• Journal of Digital Convergence
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• v.14 no.2
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• pp.259-264
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• 2016

In this paper, we proposed an arduino-based smart green house management system model and implemented it. The proposed system consists of control unit composed of sensors and arduino, agent program controlling the green house, and web applications providing user interfaces. The control unit transmits data of sensors such as temperature, humidity, illuminance, moisture, etc. to the agent program, and then the agent saves the data in its database. In reverse, control data are transmitted from agent program to control unit. Users can monitor sensed data of green houses and control actuators remotely using web. Plus, smart green house management is available by context awareness and autonomous control functions of the proposed system.

• The Journal of the Acoustical Society of Korea
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• v.41 no.2
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• pp.242-253
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• 2022

When the source waveform is unknown, the Green's function can be estimated by Ray-based Blind Deconvolution (RBD) based on the simple array signal processing. In previous papers, RBD was successfully demonstrated using simulation and experiments in shallow water environment. In this paper, we investigate the applicability of RBD for a long-range communication (e.g., 30 km, 60 km, and 90 km) in a deep water environment (1,000 m ~), using experimental data conducted in the east of Pohang, South Korea, in October 2018. Data results are presented to demonstrate Green's function estimation of a communication signal (2.2 kHz ~ 2.9 kHz) using a 16-element, 42-m long vertical array. The results show that the Green's function estimated from RBD is comparable to that of matched filter result. Additional communication performance at a maximum range of 90 km will be also presented.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.2
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• pp.326-354
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• 2014

In this paper, a new green clustering algorithm is proposed to be as a first approach in the framework of an energy efficient strategy for centralized enterprise high-density WLANs. Traditionally, in order to maintain the network coverage, all the APs within the WLAN have to be powered-on. Nevertheless, the new algorithm can power-off a large proportion of APs while the coverage is maintained as its always-on counterpart. The two main components of the new approach are the faster procedure based on K-means and the more accurate procedure based on Evolutionary Algorithm (EA), respectively. The two procedures are processes in parallel for different designed requirements and there is information interaction in between. In order to implement the new algorithm, EA is applied to handle the optimization of multiple objectives. Moreover, we adapt the method for selection and recombination, and then introduce a new operator for mutation. This paper also presents simulations in scenarios modeled with ray-tracing method and FDTD technique, and the results show that about 67% to 90% of energy consumption can be saved while it is able to maintain the original network coverage during periods when few users are online or the traffic load is low.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.527-531
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• 2015

With the mounting concerns over environmental issues, green construction is gaining a place in the global construction industry. However, rare research has been conducted to analyze green construction projects, especially in the aspect of project schedule performance. As a result, this study aims to investigate the degree of project delay in green building construction, analyze the factors affecting schedule delay of green building projects, and finally provide recommendations to improve schedule performance of green building project. To achieve the objectives, a comprehensive literature review was carried out, followed by a survey conducted with 30 companies that provided data from 220 traditional and 96 green building projects. The analysis of the responses identified that 15.9% of the traditional building projects were delayed while 32.3% of the green building projects were completed behind schedule. Furthermore, the amount of the delays in green building projects was an average of 4.8% of their planned schedule. The top 5 critical factors that can cause delay in green building projects were identified as: (1) speed of decision-making by clients; (2) speed of decision-making involving all project teams; (3) communication/coordination between key parties; (4) level of experience of consultants; and (5) difficulties in contractors' project financing. Lastly, a list of recommendations was introduced, aiming to reduce schedule delay in green building construction projects based on the observations. This study will serve as s a base for further research on the enhancement of green building project schedule performance.

• Journal of the Korean Institute of Rural Architecture
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• v.14 no.1
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• pp.115-124
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• 2012

The purpose of this study is to derive and to apply green factors focusing on the existing old settlements, Topdong 'Yangdalmal' in Cheongju City. This study is conducted through literatures and GBCC (Green Building Certification Criteria) review. Literatures cover the traditional characteristics of farming village and the modern characteristics of urban space today. The results are following as; first, Land Use, Environment, Resource and Energy are the most important green factors by literatures and GBCC. Second, traditional elements and natural elements such as history and culture, natural resource use and passive planning are added. Finally information communication is added as the green factor showed feature of modern society.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.219-226
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• 2021

LED-to-LED VLC is a technology that uses LEDs as both a transmitter and a receiver unlike the typical VLCs. In this paper, we experimentally demonstrate a micro LED-to-LED VLC using Micro LED. We tested all the possible VLC cases using red, yellow, green, blue, and white color LED as both a transmitter and a receiver, and measured rise time and SNR. Then we calculated channel capacity depending on the LED color sets. Our experimental results show that the best channel capacity is 125 kbps when the transmitter micro LED was blue and the receiver LED was green. We also measured BERs of VLCs using OFDM signal, and we showed a successful micro LED-to-LED VLC upto 250 kbps.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.2
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• pp.142-147
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• 2015

The artificial light sources for growth of plant are usually high-pressure sodium lamp, metal haloids lamp, and fluorescent light; however, these light sources have relatively weaker Red and Blue lights that are necessary for growth of plants. Especially the effect of Photosynthetic Photon Flux Density (PPFD) is pointed out as the weakness. Meanwhile, LED light source can be selected by specific wavelength to greatly improve the effect of PPFD. In this regard, this paper aims to investigate the promotion of plant growth by measuring photosynthetic photon flux density (hereafter referred to as PPFD) according to changes in light quality of the LED light sources. Towards this end, LED light sources for plant growth were produced with 4 kinds of mono-chromatic lights and 6 kinds of combined lights by mixing red, blue, green and white lights. A comparative analysis was conducted to investigate the effects of optical properties and PPFD on plants (green leaf lettuce) using the produced light sources. The results monochromatic light has fastest growth rate, but plant growth conditions have poor. This being so, mixed light is suitable for the green leaf lettuce.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.2
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• pp.121-131
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• 2011

Green Marketing, a response to the serious environment problems of the 21st century, is an important point for trends in both art and fashion. It is a strategy for reminding consumers of the threatening environment problems and to recognize that everyone must take responsibility for these problems. Green marketing is a concept that is the point at issue and social reform movement. The purpose of this study was to find examples of Green Marketing in fashion and classify them into four groups. The results of this study were as follows. First, the terms related to green marketing as related to fashion can be categorized into four areas: 1. Eco-friendly product marketing: product merchandising that usually uses organic materials and green manufacturing processes. 2. Green-communication marketing: PR strategies that use green slogans through deep impression advertising or special promotional events relating reducing, reusing and recycling, etc., with the brand's name. 3. Green environmental-marketing: marketing strategies that is an enlightenment campaign for environmental preservation and sustainable fashion design such as reusing, recycling, and reducing. 4. Cause-related marketing: marketing plans that return profits to society and that take an active part in the causes of the community. It was expected that these types of green marketing strategies would yield positive effects in enhancing brand value and consumer confidence as well as increasing profits.

• Journal of the Korea Convergence Society
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• v.6 no.6
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• pp.147-152
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• 2015

Eco-friendly or green is a key word which we use in our life. There are examples such as eco-friendly laundry detergent and agricultural products or green car and home, Due to the indiscriminate development, it was caused severe environmental pollution. Green IT is a necessary technology to solve the energy and environmental problems and to increase the productivity of corporations. Therefore, we studied contents related with green IT. The history for green IT has changed from 'Green of IT' to 'IT for Green'. Studies for 'IT for Green' progress extensively on today. In this paper, we described a transition progress and characteristics of green IT. Lastly, we analyzed smart work in the examples of the top.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.5
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• pp.688-695
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• 2013

Networked Control Systems(NCS) contain the structure which controllers, actuators and sensors are connected to communication network. And they have been adopted in large and complicated plant area due to the advantages of mitigating computational bottleneck and maintenance. Although this structure provides many benefits, it brings in problems of unpredictable communication delay, data loss and corruption. This phenomena have to be considered in designing NCSs since it affects on overall control system stability. This paper introduces network traffic test method for ethernet based NCSs to find out maximum network usage which guarantee stable control operation. Test results shows this methods can be adopted in various types of NCSs and contributes economical system design and effective system operation.