Joint Optimization of Mobile Charging and Data Gathering for Wireless Rechargeable Sensor Networks

( Xianzhong Tian ),( Jiacun He ),( Yuzhe Chen ),( Yanjun Li ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.7

Recent advances in radio frequency (RF) power transfer provide a promising technology to power sensor nodes. Adoption of mobile chargers to replenish the nodes’ energy has recently attracted a lot of attention and the mobility assisted energy replenishment provides predictable and sustained power service. In this paper, we study the joint optimization of mobile charging and data gathering in sensor networks. A wireless multi-functional vehicle (WMV) is employed and periodically moves along specified trajectories, charge the sensors and gather the sensed data via one-hop communication. The objective of this paper is to maximize the uplink throughput by optimally allocating the time for the downlink wireless energy transfer by the WMV and the uplink transmissions of different sensors. We consider two scenarios where the WMV moves in a straight line and around a circle. By time discretization, the optimization problem is formulated as a 0-1 programming problem. We obtain the upper and lower bounds of the problem by converting the original 0-1 programming problem into a linear programming problem and then obtain the optimal solution by using branch and bound algorithm. We further prove that the network throughput is independent of the WMV’s velocity under certain conditions. Performance of our proposed algorithm is evaluated through extensive simulations. The results validate the correctness of our proposed theorems and demonstrate that our algorithm outperforms two baseline algorithms in achieved throughput under different settings.

센싱 데이터 수집을 위한 웹 기반의 플랫폼 설계

김유두(Yu-Doo Kim) 한국정보통신학회 2021 한국정보통신학회 종합학술대회 논문집 Vol.25 No.1

다양한 센서에서 발생하는 데이터를 효과적으로 수집하기 위해서는 각 센서에서의 임베디드된 플랫폼을 활용하는 방법이 가장 대표적이다. 하지만 임베디드된 플랫폼은 다양한 종류의 센서마다 모두 구현이 다르게 되어있어 한번에 적용하기 어렵게 되어있다. 이에 본 논문에서는 다양한 센싱 데이터를 하나의 플랫폼에서 쉽게 수집하고 관리할 수 있는 웹 기반의 데이터 수집 플랫폼을 제안하고자 한다. It is representative that utilize the platform embedded by each sensor for gathering data from sensor. However, various platforms have different implementations for different types of sensors, making it difficult to apply them at once. Therefore, in this paper, we propose a web-based data collection platform that can easily gathering and managing various sensing data on one platform.

An intelligent agent-based routing structure for mobile sinks in WSNs

Jae-Wan Kim,Jeong-Sik In,Kyeong Hur,Jin-Woo Kim,Doo-Seop Eom IEEE 2010 IEEE TRANSACTIONS ON CONSUMER ELECTRONICS - Vol.56 No.4

<P>Mobile sink brings new challenges to densely deployed and large wireless sensor networks (WSNs). When the sink moves, frequent location updates from the sink can generate excessive power consumption of sensors. In this paper, we propose IAR, an Intelligent Agent-based Routing protocol that provides efficient data delivery to mobile sink. Proposed algorithm reduces signal overhead and improve degraded route called triangular routing problem. We have evaluated IAR performance through both mathematical analysis and simulation experiments. The results show that our scheme effectively supports sink mobility with low overhead and the improvement of triangular routing problem.</P>

A Reporting Interval Adaptive, Sensor Control Platform for Energy-saving Data Gathering in Wireless Sensor Networks

( Wook Choi ),( Yong Lee ),( Sangchul Kim ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.2

Due to the application-specific nature of wireless sensor networks, the sensitivity to such a requirement as data reporting interval varies according to the type of application. Such considerations require an application-specific, parameter tuning paradigm allowing us to maximize energy conservation prolonging the operational network lifetime. In this paper, we propose a reporting interval adaptive, sensor control platform for energy-saving data gathering in wireless sensor networks. The ultimate goal is to extend the network lifetime by providing sensors with high adaptability to application-dependent or time-varying, reporting interval requirements. The proposed sensor control platform is based upon a two phase clustering (TPC) scheme which constructs two types of links within each cluster - namely, direct link and relay link. The direct links are used for control and time-critical, sensed data forwarding while the relay links are used only for multi-hop data reporting. Sensors opportunistically use the energy-saving relay link depending on the user reporting, interval constraint. We present factors that should be considered in deciding the total number of relay links and how sensors are scheduled for sensed data forwarding within a cluster for a given reporting interval and link quality. Simulation and implementation studies demonstrate that the proposed sensor control platform can help individual sensors save a significant amount of energy in reporting data, particularly in dense sensor networks. Such saving can be realized by the adaptability of the sensor to the reporting interval requirements.

스마트 양식장 수조 내 용존 산소 및 온도 제어를 위한 시스템 구현

전주현,이윤호,이나은,주문갑 대한임베디드공학회 2021 대한임베디드공학회논문지 Vol.16 No.6

Dissolved oxygen, pH, and temperature are the most important factors for fish farming because they affect fish growth and mass mortality of the fish. Therefore, fish farm workers must always check all pools on the farm, but this is very difficult in reality. That’s why we developed a control system for smart fish farms. This system includes a gateway, sensor gatherers, and a PC program using LabVIEW. One sensor gatherer can cover up to four pools. The sensor gatherers are connected to the gateway in the form of a bus. For the gateway, the ATmega2560 is used as the main processor for communication and the STM32F429 is used as a sub-processor for displaying LCD. For the sensor gatherer, ATmega2560 is used as the main processor for communication. MQTT (Message Queuing Telemetry Transport), RS-485, and Zigbee are used as the communication protocols in the control system. The users can control the temperature and the dissolved oxygen using the PC program. The commands are transferred from the PC program to the gateway through the MQTT protocol. When the gateway gets the commands, it transfers the commands to the appropriate sensor gatherer through RS-485 and Zigbee. Dissolved oxygen, pH, and temperature are the most important factors for fish farming because they affect fish growth and mass mortality of the fish. Therefore, fish farm workers must always check all pools on the farm, but this is very difficult in reality. That’s why we developed a control system for smart fish farms. This system includes a gateway, sensor gatherers, and a PC program using LabVIEW. One sensor gatherer can cover up to four pools. The sensor gatherers are connected to the gateway in the form of a bus. For the gateway, the ATmega2560 is used as the main processor for communication and the STM32F429 is used as a sub-processor for displaying LCD. For the sensor gatherer, ATmega2560 is used as the main processor for communication. MQTT (Message Queuing Telemetry Transport), RS-485, and Zigbee are used as the communication protocols in the control system. The users can control the temperature and the dissolved oxygen using the PC program. The commands are transferred from the PC program to the gateway through the MQTT protocol. When the gateway gets the commands, it transfers the commands to the appropriate sensor gatherer through RS-485 and Zigbee.

센서 네트워크에서 에너지 효율과 충돌 회피를 위한 타임 트리 스케쥴링

이길흥 한국멀티미디어학회 2009 멀티미디어학회논문지 Vol.12 No.7

This paper presents a data gathering and scheduling scheme for wireless sensor networks. We use a data gathering tree for sending the data from the sensor node to the base station. For an energy efficient operation of the sensor networks in a distributed manner, a time tree is built in order to reduce the collision probability and to minimize the total energy required to send data to the base station. A time tree is a data gathering tree where the base station is the root and each sensor node is either a relaying or a leaf node of the tree. Each tree operates in a different time schedule with possible different activation rate. Through the simulation, we found that the proposed scheme that uses time trees shows better characteristics in energy and data arrival rate when compared with other schemes such as SMAC and DMAC. 본 논문은 무선 센서 네트워크에서 데이터를 수집하고 스케쥴링을 수행하는 방안을 제시한다. 각각의 센서 노드에서 베이스 노드로 데이터를 모으기 위해, 데이터 수집 타임 트리를 사용한다. 데이터를 베이스 노드로 전송하는 과정에서 충돌 확률을 줄이고 효율적인 에너지의 사용을 위해 타임 트리가 사용된다. 타임 트리는 베이스 노드가 루트이고, 각 센서 노드가 데이터를 전송하는 중계 노드 혹은 단말 노드가 된다. 트리내의 노드는 정해진 시간에 활성화하여 데이터를 보내고, 대기상태로 돌아가 에너지를 보존한다. 각각의 타임 트리는 서로 다른 활성 비율과 활성 시간을 갖는다. 제안 기법은 SMAC과 DMAC과 같은 다른 활성 기반의 매체 접근 프로토콜과 비교해서 더 좋은 에너지 효율과 데이터 도착율을 갖는다.

이동 단말기를 위한 Three-Tier 상황정보 수집 기법

소수환(Su-Hwan Sho),김승훈(Seung-Hoon Kim) 한국산업정보학회 2009 한국산업정보학회논문지 Vol.14 No.1

기존의 센서네트워크의 연구는 센서에서 센싱된 데이터가 무선 센서네트워크를 통해서 효율적으로 정지싱크노드로 전달되는 연구가 주를 이루었다. 최근 이동성을 갖는 싱크노드의 연구가 활발히 진행되고 있지만 정지 싱크노드와 이동 싱크노드가 혼재하는 환경에 대한 연구는 미비한 실정이다. 본 논문에서는 기 구축된 클러스터 기반 다중홉 센서네트워크 환경에서 이동싱크들이 정지 싱크를 이용하여 데이터 수집이 가능한 기법을 제안한다. 이를 위해서 이동싱크들이 기존에 구축되어진 센서네트워크의 정지싱크를 중심으로 클러스터링 되고 해당 정지 싱크를 이용하여 상황정보 수집이 가능하도록 하였다. 기존에 모바일 싱크를 위해 제안되었던 TTDD 라우팅 프로토콜과 비교하여 수학적 분석을 통해, 이동싱크의 수가 많아지거나 이동싱크의 이동횟수가 많아 질수록 더 우수한 성능을 보임을 확인하였다. Previous research on sensor networks mainly focused on efficient transmission of data from sensors to fixed sink nodes. Recently there has been active research on mobile sink nodes, but the re-search of an environment where both fixed sink nodes and mobile sinks are present at the same time is rather scarce. This paper proposes a technique for context gathering by mobile devices with the sink functionality added through fixed sinks under a previously built, cluster based multi hop sensor network environment. To this end, clustering of mobile devices were done based on the fixed sinks of a previously built sensor network, and by using appropriate fixed sinks, context gathering was made possible, By mathematical comparison with TTDD routing protocol, which was proposed for mobile sinks, it was confirmed that performance increases in energy with the number of mobile sinks, and with the number of movements by mobile devices.

Efficient Context-Aware Scheme for Sensor Network in Ubiquitous Devices

Shim, Jong-Ik,Sho, Su-Hwan Korea Multimedia Society 2009 멀티미디어학회논문지 Vol.12 No.12

Many sensor network applications have been developed for smart home, disaster management, and a wide range of other applications. These applications, however, generally assume a fixed base station as well as fixed sensor nodes. Previous research on sensor networks mainly focused on efficient transmission of data from sensors to fixed sink nodes. Recently there has been active research on mobile sink nodes, sink mobility is one of the most comprehensive trends for information gathering in sensor networks, but the research of an environment where both fixed sink nodes and mobile sinks are present at the same time is rather scarce. This paper proposes a scheme for context-aware by ubiquitous devices with the sink functionality added through fixed sinks under a previously-built, cluster-based multi-hop sensor network environment. To this end, clustering of mobile devices were done based on the fixed sinks of a previously-built sensor network, and by using appropriate fixed sinks, context gathering was made possible. By mathematical comparison with TTDD routing protocol, which was proposed for mobile sinks, it was confirmed that performance increases by average 50% in energy with the number of mobile sinks, and with the number of movements by mobile devices.

Efficient Context-Aware Scheme for Sensor Network in Ubiquitous Devices

심종익,소수환 한국멀티미디어학회 2009 멀티미디어학회논문지 Vol.12 No.12

Many sensor network applications have been developed for smart home, disaster management, and a wide range of other applications. These applications, however, generally assume a fixed base station as well as fixed sensor nodes. Previous research on sensor networks mainly focused on efficient transmission of data from sensors to fixed sink nodes. Recently there has been active research on mobile sink nodes, sink mobility is one of the most comprehensive trends for information gathering in sensor networks, but the research of an environment where both fixed sink nodes and mobile sinks are present at the same time is rather scarce. This paper proposes a scheme for context-aware by ubiquitous devices with the sink functionality added through fixed sinks under a previously-built, cluster-based multi-hop sensor network environment. To this end, clustering of mobile devices were done based on the fixed sinks of a previously-built sensor network, and by using appropriate fixed sinks, context gathering was made possible. By mathematical comparison with TTDD routing protocol, which was proposed for mobile sinks, it was confirmed that performance increases by average 50% in energy with the number of mobile sinks, and with the number of movements by mobile devices.

무선 센서 네트워크에서 네트워크 수명 향상을 위한 체인 기반의 라우팅 모델

신병무,김진술 사단법인 미래융합기술연구학회 2020 아시아태평양융합연구교류논문지 Vol.6 No.11

The basic premise of the Internet of Things is that smart sensors collaborate directly to provide new applications. In wireless sensor networks which is another foundational technology of the Internet of Things, interconnected intelligent wireless sensors sense the surroundings, collect data and transmit it to a sink. Since many applications in wireless sensor networks depend on the battery and it is difficult to charge the battery, it is very important to establish an energy efficient path to transmit the collected data to the sink. Therefore, the research to improve the network lifetime is one of important challenges in wireless sensor networks. In this paper, we propose a chain-based routing model for improving energy efficiency and network lifetime by reducing the long-distance data transmission of some nodes in wireless sensor networks. We compare the network life our proposed routing model with PEGASIS and CSS through simulations. The proposed routing model is better in terms of performance than PEGASIS and CCS. 사물 인터넷의 기본적인 전제는 스마트 센서가 직접 협업하여 새로운 응용프로그램을 제공하는 것이다. 사물 인터넷의 또 다른 기본 기술인 무선 센서 네트워크에서 상호 연결된 다수의 지능형 무선 센서가 주변 센싱을 통하여 데이터를 수집하고 싱크로 전송한다. 많은 무선 네트워크 응용프로그램이 배터리에 의존하며 배터리를 충전하는 것이 어렵기 때문에 싱크로 수집된 데이터를 전송하기 위해 에너지 효율적인 경로를 설정하는 것은 매우 중요하며 네트워크 수명을 향상시키기 위한 연구는 무선 센서 네트워크에서 가장 중요한 과제 중 하나이다. 본 논문에서는 무선 센서 네트워크에서 일부 센서 노드의 장거리 데이터 전송을 줄여 센서 노드의 에너지 효율을 높이고 네트워크 수명을 향상시키기 위한 체인 기반의 라우팅 모델을 제안한다. 제안하는 라우팅 모델은 작은 세그먼트 단위로 분할된 센싱 영역을 기반으로 체인을 형성하고 데이터를 수집한다. 모의실험을 통하여 제안하는 라우팅 모델과 체인 기반 알고리즘으로 가장 많이 알려진 PEGASIS 및 CSS의 네트워크 수명을 비교 분석하였다. 그 결과에서 제안하는 라우팅 모델의 네트워크 수명이 PEGASIS 및 CCS보다 우수함을 보여주었다.