to a new incoming call. We analyze the optimal admission threshold for both power limited cells and interference limited cells. We model the system by a multi‐dimensional Markov chain and compute the system performance in terms of new call blocking probability, forced termination probability of voice calls, average transmission delay of data calls and outage probability. We compare our results with an existing degradation scheme.
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Heterogeneous network is mainly focused to enrich the demands of network's traffic and data rate. Heterogeneous network is an integrated system composed of diverse radio access…
Abstract
Purpose
Heterogeneous network is mainly focused to enrich the demands of network's traffic and data rate. Heterogeneous network is an integrated system composed of diverse radio access technologies such as Wi-Fi, UMTS and WiMAX soon. To exchange the packets among these different wireless technologies, an adoptable vertical handoff (VHO) is required.
Design/methodology/approach
Various types of techniques have been proposed in line with VHO. However these algorithms lead to the threat of high dropping rate and poor Quality of Service (QoS). We modulate a new methodology by integrating Convolutional Neural Network with Fuzzy Logic (CNN-FL) for an optimum vertical handoff decision process (VHDP). The CNN-FL–based VHDP is very effective because of nonlinearity and generalization capability with uncertain data inputs.
Findings
The performance results exhibit that proposed methods show efficient for selecting the appropriate network with maximum throughput. At the same time, the proposed method reduces computational complexity and dropping rate considerably.
Originality/value
This paper proposes a novel CNN model along with a FL model for achieving a vertical hand off.
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Mithun B. Patil and Rekha Patil
Vertical handoff mechanism (VHO) becomes very popular because of the improvements in the mobility models. These developments are less to certain circumstances and thus do not…
Abstract
Purpose
Vertical handoff mechanism (VHO) becomes very popular because of the improvements in the mobility models. These developments are less to certain circumstances and thus do not provide support in generic mobility, but the vertical handover management providing in the heterogeneous wireless networks (HWNs) is crucial and challenging. Hence, this paper introduces the vertical handoff management approach based on an effective network selection scheme.
Design/methodology/approach
This paper aims to improve the working principle of previous methods and make VHO more efficient and reliable for the HWN.Initially, the handover triggering techniques is modelled for identifying an appropriate place to initiate handover based on the computed coverage area of cellular base station or wireless local area network (WLAN) access point. Then, inappropriate networks are eliminated for determining the better network to perform handover. Accordingly, a network selection approach is introduced on the basis ofthe Fractional-dolphin echolocation-based support vector neural network (Fractional-DE-based SVNN). The Fractional-DE is designed by integrating Fractional calculus (FC) in Dolphin echolocation (DE), and thereby, modifying the update rule of the DE algorithm based on the location of the solutions in past iterations. The proposed Fractional-DE algorithm is used to train Support vector neural network (SVNN) for selecting the best weights. Several parameters, like Bit error rate (BER), End to end delay (EED), jitter, packet loss, and energy consumption are considered for choosing the best network.
Findings
The performance of the proposed VHO mechanism based on Fractional-DE is evaluated based on delay, energy consumption, staytime, and throughput. The proposed Fractional-DE method achieves the minimal delay of 0.0100 sec, the minimal energy consumption of 0.348, maximal staytime of 4.373 sec, and the maximal throughput of 109.20 kbps.
Originality/value
In this paper, a network selection approach is introduced on the basis of the Fractional-Dolphin Echolocation-based Support vector neural network (Fractional-DE-based SVNN). The Fractional-DE is designed by integrating Fractional calculus (FC) in Dolphin echolocation (DE), and thereby, modifying the update rule of the DE algorithm based on the location of the solutions in past iterations. The proposed Fractional-DE algorithm is used to train SVNN for selecting the best weights. Several parameters, like Bit error rate (BER), End to end delay (EED), jitter, packet loss, and energy consumption are considered for choosing the best network.The performance of the proposed VHO mechanism based on Fractional-DE is evaluated based on delay, energy consumption, staytime, and throughput, in which the proposed method offers the best performance.
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Bernard J. Mohr, Michael J. Feinson and Nancy Shendell-Falik
The high-risk/high-stress nature of hospital emergency departments has made handoffs (i.e. patient transfers across organizational units) an area of significant safety…
Abstract
The high-risk/high-stress nature of hospital emergency departments has made handoffs (i.e. patient transfers across organizational units) an area of significant safety consequence, as evidenced by numerous studies and 2006 Comprehensive Accreditation Manual for Hospitals: The Official Handbook (CAMH). Joint Commission Resources, Inc.: Author; 2005. This same high-risk/high-stress environment is known for generating resistance to traditional deficit-based, external expert driven approaches to improvement. The authors describe how one hospital overcame this resistance by using an Appreciative Inquiry approach to the redesign of the information flow and organizational roles within a mission-critical area of the hospital. Rather than designing to ameliorate the root causes of ineffective handoffs, this positive lens approach (Appreciative Inquiry) was used to engage staff in identifying and expanding upon their most effective handoff experiences. Implications for shifting from problem-based design to a positive lens approach in the creation of micro-information systems and new organizational processes are discussed.
Danping Ren, JiJun Zhao and Jinhua Hu
User-oriented seamless service handoff is prosperous in the ubiquitous computing environment. This paper aims to present an open architecture for the user-oriented seamless…
Abstract
Purpose
User-oriented seamless service handoff is prosperous in the ubiquitous computing environment. This paper aims to present an open architecture for the user-oriented seamless service handoff across heterogeneous platforms. The migration of service environment is the key to implement the user-oriented service handoff. A distributed service handoff scheme based on the binary sensor network and context-aware middleware has been proposed.
Design/methodology/approach
To validate this scheme, a test-bed has been constructed in the lab environment.
Findings
The experimental results show that the proposed scheme can reduce the service handoff delay compared to the centralized scheme.
Originality/value
The experimental results show that the scheme can reduce the delay of service handoff compared to the traditional centralized scheme.
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Quan Le‐Trung, Paal E. Engelstad, Vinh Pham, Tor Skeie, Amirhosein Taherkordi and Frank Eliassen
The purpose of this paper is to describe the required functionalities on providing internet connectivity and mobility management for mobile ad hoc networks (MANETs), present…
Abstract
Purpose
The purpose of this paper is to describe the required functionalities on providing internet connectivity and mobility management for mobile ad hoc networks (MANETs), present discovered problems such as inconsistent contexts, and provide the corresponding solutions. It also provides a hybrid metric for the load‐balance of intra/inter‐MANET traffic over multiple internet gateways (IGWs).
Design/methodology/approach
The paper uses both mathematical analyses and simulations to discover the required functionalities and problems on providing internet connectivity and mobility management for MANETs. The proposed hybrid metric for IGW selection is a replacement of the shortest hop‐count (HC) metric, and consider three factors: HC distance, intra‐MANET traffic, and inter‐MANET traffic.
Findings
Simulation results show that ad hoc routing protocols, using the proposed metric, get better performance in terms of packet delivery ratio and transmission delay, at the cost of slightly increased signalling overhead.
Research limitations/implications
In the assessment, simulation results are taken from two mobility scenarios, and the hybrid metric is integrated into only reactive ad hoc routing. Thus, more case studies need to be carried out to demonstrate the outcomes of the proposed metric compared with others.
Practical implications
This paper provides the needed functionalities for broadening the richness of MANET applications to internet users, and vice verse.
Originality/value
This paper contributes to the research on internetworking and mobility management between MANETs and the internet.
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This research aims to examine the relationships among leadership and culture, human resources and process improvement in lean hospitals from the socio-technical perspective.
Abstract
Purpose
This research aims to examine the relationships among leadership and culture, human resources and process improvement in lean hospitals from the socio-technical perspective.
Design/methodology/approach
The survey instrument was developed from literature reviews, verified by experts and confirmatory factor analysis. Multiple responses were used to collect data from 473 care providers in 220 outpatient departments of Thai hospitals to improve reliability of the obtained data. Path analysis of structural equation modeling was applied to analyze the hypotheses.
Findings
It was found that human resources has a significant positive direct effect on process improvement. Leadership and culture not only has significant direct positive impacts on human resources and process improvement but also has a significant indirect positive impact on process improvement through human resources.
Originality/value
This is one of the first examples of research to present insights into the links between soft and hard factors of lean hospitals at strategic and operational levels.
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Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in…
Abstract
Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.
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Sam Solaimani, Jack van der Veen, Durward K. Sobek II, Erdogan Gulyaz and Venu Venugopal
Increasingly, a firm’s innovation capability has become one of the key frontiers of competitive advantage. The Lean philosophy has a well-proven reputation for its focus on…
Abstract
Purpose
Increasingly, a firm’s innovation capability has become one of the key frontiers of competitive advantage. The Lean philosophy has a well-proven reputation for its focus on process efficiency and effectiveness, and therefore, is often applied in various areas of innovation. Such wide and ever-increasing applicability also has resulted in an incoherent corpus of literature on Lean innovation. The purpose of this paper is to conceptualize an integrative view on Lean innovation management.
Design/methodology/approach
Based on a systematic literature review, the key Lean principles and practices useful in the context of innovation management are identified and synthesized into an all-inclusive framework. By means of three illustrative cases (i.e. public hospital, electronics company and avionics manufacturer), this paper elaborates on how the proposed framework can be applied.
Findings
A total of 88 publications are analyzed, leading to 34 Lean principles and practices relevant to innovation management, which are further integrated into a comprehensive model, dubbed the “Leanovation” framework.
Originality/value
This study is the first attempt to advance the understanding of various interrelated and interdependent components of Lean innovation management in a holistic way.
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