• Membrane Journal
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• v.33 no.4
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• pp.181-190
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• 2023

Wastewater purification is one of the most important techniques for controlling environmental pollution and fulfilling the demand for freshwater supply. Various technologies, such as different types of distillations and reverse osmosis processes, need higher energy input. Capacitive deionization (CDI) is an alternative method in which power consumption is deficient and works on the supercapacitor principle. Research is going on to improve the electrode materials to improve the efficiency of the process. A reverse electrodialysis (RED) is the most commonly used desalination technology and osmotic power generator. Among many studies conducted to enhance the efficiency of RED, MXene, as an ion exchange membrane (IEM) and 2D nanofluidic channels in IEM, is rising as a promising way to improve the physical and electrochemical properties of RED. It is used alone and other polymeric materials are mixed with MXene to enhance the performance of the membrane further. The maximum desalination performances of MXene with preconditioning, Ti₃C₂T_x, Nafion, and hetero-structures were respectively measured, proving the potential of MXene for a promising material in the desalination industry. In terms of osmotic power generating via RED, adopting MXene as asymmetric nanofluidic ion channels in IEM significantly improved the maximum osmotic output power density, most of them surpassing the commercialization benchmark, 5 Wm^-2. By connecting the number of unit cells, the output voltage reaches the point where it can directly power the electronic devices without any intermediate aid. The studies around MXene have significantly increased in recent years, yet there is more to be revealed about the application of MXene in the membrane and osmotic power-generating industry. This review discusses the electrodialysis process based on MXene composite membrane.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.337-343
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• 2014

The PRT(Personal Rapid Transit) in material or immaterial guided tracks is operated automatically according to the needs of passengers with the optimal non-stop path from the source to the destination. In recent years, the personal rapid transit (PRT) system, which affords superior accessibility and ease of use, has been spotlighted as a new transport system for the future. In this study, a method for vertical lifting of PRT vehicles was proposed to facilitate interlink with other means of transport and thereby improve the efficiency of door-to-door transport. For this purpose, operation control interfaces were designed and experiments were conducted. Programmable Logic Controller (PLC) dedicated for the PRT vertical lift was designed to interface with Operation Control Center (OCC) by Modbus TCP over Ethernet. We implemented a 3D graphical PRT operation simulator which can emulate the mixing operation of the virtual vehicles and the actual vehicles.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.9
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• pp.1623-1632
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• 2008

In food choice, consumers consider importantly food safely and reliability focusing on a high qualify control. Also they are concerned about sustainable production and consumption considering of area and environment. In this paper, We propose and design the high-quality seafood production support system that is based on international sanitary standard haccp, traceability and eco-fiendly seafood certification for safety and reliability of the seafood production. The system is categorized into five part: aquafarm haccp, environmental control monitoring, traceability, disease prevention and messenger service and seafood price inquiry service. The proposed system utilize diverse ubiquitous-it technologies like usn, network cctv, mobile device etc.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.295-302
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• 2016

Many countries, especially ICT powers, are supporting IoT-based technology at a national level and this technology is actively being researched in the businesses and research institutes in an aim to develop technology and create an ecosystem. Roads in the Seoul city are building public facilities based on IoT to provide various services and conveniences for the users. However, for the full-fledged introduction and development of IoT, there are many cases where infringement on security and privacy and threat for life and safety happen. Also, as the IoT environment includes various environment technologies such as the existing sensor network, heterogeneous communication network, and devices optimized for the IoT environment, it inherits the existing security threat and various attack techniques. This paper researches the attribute based encryption technology for safe communication in the IoT environment. The data collected from the device is transmitted utilizing the attribute based encryption and by designing the key generation protocol, grades and authorities for the device and users are identified to transmit safe messages.

• Journal of Digital Convergence
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• v.13 no.4
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• pp.205-210
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• 2015

The auto industry has significantly evolved to the extent that much attention is paid to M2M (Machine-to-Machine) communication. In M2M communication which was first used in meteorology, environment, logistics, national defense, agriculture and stockbreeding, devices automatically communicate and operate in accordance with varying situations. M2M system is applied to vehicles, specifically to device-to-device communication inside cars, vehicle-to-vehicle communication, communication between vehicles and traffic facilities and that between vehicles and surroundings. However, communication systems are characterized by potential intruders' attacks in transmission sections, which may cause serious safety problems if vehicles' operating system, control system and engine control parts are attacked. Thus, device-to-device secure communication has been actively researched. With a view to secure communication between vehicular devices, the present study drew on hash functions and complex mathematical formulae to design a protocol, which was then tested with Casper/FDR, a tool for formal verification of protocols. In brief, the proposed protocol proved to operate safely against a range of attacks and be effective in practical application.

• Journal of Digital Convergence
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• v.18 no.3
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• pp.171-177
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• 2020

Under the influence of the Fourth Industrial Revolution, there are many tries to promote productivity enhancement and competitiveness by adapting smart farm technology that converges ICT technologies in agriculture. This smart farming technology is emerging as a new paradigm for future growth in agriculture. The development of real-time cultivation environment monitoring and automatic control system is needed to implement smart farm. Furthermore, the development of intelligent system that manages cultivation environment using monitoring data of the growth of crops is required. In this paper, a fast and efficient development method for implementing a cloud-based smart farm management system using a highly compatible and scalable web platform is proposed. It was verified that the proposed method using the web platform is effective and stable system implementation through the operation of the actual implementation system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.33-38
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• 2009

Recently most of A/V devices are being adopted hi-tech of A VRCP and changed to mobile environment. AVRCP is designed to provide a standard interface to control A/V devices, hi-fi equipment, or others to allow a single remote control or other device to control all the A/V equipment to which a user has access. It may be used in concert with A2DP or VDP. The AVRCP defines two roles, that of a controller and target device. In AVRCP, the controller translates the detected user action to the A/V control signal, and then transmits it to a remote Bluetooth enabled device. It can be small and mixed mobile devices using bluetooth technologies. The functions available for a conventional infrared remote controller can be realized in this protocol. The remote control described in this protocol is designed specifically for A/V control only. We designed new DSP using Adaptive Acoustic Echo Canceller for bluetooth hands free based this AVRCP standard specifications.

• Analytical Science and Technology
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• v.11 no.1
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• pp.1-7
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• 1998

This study focuses on developing a controlling and analyzing software for the portable atomic emission spectrometer equipped with an electrothermal vaporizer(ETV) that can perform the in-situ trace analysis of heavy metal ions dissolved in water. The software works well for a notebook PC and it is exclusively developed for the real time analysis with a line filter and a photomultiplier light detector. The program is designed to operate under Windows 95 environment and either Korean or English can be used as a main language. The Delphi 2.0 language software is mainly used for programing. The program is designed to make a calibration curve and the system users can get the analytical data in a short time. And a final report can be generated without having difficulties. This software can be easily modified for other analytical atomic spectrometers.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.393-399
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• 2013

Recently, the quantity and type of data that is being processed in cloud environment are varied. A method for easy access in different network in a heterogeneous environment of big data stored in the device is required. This paper propose security management method for smoothly access to big data in other network environment conjunction with attribute information between big data and user. The proposed method has a high level of safety even if user-generated random bit signal is modulated. The proposed method is sufficient to deliver any number of bits the user to share information used to secure recognition. Also, the security awareness information bit sequence generated by a third party to avoid unnecessary exposure value by passing a hash chain of the user anonymity is to be guaranteed to receive.

• Tunnel and Underground Space
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• v.28 no.4
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• pp.372-386
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• 2018

The air quality near the backfilled site area is significantly deteriorated during and even after the curing period of the backfill materials. Hazardous gases such as NH3 and CO2 may leak out prolongedly from the mined-out sites backfilled with the composite carbonate-based material; leakage can be observed at the underground working sites as well as on the surface. At operating mines, underground gas leakage will severely aggravate the workplace environment. The ventilation schemes should supply sufficient air to dilute the contaminated air, and control the toxic gas leakage and dispersion. This study shows the applicability of pressurization ventilation system to control gas leakage and dispersion at the backfilled underground mine site.