Division of Engineering, Business & Computing (Berks)

  • United States

Research Output 1994 2020

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Conference contribution

A clonal selection algorithm to investigate diverse solutions for the reliable server assignment problem

Konak, A. & Kulturel-Konak, S., Dec 1 2011, ECTA 2011 FCTA 2011 - Proceedings of the International Conference on Evolutionary Computation Theory and Applications and International Conference on Fuzzy Computation Theory and Applications. p. 156-161 6 p. (ECTA 2011 FCTA 2011 - Proceedings of the International Conference on Evolutionary Computation Theory and Applications and International Conference on Fuzzy Computation Theory and Applications).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Clonal Selection Algorithm
Assignment Problem
Simulation Optimization
Servers
Server

A collaborative teamwork experience between industrial engineering students of the Middle East Technical University and the Business Administration students of the Pennsylvania State University

Kulturel-Konak, S., Sayin, E. & Alpay, N., Jan 1 2005, SEFI 2005 Annual Conference: Engineering Education at the Cross-Roads of Civilizations. Middle East Technical University, Faculty of Engineering, p. 372-379 8 p. (SEFI 2005 Annual Conference: Engineering Education at the Cross-Roads of Civilizations).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

business administration
Industrial engineering
teamwork
Middle East
Students
2 Citations (Scopus)

A comparison study of the commutation methods for the three-phase permanent magnet brushless DC motor

Lee, S., Lemley, T. & Keohane, G., Dec 1 2009, Electrical Manufacturing Technical Conference 2009: Electrical Manufacturing and Coil Winding Expo. p. 49-55 7 p. (Electrical Manufacturing Technical Conference 2009: Electrical Manufacturing and Coil Winding Expo).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Brushless DC motors
Electric commutation
Permanent magnets
Torque
Feedback
7 Citations (Scopus)

Acoustic measurements using common computer accessories: Do try this at home

Litwhiler, D. H. & Lovell, T. D., 2005, 2005 ASEE Annual Conference and Exposition, Conference Proceedings. p. 127-136 10 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Accessories
Acoustics
Acoustic waves
Acoustic wave velocity
Microphones

A cyber security discovery program: Hands-on cryptography

Konak, A., Jan 1 2014, ISEC 2014 - 4th IEEE Integrated STEM Education Conference. Institute of Electrical and Electronics Engineers Inc., 6891029. (ISEC 2014 - 4th IEEE Integrated STEM Education Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

informal learning
privacy
information system
assets
student
5 Citations (Scopus)

Adaptive source localization by a mobile robot using signal power gradient in sensor networks

Sun, Y., Xiao, J., Li, X. & Cabrera-Mora, F., Dec 1 2008, 2008 IEEE Global Telecommunications Conference, GLOBECOM 2008. p. 17-21 5 p. 4697787. (GLOBECOM - IEEE Global Telecommunications Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Mobile robots
Sensor networks
Robots
Sensors
Signal to noise ratio
7 Citations (Scopus)

A distributed algorithm for mobile robot localization and mapping in wireless sensor networks

Wong, R., Hu, S., Cabrera, F., Xiao, J. & Tan, J., Oct 27 2008, Proceedings of the 2008 IEEE International Conference on Information and Automation, ICIA 2008. p. 560-566 7 p. 4608063. (Proceedings of the 2008 IEEE International Conference on Information and Automation, ICIA 2008).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Parallel algorithms
Mobile robots
Wireless sensor networks
Robots
Navigation
4 Citations (Scopus)

A distributed multi-agent algorithm for topology control in mobile ad-hoc networks

Konak, A., Aug 30 2017, 2017 18th International Conference on Advanced Robotics, ICAR 2017. Institute of Electrical and Electronics Engineers Inc., p. 244-249 6 p. 8023525. (2017 18th International Conference on Advanced Robotics, ICAR 2017).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Topology Control
Mobile ad hoc networks
Mobile Ad Hoc Networks
Topology
Flocking

A dynamic flocking algorithm with a restrictive partnership model to support mobile ad hoc networks

Konak, A. & Kulturel-Konak, S., Mar 9 2018, 2017 IEEE International Conference on Real-Time Computing and Robotics, RCAR 2017. Institute of Electrical and Electronics Engineers Inc., Vol. 2017-July. p. 593-597 5 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Flocking
Mobile ad hoc networks
Mobile Ad Hoc Networks
Model
Autonomous agents
1 Citation (Scopus)

A dynamic model-aided sensor fusion approach to aircraft attitude estimation

Rhudy, M. B., Sep 27 2017, 2017 IEEE 60th International Midwest Symposium on Circuits and Systems, MWSCAS 2017. Institute of Electrical and Electronics Engineers Inc., Vol. 2017-August. p. 1406-1409 4 p. 8053195

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Dynamic models
Fusion reactions
Aircraft
Sensors
Remote sensing

Agent-based simulations for multi-robot systems exploration of tree-like environments

Konak, A., Cabrera-Mora, F. & Kulturel-Konak, S., Jan 22 2019, 2018 IEEE International Conference on Real-Time Computing and Robotics, RCAR 2018. Institute of Electrical and Electronics Engineers Inc., p. 172-176 5 p. 8621759. (2018 IEEE International Conference on Real-Time Computing and Robotics, RCAR 2018).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Multi-robot Systems
Agent-based Simulation
Robot
Robots
Vertex of a graph
4 Citations (Scopus)

Allocation of multiple wireless access points in mobile networks

Bartolacci, M. R., Peltsverger, B., Konak, A. & Peltsverger, S., 2004, Proceedings of the 42nd Annual Southeast Regional Conference, ACM-SE 42. p. 1-4 4 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Wireless networks

A multi-year thermoelectric energy harvesting project for first-year engineering and technology students

Litwhiler, D. H., 2014, 121st ASEE Annual Conference and Exposition: 360 Degrees of Engineering Education. American Society for Engineering Education

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Energy harvesting
Students
Pipe
Water
Heat pipes
1 Citation (Scopus)

Analytical determination of trim values for nonlinear fixed wing aircraft models

Rhudy, M., Jan 1 2016, AIAA Modeling and Simulation Technologies Conference. American Institute of Aeronautics and Astronautics Inc, AIAA, AIAA 2016-4301. (AIAA Modeling and Simulation Technologies Conference, 2016).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Aircraft models
Fixed wings
Aircraft
Elevators
Angle of attack
6 Citations (Scopus)

An ant colony optimization approach to the minimum tool switching instant problem in flexible manufacturing system

Konak, A. & Kulturel-Konak, S., 2007, Proceedings of the 2007 IEEE Symposium on Computational Intelligence in Scheduling, CI-Sched 2007. p. 43-48 6 p. 4218595

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Flexible manufacturing systems
Ant colony optimization
Productivity
12 Citations (Scopus)

An effective news recommendation in social media based on users' preference

Yuan, X., Chen, Z., Changzheng, Z., Xun, L. & Qing, L., Jan 1 2008, 2008 International Workshop on Education Technology and Training and 2008 International Workshop on Geoscience and Remote Sensing, ETT and GRS 2008. IEEE Computer Society, p. 627-631 5 p. 5070235. (2008 International Workshop on Education Technology and Training and 2008 International Workshop on Geoscience and Remote Sensing, ETT and GRS 2008; vol. 1).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Feedback
Experiments
recommendation
social media
experiment

A network interdiction perspective for providing emergency communications: An analysis for promoting resiliency subject to resource constraints and security concerns

Bartolacci, M. & Dimitrov, S., Jan 1 2016, ISCRAM 2016 Conference Proceedings - 13th International Conference on Information Systems for Crisis Response and Management. Antunes, P., Banuls Silvera, V. A., Porto de Albuquerque, J., Moore, K. A. & Tapia, A. H. (eds.). Information Systems for Crisis Response and Management, ISCRAM, (Proceedings of the International ISCRAM Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Communication
Disasters
Telecommunication networks
Resource constraints
Resiliency
6 Citations (Scopus)

An exploratory factor analysis of student learning in a collaborative virtual computer laboratory

Konak, A., Bartolacci, M. R. & Huff, H. M., 2012, 18th Americas Conference on Information Systems 2012, AMCIS 2012. Vol. 5. p. 3557-3564 8 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Factor analysis
Security of data
factor analysis
Students
learning

Ant colony optimization for the unequal-area facility layout problem

Kulturel-Konak, S. & Konak, A., Dec 1 2011, ECTA 2011 FCTA 2011 - Proceedings of the International Conference on Evolutionary Computation Theory and Applications and International Conference on Fuzzy Computation Theory and Applications. p. 273-277 5 p. (ECTA 2011 FCTA 2011 - Proceedings of the International Conference on Evolutionary Computation Theory and Applications and International Conference on Fuzzy Computation Theory and Applications).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Facility Layout
Ant colony optimization
Unequal
Flexible Structure
Flexible structures
1 Citation (Scopus)

Anything is possible - Teaching Entrepreneurship in an interactive K-12 workshop

Cioffi, N., Kulturel-Konak, S. & Konak, A., Jan 1 2014, ISEC 2014 - 4th IEEE Integrated STEM Education Conference. Institute of Electrical and Electronics Engineers Inc., 6891013. (ISEC 2014 - 4th IEEE Integrated STEM Education Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

entrepreneurship
Teaching
student
school
self-efficacy

A portable base station optimization model for wireless infrastructure deployment in disaster planning and management

Bartolacci, M. R., Aubrecht, C. & Aubrecht, D. O., Jan 1 2014, ISCRAM 2014 Conference Proceedings - 11th International Conference on Information Systems for Crisis Response and Management. The Pennsylvania State University, p. 55-59 5 p. (ISCRAM 2014 Conference Proceedings - 11th International Conference on Information Systems for Crisis Response and Management).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Base stations
Disasters
Wireless networks
Planning
Communication

A research on the sequential pattern similarity of time series

Lin, X., Zhou, Y. & Xue, Y., Nov 5 2009, Proceedings - 2009 International Forum on Information Technology and Applications, IFITA 2009. p. 247-250 4 p. 5231213. (Proceedings - 2009 International Forum on Information Technology and Applications, IFITA 2009; vol. 2).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Time series
Experiments
9 Citations (Scopus)

Assessing professional skills in STEM disciplines

Kulturel-Konak, S., Konak, A., Esparragoza, I. E. & Kremer, G. E. O., Jul 15 2013, ISEC 2013 - 3rd IEEE Integrated STEM Education Conference. 6525216. (ISEC 2013 - 3rd IEEE Integrated STEM Education Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Students
Curricula
Communication
STEM (science, technology, engineering and mathematics)
1 Citation (Scopus)

Assessing students' global awareness

Chipperfield, S., Kulturel-Konak, S. & Konak, A., Jun 8 2015, ISEC 2015 - 5th IEEE Integrated STEM Education Conference. Institute of Electrical and Electronics Engineers Inc., p. 151-152 2 p. 7119912

Research output: Chapter in Book/Report/Conference proceedingConference contribution

student
learning
mathematics
engineering
research focus
2 Citations (Scopus)

Assessing teamwork skills and knowledge

Vance, K., Kulturel-Konak, S. & Konak, A., Jan 1 2014, ISEC 2014 - 4th IEEE Integrated STEM Education Conference. Institute of Electrical and Electronics Engineers Inc., 6891052. (ISEC 2014 - 4th IEEE Integrated STEM Education Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

teamwork
learning
mathematics
engineering
educational setting

A study on meta pattern similarity of time series

Lin, X., Li, Z., Zhou, Y. & Xue, Y., Dec 1 2010, Proceedings - 2010 International Forum on Information Technology and Applications, IFITA 2010. p. 121-124 4 p. 5635166. (Proceedings - 2010 International Forum on Information Technology and Applications, IFITA 2010; vol. 1).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Time series
Meteorology
Distance measurement
Finance

A tool for assessing ethical awareness and reasoning development of engineering students

Esparragoza, I. E., Kulturel-Konak, S., Konak, A. & Kremer, G. E., Jan 1 2015, Proceedings of 2014 International Conference on Interactive Collaborative Learning, ICL 2014. Institute of Electrical and Electronics Engineers Inc., p. 767-770 4 p. 7017869

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Students
engineering
student
moral philosophy
interpretation
2 Citations (Scopus)

A two semester, multi-approach instrumentation project for mechanical engineering students

Litwhiler, D. H., 2015, 122nd ASEE Annual Conference and Exposition: Making Value for Society. American Society for Engineering Education

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Mechanical engineering
Students
Microcontrollers
Pressure transducers
Calibration

A "Virtual SONET" routing architecture for ad hoc networks in environmental monitoring and emergency management

Bartolacci, M. R. & Avery-Gomez, E., Dec 1 2011, 2011 Wireless Telecommunications Symposium, WTS 2011. 5960891

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Ad hoc networks
Disasters
Monitoring
Fault tolerance
Sensor networks
2 Citations (Scopus)

Behaviorally anchored rating scales for teamwork peer assessment

Konak, A., Magluilo, S. & Kulturel-Konak, S., Apr 20 2016, ISEC 2016 - Proceedings of the 6th IEEE Integrated STEM Education Conference. Institute of Electrical and Electronics Engineers Inc., p. 168-172 5 p. 7457525. (ISEC 2016 - Proceedings of the 6th IEEE Integrated STEM Education Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Team Work
teamwork
rating scale
Students
Evaluation
4 Citations (Scopus)

Best practices to design hands-on activities for virtual computer laboratories

Konak, A., Clark, T. & Nasereddin, M., Jul 18 2013, ISEC 2013 - 3rd IEEE Integrated STEM Education Conference. 6525215. (ISEC 2013 - 3rd IEEE Integrated STEM Education Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Security of data
Students
Information technology
1 Citation (Scopus)

By when do you need this done? Discovering knowledge workers' time management practices

Wu, D., Passerini, K. & Bartolacci, M. R., Dec 1 2008, 14th Americas Conference on Information Systems, AMCIS 2008. p. 1653-1659 7 p. (14th Americas Conference on Information Systems, AMCIS 2008; vol. 3).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

time management
worker
Taxonomies
Knowledge management
knowledge management
16 Citations (Scopus)

Choosing IT as a career: Exploring the role of self-efficacy and perceived importance of IT skills

Joshi, K. D., Kvasny, L., McPherson, S., Trauth, E., Kulturel-Konak, S. & Mahar, J., Dec 1 2010, ICIS 2010 Proceedings - Thirty First International Conference on Information Systems. (ICIS 2010 Proceedings - Thirty First International Conference on Information Systems).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Students
Education
7 Citations (Scopus)

Combining network reductions and simulation to estimate network reliability

Konak, A., Dec 1 2007, Proceedings of the 2007 Winter Simulation Conference, WSC. p. 2301-2305 5 p. 4419868. (Proceedings - Winter Simulation Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Network Reliability
Estimate
Simulation
Exact Computation
Variance Reduction
6 Citations (Scopus)

Control performance analysis for autonomous close formation flight experiments

Rice, C., Gu, Y., Chao, H., Larrabee, T., Gururajan, S., Napolitano, M., Mandal, T. & Rhudy, M. B., Jan 1 2014, 2014 International Conference on Unmanned Aircraft Systems, ICUAS 2014 - Conference Proceedings. IEEE Computer Society, p. 1175-1180 6 p. 6842372. (2014 International Conference on Unmanned Aircraft Systems, ICUAS 2014 - Conference Proceedings).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Research aircraft
Gas emissions
Greenhouse gases
Controllers
Testing
3 Citations (Scopus)

Creative problem solving builds entrepreneurial mindset

Camacho, A. P., Janowski, A., Konak, A. & Kulturel-Konak, S., Apr 20 2016, ISEC 2016 - Proceedings of the 6th IEEE Integrated STEM Education Conference. Institute of Electrical and Electronics Engineers Inc., p. 65-70 6 p. 7457556

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Technical presentations
Students
creativity
student
Nicaragua
4 Citations (Scopus)

Crisis management and mobile devices: Extending the usage of sensor networks within an integrated system framework

Gomez, E. A. & Bartolacci, M. R., Jan 1 2011, 8th International Conference on Information Systems for Crisis Response and Management: From Early-Warning Systems to Preparedness and Training, ISCRAM 2011. Information Systems for Crisis Response and Management, ISCRAM, (8th International Conference on Information Systems for Crisis Response and Management: From Early-Warning Systems to Preparedness and Training, ISCRAM 2011).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Mobile devices
Sensor networks
Information dissemination
Military applications
Sensors
5 Citations (Scopus)

Decentralized energy-based hybrid control for the multi-RTAC system

Avis, J. M., Nersesov, S. G. & Nathan, R., Nov 23 2009, 2009 American Control Conference, ACC 2009. p. 895-900 6 p. 5159984. (Proceedings of the American Control Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Testbeds
Dynamical systems
Actuators
Electron energy levels
Computer hardware
10 Citations (Scopus)

Designing resilient networks using a hybrid genetic algorithm approach

Konak, A. & Smith, A. E., Dec 1 2005, GECCO 2005 - Genetic and Evolutionary Computation Conference. Beyer, H. G., O'Reilly, U. M., Arnold, D., Banzhaf, W., Blum, C., Bonabeau, E. W., Cantu-Paz, E., Dasgupta, D., Deb, K. & et al, A. (eds.). p. 1279-1285 7 p. (GECCO 2005 - Genetic and Evolutionary Computation Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Genetic algorithms
HIgh speed networks
Computational complexity
Topology
Communication
3 Citations (Scopus)

Determination of pruned pareto sets for the multi-objective system redundancy allocation problem

Kulturel-Konak, S. & Coit, D. W., Sep 25 2007, Proceedings of the 2007 IEEE Symposium on Computational Intelligence in Multicriteria Decision Making, MCDM 2007. p. 390-394 5 p. 4223033. (Proceedings of the 2007 IEEE Symposium on Computational Intelligence in Multicriteria Decision Making, MCDM 2007).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Redundancy
Tabu search
Monte Carlo simulation

Development and analysis of an input power factor corrected variable speed motor drive system

Lee, S., Dec 1 2013, Electrical Manufacturing and Coil Winding Expo 2010-2013. p. 76-86 11 p. (Electrical Manufacturing and Coil Winding Expo 2010-2013).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Networks (circuits)
Induction motors
Harmonic distortion
Power quality
Contamination
1 Citation (Scopus)

Development of a GPS/INS sensor fusion simulation environment using flight data

Barchesky, F. J., Gross, J. N., Gu, Y., Rhudy, M. B. & Napolitano, M. R., Dec 1 2011, AIAA Modeling and Simulation Technologies Conference 2011. p. 312-319 8 p. (AIAA Modeling and Simulation Technologies Conference 2011).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Sensor Fusion
Simulation Environment
Global positioning system
Fusion reactions
Sensors

Development of a software configurable digital controller for the three-phase PMBDCM

Lee, S., Lemley, T. & Keohane, G., Dec 1 2008, Electrical Manufacturing Technical Conference 2008. p. 97-102 6 p. (Electrical Manufacturing Technical Conference 2008).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Servo amplifiers
Permanent magnets
Controllers
Electric actuators
Polarization mode dispersion
1 Citation (Scopus)

Does the unscented Kalman filter converge faster than the extended Kalman filter? A counter example

Rhudy, M., Gu, Y. & Napolitano, M. R., Sep 16 2013, AIAA Guidance, Navigation, and Control (GNC) Conference. (AIAA Guidance, Navigation, and Control (GNC) Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Extended Kalman filters
Kalman filters
1 Citation (Scopus)

Effective assessment of mobile communication networks performance with clustering and neural modeling

Lokshina, I. & Bartolacci, M., Sep 12 2008, 7th Annual Wireless Telecommunications Symposium, WTS 2008. p. 9-16 8 p. 4547537. (7th Annual Wireless Telecommunications Symposium, WTS 2008).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Blocking probability
Automatic teller machines
Network performance
Telecommunication networks
Throughput
18 Citations (Scopus)

Effect of power factor correction circuit on switched reluctance motor drives for appliances

Krishnan, R. & Lee, S., Jan 1 1994, Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC. Anon (ed.). Publ by IEEE, Vol. 1. p. 83-89 7 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Reluctance motors
Networks (circuits)
Variable speed drives
Pollution
Switches

Effects of communication on mobile sensor networks

Cabrera, F., Xiao, J. & Sun, Y., Dec 1 2006, 2006 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2006. p. 1452-1457 6 p. 4058576. (IEEE International Conference on Intelligent Robots and Systems).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Sensor networks
Wireless networks
Communication
Ad hoc networks
7 Citations (Scopus)

Energy-based hybrid control for the RTAC system: Experimental results

Avis, J. M., Nersesov, S. G. & Nathan, R., Sep 30 2008, 2008 American Control Conference, ACC. p. 3331-3336 6 p. 4587006

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Actuators
Controllers
Closed loop systems
Electron energy levels
Energy dissipation
1 Citation (Scopus)

Engineering Education in China - A summary of a focused visit in 2010

Mott, R. L. & Speicher, T. L., 2011, 118th ASEE Annual Conference and Exposition.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Engineering education
Education
Students
17 Citations (Scopus)

Estimating path loss in wireless local area networks using ordinary kriging

Konak, A., Dec 1 2010, Proceedings of the 2010 Winter Simulation Conference, WSC'10. p. 2888-2896 9 p. 5678983. (Proceedings - Winter Simulation Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Ordinary Kriging
Wireless Local Area Network (WLAN)
Path Loss
Wireless local area networks (WLAN)
Distance Measure