• Journal of Internet Computing and Services
• /
• v.21 no.6
• /
• pp.95-104
• /
• 2020

In this paper, we propose the real time indoor air quality monitoring and controlling platform on cloud using IoT sensor data such as PM10, PM2.5, CO2, VOCs, temperature, and humidity which has direct or indirect impact to indoor air quality. The system is connected to air ventilator to manage and optimize the indoor air quality. The proposed system has three main parts; First, IoT data collection service to measure, and collect indoor air quality in real time from IoT sensor network, Second, Big data processing pipeline to process and store the collected data on cloud platform and Finally, Big data analysis and visualization service to give real time insight of indoor air quality on mobile and web application. For the implication of the proposed system, IoT sensor kits are installed on three different public day care center where the indoor pollution can cause serious impact to the health and education of growing kids. Analyzed results are visualized on mobile and web application. The impact of ventilation system to indoor air quality is tested statistically and the result shows the proper optimization of indoor air quality.

• Journal of Internet of Things and Convergence
• /
• v.9 no.3
• /
• pp.87-92
• /
• 2023

As times develop, information becomes more diverse and methods of obtaining it become more diverse. About 80% of the amount of information gained in life is acquired through the visual sense. However, visually impaired people have limited ability to interpret visual materials. That's why Braille, a text for the blind, appeared. However, the Braille decoding rate of the blind is only 5%, and as the demand of the blind who want various forms of platforms or materials increases over time, development and product production for the blind are taking place. An example of product production is braille books, which seem to have more disadvantages than advantages, and unlike non-disabled people, it is true that access to information is still very difficult. In this paper, we designed a CNN-based Braille conversion and voice output device to make it easier for visually impaired people to obtain information than conventional methods. The device aims to improve the quality of life by allowing books, text images, or handwritten images that are not made in Braille to be converted into Braille through camera recognition, and designing a function that can be converted into voice according to the needs of the blind.

• Journal of the Korean Society of Safety
• /
• v.32 no.1
• /
• pp.21-26
• /
• 2017

An IoT-based particulate matter (PM2.5) sensing device (PSD) is developed. The PSD consists of a PM2.5 sensor, signal processing circuit, and wi-fi enabled-microprocessor along with temperature and humidity sensors. The PSD estimates PM2.5 density by measuring light scattered by PM2.5. To gauge performance of the PSD, PM2.5 density of open air was measured with the PSD and compared with that of the collocated-government-certified measuring station. Measurements were taken at a sampling frequency of 100 Hz and moving-averaged to remove measurement noise. When compared to the result of the measuring station, average percentile error of PM2.5 density from the PSD is found to be 31%. A correlation coefficient is found to be 0.72 which indicates a strong correlation. Instantaneous variation, however, may far exceed average errors, leading to a conclusion that the PSD is more suitable for estimating average trend of PM2.5 density variations than estimating instantaneous PM2.5 density.

• Journal of Internet of Things and Convergence
• /
• v.3 no.2
• /
• pp.1-5
• /
• 2017

As CCTV technology develops, it is used in various fields. Currently, we want to know about CCTV operation in detail. In addition, CCTV in many fields is causing problems in operation. We plan to design a new system to solve the problem. In this paper, we analyze data using K-means so that CCTV can be operated efficiently, add new technology and function to existing system to increase image technology and operate efficiently, Technology. In addition, we will design a new system for CCTV technology using k-means so that the CCTV can be efficiently operated in the center, and propose the problem to solve the problem.

• Journal of Internet of Things and Convergence
• /
• v.4 no.1
• /
• pp.1-5
• /
• 2018

This paper is concerned with the modeling and identification of time series data corrupted by noise. As modeling techniques, nonsingleton fuzzy logic system (NFLS) is employed for the modeling of corrupted time series. Main characteristic of the NFLS is a fuzzy system whose inputs are modeled as fuzzy number. So the NFLS is especially useful in cases where the available training data or the input data to the fuzzy logic system are corrupted by noise. Simulation results of the Mackey-Glass time series data will be demonstrated to show the performance of the modeling methods. As a result, NFLS does a much better job of modeling noisy time series data than does a traditional Mamdani FLS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.10a
• /
• pp.2-5
• /
• 2021

With the recent development of the Internet of Things (IoT) technology, various terminals are being connected to the Internet. As a result, the amount of IoT data is also increasing, and an index key that can efficient analyze the large-scale IoT data is proposed. Existing index keys have only time and space information, so if data stored in index tables and instance tables were queried using repetition or join operation, IoT data was embedded in the index key of the proposal to create OLAP-based big tables to minimize the number of repetitions or join times.

• Electronics and Telecommunications Trends
• /
• v.19 no.6 s.90
• /
• pp.74-82
• /
• 2004

인터넷의 도입 및 확대가 활발하게 이루어지면서 보다 많은 이용자들은 홈 네트워킹 기반의 정보 가전 기기, 텔레매틱스, 전자 물류 실현을 위한 전자 태크(RFID), 센서 네트워킹 등 모든 사물이 상호 통신할 수 있는 다양한 서비스를 요구하고 있으며 이를 해결하기 위한 연구가 활발히 진행되고 있다. 그러나 현재인터넷의 기반이 되고 있는 IPv4 주소 체계는 약 43억 개의 주소를 생성할 수 있도록 설계되어 있으며, 그 동안 비효율적인 주소 할당으로 유효한 주소는 불과 5~6억 개 정도만을 사용할 수 있는 실정이다. IPv4 기반의 인터넷 주소 체계로는 앞으로 도래할 유무선 통합 서비스 혹은 방송과 통신이 융합되는 사용자 중심의 인터넷 서비스 네트워크 구축에 많은 문제점을 갖고 있기 때문에 주소 자원을 거의 무한대로 제공하는 IPv6 기반의 인터넷(128비트 IPv6 주소는 2128개의 주소 지원) 도입이 필수적이다. 따라서 현재 IPv4 기반의 인터넷에서 IPv6 기반의 차세대 인터넷으로 전환되고 있으며, 또한 라우터 장비 시장은 차별화된 IPv6 기능을 제공하는 장비 중심으로 재편될 것으로 보인다. 본 고에서는 IPv6 라우터에 대한 IPv6 도입 배경 및 프로토콜에 관련된 제반적 기술을 살펴 보고, 이를 기반으로 외국 시스템들의 현재 구현 상태, IPv6 라우터를 개발하는 데 연구되어야 할 주요 사항 및 국내외 IPv6 도입 추진 현황을 살펴 본다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.5
• /
• pp.972-978
• /
• 2016

MACsec is a cryptographic function that operates on Layer 2, the international standard defined in the IEEE 802.1AE. As industries such as IoT(Internet of Things) devices are receiving attention recently are connected to the network and Internet traffic is increasing rapidly, and is exposed to the risk of a variety of Internet attacks. Traditional network security technologies were often made in Layer 3, such as IPsec. However, to be increased as rapidly as the current traffic situation is complicated, and became interested in the security function of protecting the entire traffic instead of for a specific application or protocol. It appeared as these technologies is technology MACsec technology to protect all traffic in Layer 2. In this paper, we propose a Layer 2 security technology adapter MACsec MACsec a technology that allows you to simply and easily add them to the existing Layer 2 networks.

• Journal of Internet of Things and Convergence
• /
• v.5 no.2
• /
• pp.7-13
• /
• 2019

As online shopping is activated by the development of the Internet, consumers' purchase form is changing from the traditional face-to-face purchase method to online purchase method. Many sellers have flowed into shopping malls, and competition among sellers is very intense. Therefore, sellers in shopping malls need to establish rational marketing strategies by analyzing consumer purchase patterns and product sales trends. In this paper, we analyzed the purchase price of consumers by analyzing the product price, rating, and sales quantity of competitors who sell the same product in open shopping malls by time zone. In addition, the collected information was visualized in a chart so that the company's and competitors' sales trends could be easily compared. Using the above system, it is possible to predict the sales volume through the analyzed purchasing pattern and to select the reasonable price of the product by grasping the sales trend.

• Journal of Internet of Things and Convergence
• /
• v.5 no.2
• /
• pp.89-94
• /
• 2019

The purpose of this study was to empirically analyze the motivation of university lifelong education and the factors that are important in selecting it. In the motivation for participation of adult learners, learning new knowledge and skills in the first place and learning new things in the second place were good, so that they could learn together in the third place. Active school investment in faculty and staff will be needed to increase program diversity and quality through professionalism. Adult learners are getting information from the system they are interacting with, and furthermore, they learn the information from the public relations of university professors. Since they are acquiring paths and information through acquaintances, it is necessary to continuously promote the curriculum to unspecified adult learners. Advertisement should take advantage of various convergence strategies such as hanging banners in the area, publicity of the subway, local newspapers, word of mouth, SNS, and the Internet.