• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.5
• /
• pp.231-237
• /
• 2017

This paper presents an implementation of a smart flowerpot which can adjust humidity and illumination automatically after monitoring the temperature, humidity, and illumination. We made a container of the flowerpot with a 3D printer and embedded a NodeMCU micro controller in it. We attached a temperature sensor, a humidity sensor, an illumination sensor, and a water pump to the NodeMCU. We developed a control program that adjusts humidity and illumination and ran it on the NodeMCU. Also we developed an Android application and set up an MQTT server. Using the MQTT server, the NodeMCU and the Android application can exchange messages which keep sensor values and commands. Using the Android application. the user can send the proper temperature, humidity, and illumination to the smart flowerpot and monitor the sensor values.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.475-477
• /
• 2017

In this paper Wifi robot car working as web sever on wifi network was implemented using NodeMCU ESP-12E board and its operation was verified using web browser of smart phone and PC. Current research result can be applicable to Wifi home automation applications with ESP-12E board.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.56 no.3
• /
• pp.117-122
• /
• 2007

In this paper, we described a design and implementation of a sensor node for environmental monitoring. The main focus of design for sensor nodes is to isolate MCU for treating sensors from the RF module for considering various communication environment. The second is to make the interface between MCU and varity of sensor. In addition, we choose a narrow band communication module, cc1020, for the admittance of Korea government communication law. We also use a uC/OS-II as an operating system which is famous for 8bit MCUs. We showed that the communication performance is sufficient to use the communication module in a out-door environment through several experiments in that it is possible to transmit between 100m distance through experiments in a mountain.

• Journal of IKEEE
• /
• v.16 no.3
• /
• pp.274-282
• /
• 2012

In this paper, we propose the design of lighting control algorithm for intelligent LED lighting system. The proposed lighting control algorithm transmitted to MCU through a data bus the environmental information detected from respectively sensor node. The MCU control software was designed to determine the level maintained to depending on the set control method by comparing the results that calculated the dimming level using a signal value. Also, it was designed to be lighting by cross-performed periodically the rotation and reverse method by created fully symmetrical pattern using the control algorithm to LED lighting device. In this paper, the proposed lighting control algorithm improved the reliability of the data sent by designed the system that can be controlled lighting to stable, and it was maintained the event delivery ratio of 91%. Also, the lighting device was decreased the luminous intensity of 32%, the power consumption of 49%, and heat generation of 32%. As a result, it were could be improved the energy efficiency that the life-cycle of LED has been increased 50%.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.9
• /
• pp.1928-1934
• /
• 2009

This paper proposes a power management scheme for sensor nodes in wireless sensor networks based on sensor node operating system supporting the sensor transparency, which can turn off the sensors when the MCU is in sleep mode. We classify the sensors in two types, that is, event sensors and polling sensors, to be able to decide whether the sensor is a type of sensors whose power supply can be turned off or not, and we design a new scheduler to support recognition of those different types of sensors. Implementing and evaluation of the scheduler and the power manager supporting sensor transparency are shown based on Nano-Q+.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.11
• /
• pp.1574-1579
• /
• 2016

This paper presents a self-powered sensor-node scheme using a RF wireless power harvesting techniques for improve drone time of flight. Sensor-node that is proposed is turned when two conditions satisfy: The one is input RF ID data from master-node should be same with sensor-node's ID, and the other one is RF wireless power harvesting system is turned on by hysteresis switch. In this paper, master-node's output is 26 dBm at 263 MHz. Maximum RF to DC power conversion efficiency is about 55% at 4-6 dBm input power condition (2 meter from master-node). The maximum RF wireless power harvesting range is about 13 meter form master-node. And power consumption of the sensor-node's load elements such as transmitter, MCU and temperature sensors is approximately average 15 mA at 5.0 V for 10 msec.

• Proceedings of the KIEE Conference
• /
• 2007.11c
• /
• pp.77-82
• /
• 2007

In this paper, we described a design and implementation of a sensor node for environmental monitoring. The main focus of design for sensor nodes is to isolate MCU for treating sensors from the RF module for considering various communication environment. The second is to make the interface between MCU and varity of sensor. In addition, we choose a narrow band communication module, cc1020, for the admittance of Korea government comminication law. We also use a uC/OS-II as an operating system which is famous for 8bit MCUs. We showed that the communication performance is sufficient to use the communication module in a out-door environment through several experiments in that it is possible to transmit between loom distance through experiments in a mountain.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.8 no.1
• /
• pp.76-81
• /
• 2009

The transmitting node in WSN for ITS would be small and operated by battery, and the MCU in the node would be low speed with small sized memory and low power consumption. In this paper, the post-checksum method in which the checksum field is added to the tail of the TCP segment for ITS applications, is proposed to reduce data processing time and power consumption, and so there is no limitation of the transmitting data size.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.6
• /
• pp.2781-2798
• /
• 2019

Thanks to internet, as one of indispensable parts of our lives, many devices that we use in our daily lives like TV, air conditioner, refrigerator, washing machine, can be monitored and controlled remotely by becoming more intelligent via Internet of Things (IoT) technology. Smart Home applications as one of the elements of smart cities, are individually the most demanded application without question. In this study, Smart Energy Management (SEM) system, based on NodeMCU and Android, has been designed for SEM, which is a part of the smart home application. With this system, household energy consumption can be monitored in real time, as well as having the ability to record the data comprising of operation times and energy consumption information for each device. Additionally, it is ensured to meet the energy needs on a maximized level possible, during the hours when the energy costs are lower owing to the SEM system. The Android interface provides the users with the opportunity to monitor and change their electricity consumption habits in order to optimize the energy efficiency, along with the opportunity to draw up of a daily and weekly schedule.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.47 no.3
• /
• pp.1-4
• /
• 2010

RS-485, communication bases from small network system must prepare in collision. The collision is that mean the data transfer breaks. For a stabilized communication chooses 1:N polling methods. But polling is low speed in addition to maybe overload Master device. So, usual N:N Prefers a communication. In this case, must be preparing to avoid collision or some solutions. Generally, to after collision retransmits after short time. It's called delay time for short time. When making a delay time, uses address of each systems. (Address of each node) If the many nodes collided, the each node has different delay time. When making a delay time, uses a usual random number. Making a random number is hard job. So uses a usual pseudorandom number. It is more difficult from small size MCU. The Chaos random number provides stabled value. Finally, when uses the Chaos random number, the stability and reliability of system get better.