• Proceedings of the Korea Information Processing Society Conference
• /
• 2020.11a
• /
• pp.208-211
• /
• 2020

본 논문에서는 디지털 트윈 기술을 비닐하우스 환경 기반으로하여 스마트팜 IoT 재배 관리 환경을 개발하고자 하였다. 유니티를 이용하여 가상 객체를 제작하고 MQTT 프로토콜을 이용하여 데이터베이스와 앱, 가상 환경의 통신 환경을 구축하고, 두 환경을 동시 제어하는 시스템을 구현한 것을 다루고 있다. 이러한 재배 관리 환경을 구현하기 위해 아두이노와 각종 센서들을 사용하여 현실 물리 객체의 환경과 생육 데이터를 수집할 수 있게 하였다. 더 나아가 수집된 데이터를 기반으로 머신러닝을 활용하여 사용자에게 적절한 재배시기와 자동 예측 시스템을 도입한다면 차세대 디지털 트윈 스마트팜 의 시대가 열릴 것이다.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.22 no.4
• /
• pp.5-19
• /
• 2011

The purpose of this study is to identify possible needs for system improvements and reflect them on the operation and development of the system as a result of the usability assessment of an information site in science and technology. For this study, a variety of data collection techniques, including search logs, interviews, and think-alouds, were used. The search log data was processed to quantify four evaluation aspects, which were the effectiveness, efficiency, satisfaction, and errors. The verbal data collected by think-alouds and post-interviews were used to identify possible needs of enhancement in a qualitative analysis. The comparison of the usability before and after the system enhancement revealed an increase of 15 points for effectiveness, 35 seconds decrease in efficiency, 5 points increase in satisfaction, and 1.1 errors decreased, implying an overall improvement of the usability of the current system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.05a
• /
• pp.336-339
• /
• 2011

In the RTLS(Real Time Location Based System), in case of existing a number of moving target, extremely complecated data flow is can be occurred. In the network where single gateway exists, various data which was collected from sensor node is transmitted along the simple route as time goes by. In case of multi-gateway configuration, the collected data is transmitted through diverse routes rather than simple route. This kind of data causes jams on nodes and this brings down the performance of the network. Different from existing studies, in this thesis, MAC (Media Access Control) protocol which minimizes data collision between nodes and guarantees QoS(Quality of Service) is suggested, in order to communicate efficiently in multi-gateway underwater sensor network environment. In the suggested protocol, source node which wants to transmit data makes a channel reservation to a number of destination node using a RTS packet. Source node reserves a channel without collision, by scheduling CTS response time using expected delay information from neighbor nodes. Once the reservation is made, source node transmit data packet without collision. This protocol analyzes/estimates the performance compared to a method provided from existing studies via simulation. As a results of the analysis, it was comfirmed that the suggested method has better performance, such as efficiency and delay.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.4
• /
• pp.815-821
• /
• 2013

In this paper, application layer protocol of C12.22 node, defined by ANSI C12.22 is implemented. ANSI C12.22 defines application layer only among the OSI 7 layers and recommends using the existing protocols for the 1~4 layer to transmit the information. TCP/IP which is one of the generally used protocols has been applied for the transport and network layer protocol in this paper. ANSI C12.19 defines the parameters for the watt-hour meter, and C12.22 application layer defines the network services and data structures networking the watt-hour meter parameters at a minimum. This kind of services and data structures are used for the configuration, programming, monitoring of the networked watt-hour meter or collecting information of the watt-hour meter. A embedded board has been used to implement the C12.22 application layer and a test program for the AMI application server has been developed for the functional test.

• KEPCO Journal on Electric Power and Energy
• /
• v.4 no.2
• /
• pp.75-80
• /
• 2018

The smart city is developing an energy system efficiently through a common management of the city resource for the growth and a low carbon social. However, the smart city doesn't counter a verification effectively about a anomaly pattern detection when existing security technology (authentication, integrity, confidentiality) is used by fixed security key and key deodorization according to generated big data. This paper is proposed the "security nonce generation based on security nonce generation" for anomaly pattern detection of the adversary and a safety of the key is high through the key generation of the KDC (Key Distribution Center; KDC) for improvement. The proposed scheme distributes the generated security nonce and authentication keys to each facilities system by the KDC. This proposed scheme can be enhanced to the security by doing the external pattern detection and changed new security key through distributed security nonce with keys. Therefore, this paper can do improving the security and a responsibility of the smart city platform management data through the anomaly pattern detection and the safety of the keys.

• The KIPS Transactions:PartC
• /
• v.17C no.5
• /
• pp.433-440
• /
• 2010

Energy efficiency, low latency and scalability for wireless sensor networks are important requirements, especially, the wireless sensor network consist of a large number of sensor nodes should be minimized energy consumption of each node to extend network lifetime with limited battery power. An efficient algorithm and energy management technology for minimizing the energy consumption at each sensor node is also required to improve transfer rate. Thus, this paper propose no-overlap multi-pass protocol provides for sensor data transmission in the wireless sensor network environment. The proposed scheme should minimize network overhead through reduced a sensor data translation use to searched multi-path and added the multi-path in routing table. Proposed routing protocol may minimize the energy consumption at each node, thus prolong the lifetime of the sensor network regardless of where the sink node is located outside or inside the received signal strength range. To verify propriety proposed scheme constructs sensor networks adapt to current model using the real data and evaluate consumption of total energy.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.8A
• /
• pp.791-800
• /
• 2010

Recently wireless sensor networks as a field of ubiquitous computing technology was in the limelight. To use and collect the necessary information, Sink node mobility is essential. TTDD(Two-Tier Data Dissemination) proposed most common technique associated with Mobile sink node in wireless sensor networks, but issues exist that the use of many control packet falls into the energy efficiency. The technique for solving problems is Cluster-Based Energy-efficient Routing protocol (CBPER). But CBPER does not transmit the data correctly to sink node or source node. In this paper, we propose An Energy-Efficient Routing Protocol based on Static Grid using mobile sink nodes in order to solve the data transmission failure and reduce the energy consumption in Wireless Sensor Networks. We have evaluated it with the NS-2 simulator. Our results show that the proposed protocol saves the energy consumption up to 34% in comparison with CBPER. We also prove that the proposed protocol can transmit more accurate data to the sink de than CBPER.

• Journal of Internet Computing and Services
• /
• v.11 no.4
• /
• pp.33-39
• /
• 2010

In this paper, a data dissemination protocol that transmits data collected for Wireless Sensor Networks (WSNs) is newly proposed, and the proposed proactive protocol takes into account energy consumption minimized and delay time disseminated. The well-known SPMS (Shortest Path Mined SPIN) forms the shortest path-based routing table obtained by Bellman Ford Algorithm (BFA) and disseminates data using a multi-hop path in order to minimize energy consumption. The mentioned properties of SPMS cause memory burden to create and maintain the routing tables. In addition, whenever BFA is executed, it is necessary to suffer from the energy consumption and traffic occurred. In order to overcome this problem, a proactive dissemination protocol using Residual Energy and Signal Strength, called RESS, is proposed in this paper. Simulation results show that RESS outperforms SPMS up to 84% in terms of the number of traffic messages and the transmitted delay time of RESS is similar to that of SPMS using the shortest path.

• Journal of the Korea Society for Simulation
• /
• v.15 no.4
• /
• pp.29-39
• /
• 2006

Sensor networks consist of small nodes with sensing, computation, and wireless communications capabilities. A number of routing protocols to transmit the data between the base station and sensor nodes have been proposed. Intanagonwiwat et al. proposed the directed diffusion in which the base station sends interest messages and waits for data from the nodes in the specific regions. Since the directed diffusion propagates every interest message to whole nodes in the network, it causes energy dissipation of nodes. In this paper, we propose a novel data propagation method, which limits the data transmission area according to a threshold value for reducing the energy consumption in the network. A fuzzy logic is exploited to determine the threshold value by considering the energy and density of all the deployed nodes. The simulation models are designed and implemented based on DEVS formalism which is theoretically well grounded means of expressing discrete event simulation models.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.2B
• /
• pp.76-81
• /
• 2008

LEACH (Low Energy Adaptive Clustering Hierarchy) has been proposed as a routing protocol with a hierarchical structure, in order to achieve the energy efficiency that is of primary importance in the wireless sensor networks. A wireless sensor network adopting LEACH is composed of a few clusters, each of which consists of member nodes that sense the data, and head nodes that deliver the collected data from member nodes to a sink node that is connected to a backbone network. A head node in a cluster allocates TDMA slots to its member nodes without taking into account whether they have data to transmit or not, thus resulting in inefficiency of energy usage of head node that remains in active mode during the entire round time. This motivates us to propose a scheme to improve the energy efficiency of LEACH, by assigning TDMA slots only to those member nodes who have data to send. As a result, the head node can remain sleep during the period of no data transmission from member nodes, leading to the substantial energy saving. By using the ns-2 simulator, we evaluate the performance of the proposed scheme in comparison with the original LEACH. Experimental results validate our scheme, showing a better performance than original LEACH in terms of the number of outliving nodes and the quantity of energy consumption as time evolves.