Jongtack Jung

MR-CloudSim: Designing and implementing MapReduce computing model on CloudSim

Nowadays, we can hear the word “cloud” everywhere. Cloud web storage, cloud-based web applications, and cloud networks, they all indicate that cloud has become more important than it has ever been. Internet service providers (ISP) and internet contents providers (ICP) are providing more and more services with cloud computing, and also in mobile computing environments, a cloud service is drawing much attention from the community. The biggest advantage of cloud computing is clear. As far as the user is connected to the cloud, (s)he can have all the extra computing power and storage no matter what his device is. However, empirical validation of various research projects on a cloud system seems to be ineffective in both cost and time since it requires involving to a huge amount of computing facilities and resources. Even with its importance as commerce and inconvenience of researching, there are not many simulators that can provide a simulation environment for cloud computing and datacenters. Thus, we propose a simulation tool that supports the MapReduce model, the most widely used programming model for big data processing, implemented on CloudSim, an open source simulator for cloud computing and datacenters.

AFAR: A robust and delay-constrained communication framework for smart grid applications

Abstract The existing electrical grid is now experiencing a revolutionary change to a new paradigm, i.e., smart grid, due to the development of information and communication technologies. Communications among smart grid components such as sensors, intelligent electronic devices (IED), and smart meters of automatic metering infrastructure (AMI) are some of the key components to successfully build smart grid. To reduce installation costs and spatial limits, wireless communications are considered as effective communication techniques in smart grid. However, severe wireless interference due to the electromagnetic wave generated by electronic devices, and strict requirements of smart grid applications such as delay-constraint, short delay, reliability, and scalability are making existing network protocols inappropriate for smart grid applications. In this paper, we propose AFAR to provide robust and delay-constrained communication services to smart grid applications while satisfying their requirements successfully. This paper includes a detailed description of the framework, mathematical modeling, OPNET simulation, and co-simulation between OpenDSS and OPNET to evaluate AFAR under the specific smart grid application scenario.

Poster: Asynchronous Acoustic Localization using Commercial Devices

In this paper, we design and implement an asynchronous multi-device acoustic localization system. Although the relative position and distance can be useful to many applications such as drone swarming, not much research has been conducted on the field. As synchronizing multiple devices can be difficult or even impossible with certain hardware, we devised an asynchronous algorithm that provides a high accuracy ranging and localization. A high performance ranging and localization technique that uses a relatively minor source, sound, can provide a new set of characteristics. Our proposed algorithm can work on most commercial devices that have acoustic capabilities.

Poster: A Multi-Drone Platform for Empowering Drones' Teamwork

The rapid development of UAV technology has opened up numerous applications. Further, cooperating drones\footnote{In this paper, we refer to all types of UAVs as drones.} possess a great potential in various areas of applications. Yet, there has not been a platform for a fleet of drones. It is rather difficult to control multiple drones through a single ground control station. In fact, drones need to consistently exchange flight information to maintain the formation of the fleet and follow the commands given from the GCS. Thus, drones need a robust network established among the fleet to provide a fleet control. In this paper, we propose Net-Drone, a multi-drone platform for applications that require cooperation of multiple drones. Net-Drone is equipped with strong network functionalities to provide a control system for a fleet of drones. Through case studies conducted with a prototype implementation, the proposed system is demonstrated. Video of the conducted case study can be found in http://youtu.be/lFaWsEmiQvw.

Devising Mobile Sensing and Actuation Infrastructure with Drones

Vast applications and services have been enabled as the number of mobile or sensing devices with communication capabilities has grown. However, managing the devices, integrating networks or combining services across different networks has become a new problem since each network is not directly connected via back-end core networks or servers. The issue is and has been discussed especially in wireless sensor and actuator networks (WSAN). In such systems, sensors and actuators are tightly coupled, so when an independent WSAN needs to collaborate with other networks, it is difficult to adequately combine them into an integrated infrastructure. In this paper, we propose drone-as-a-gateway (DaaG), which uses drones as mobile gateways to interconnect isolated networks or combine independent services. Our system contains features that focus on the service being provided in the order of importance, different from an adaptive simple mobile sink system or delay-tolerant system. Our simulation results have shown that the proposed system is able to activate actuators in the order of importance of the service, which uses separate sensors’ data, and it consumes almost the same time in comparison with other path-planning algorithms. Moreover, we have implemented DaaG and presented results in a field test to show that it can enable large-scale on-demand deployment of sensing and actuation infrastructure or the Internet of Things (IoT).

Link-Aware Reconfigurable Point-to-Point Video Streaming for Mobile Devices

Even though people of all social standings use current mobile devices in the wide spectrum of purpose from entertainment tools to communication means, some issues with real-time video streaming in hostile wireless environment still exist. In this article, we introduce CoSA, a link-aware real-time video streaming system for mobile devices. The proposed system utilizes a 3D camera to distinguish the region of importance (ROI) and non-ROI region within the video frame. Based on the link-state feedback from the receiver, the proposed system allocates a higher bandwidth for the region that is classified as ROI and a lower bandwidth for non-ROI in the video stream by reducing the videos bit rate. We implemented CoSA in a real test-bed where the IEEE 802.11 is employed as a medium for wireless networking. Furthermore, we verified the effectiveness of the proposed system by conducting a thorough empirical study. The results indicate that the proposed system enables real-time video streaming while maintaining a consistent visual quality by dynamically reconfiguring video coding parameters according to the link quality.

Avss: Airborne video surveillance system

Most surveillance systems only contain CCTVs. CCTVs, however, provide only limited maneuverability against dynamic targets and are inefficient for short term surveillance. Such limitations do not raise much concern in some cases, but for the scenario in which traditional surveillance systems do not suffice, adopting a fleet of UAVs can help overcoming the limitations. In this paper, we present a surveillance system implemented with a fleet of unmanned aerial vehicles (UAVs). A surveillance system implemented with a fleet of UAVs is easy to deploy and maintain. A UAV fleet requires little time to deploy and set up, and removing the surveillance is also virtually instant. The system we propose deploys UAVs to the target area for installation and perform surveillance operations. The camera mounted UAVs act as surveillance probes, the server provides overall control of the surveillance system, and the fleet platform provides fleet-wise control of the UAVs. In the proposed system, the UAVs establish a network and enable multi-hop communication, which allows the system to widen its coverage area. The operator of the system can control the fleet of UAVs via the fleet platform and receive surveillance information gathered by the UAVs. The proposed system is described in detail along with the algorithm for effective placement of the UAVs. The prototype of the system is presented, and the experiment carried out shows that the system can successfully perform surveillance over an area set by the system.

Empowering Drones’ Teamwork with Airborne Network

We propose a unified platform for multiple unmanned aerial vehicles (UAV). Recently, the UAV technology has seen a great development. However, the capability of single drone is yet limited by its physical features. To better enhance the capability of drones, we have devised and implemented a fleet based multi-UAV platform. Our proposed platform consists of powerful network functions and enhanced control and sensing algorithms, so that a unified fleet control can be accomplished. Further, it provides a platform for applications that require multiple UAVs working together. The network functions of the proposed platform achieves a strong connectivity and robustness, and a precise relative and absolute localization enables a fleet based control system. With the help of core modules, the proposed platform achieves a well controlled fleet flight and network management.

Augmenting small cell with personal area cell for performance improvement

Since mobile traffic has been increased tremendously due to popularization of high-end mobile devices, many mobile carriers and smartphone manufacturers have put their best effort on solving the capacity problem. Small cell is introduced as an idea for the solution, and various mobile carriers have installed small cells to provide more bandwidth to areas that have too much traffic to be handled by single cell tower. In this paper, we state a problem that is an extended version of current capacity problem, and argue that the problem cannot be solved by installing small cells only. Therefore, we propose the concept of Personal Area Cell (PAC) that is portable and able to perform multi-hop transmissions. In order to justify the proposed problem and solution, a traffic model is designed and simulated. The simulation results show that small cell based network is inefficient when population and traffic of each cell are changed over time while PAC adopted network is cost-efficient and adaptive to such the change.

CoSA: Adaptive link-aware real-time streaming for mobile devices

Programmable wireless devices which can perceive the current radio environment, decide available spectra, and dynamically change the radio access method, and networking protocols have been proposed to improve spectrum usage, interference mitigation, and connectivity. However, these transitions are currently lacking at upper layers. In this paper, we propose an upper layer cognitive system beyond channel sensing effectiveness and spectrum utilization achieved in adjusting PHY and MAC parameter settings. The proposed cognitive video streaming system achieves end-to-end goals at an upper video layer: quality of experience, service continuity, and survivability. Based on the link state of the receiver, the proposed system identifies areas of importance in the image stream, allocates higher bandwidth for the important areas compared to the other areas which is adjusted to use the less bandwidth with CoSA encoder and decoder, and receive the link state feedback from the receiver. To further understand the CoSAs benefit, we implemented two real test-beds for the cognitive video streaming system where the one uses conventional IEEE 802.11 networking technologies and the other employs a software defined radio platform, and performed a performance evaluation study in order to see the effectiveness of the proposed scheme. The results indicate that the proposed system can dynamically change actual data rates according to SINR feedback, which results in at least 180% improvement of transmission time compared to conventional method, while maintaining PSNR range between 30 to 40 dB with eminently reduced data size.