• Journal of the Semiconductor & Display Technology
• /
• v.21 no.1
• /
• pp.103-107
• /
• 2022

Scaffolds are the structures that safely protect sensors in various parts of the body. Because of scaffolds must protect sensors from load, the tensile strength of the scaffolds must be higher than 750 kgf/cm². Currently, the tensile strength of scaffolds made with the 3d printer is 714 kgf/cm². We confirm that the tensile strength of the scaffolds increase using air with high nitrogen concentration. In this study, we conducted experiments to find nitrogen concentrations in which the tensile strength of the specimen is higher than 750 kgf/cm². The nitrogen control device and the nitrogen concentration sensor were installed in the chamber type 3d printer. The nitrogen concentration inside the 3d printer was changed by 5 % from 80 % to 100 %. Specimens of ASTM D 638 standard were produced under changed nitrogen concentration. We measured the tensile strength of specimens. We compared the tensile strength of specimens produced under each nitrogen concentration. We confirmed that when air with nitrogen concentration of 90 % was used, the tensile strength of scaffolds were 762 kgf/cm².

• Journal of Biomedical Engineering Research
• /
• v.44 no.6
• /
• pp.363-376
• /
• 2023

According to the COVID-19, development of various medical software based on IoT(Internet of Things) was accelerated. Especially, interest in a central software system that can remotely monitor and control ventilators is increasing to solve problems related to the continuous increase in severe COVID-19 patients. Since medical device software is closely related to human life, this study aims to develop central monitoring system that can remotely monitor and control multiple ventilators in compliance with medical device software development standards and to verify performance of system. In addition, to ensure the safety and reliability of this central monitoring system, this study also specifies risk management requirements that can identify hazardous situations and evaluate potential hazards and confirms the implementation of cybersecurity to protect against potential cyber threats, which can have serious consequences for patient safety. As a result, we obtained medical device software manufacturing certificates from MFDS(Ministry of Food and Drug Safety) through technical documents about performance verification, risk management and cybersecurity application.The purpose of this study is to conduct a usability assessment to ensure that ergonomic design has been applied so that the ventilator central monitoring system can improve user satisfaction, efficiency, and safety. The rapid spread of COVID-19, which began in 2019, caused significant damage global medical system. In this situation, the need for a system to monitor multiple patients with ventilators was highlighted as a solution for various problems. Since medical device software is closely related to human life, ensuring their safety and satisfaction is important before their actual deployment in the field. In this study, a total of 21 participants consisting of respiratory staffs conducted usability test according to the use scenarios in the simulated use environment. Nine use scenarios were conducted to derive an average task success rate and opinions on user interface were collected through five-point Likert scale satisfaction evaluation and questionnaire. Participants conducted a total of nine use scenario tasks with an average success rate of 93% and five-point Likert scale satisfaction survey showed a high satisfaction result of 4.7 points on average. Users evaluated that the device would be useful for effectively managing multiple patients with ventilators. However, improvements are required for interfaces associated with task that do not exceed the threshold for task success rate. In addition, even medical devices with sufficient safety and efficiency cannot guarantee absolute safety, so it is suggested to continuously evaluate user feedback even after introducing them to the actual site.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.19 no.4
• /
• pp.29-41
• /
• 2017

Because infants lack full communication skills and are not active main agents, nurturing and protection are essential. The value of smart devices that can help prevent potential threats and manage infant care is evaluated highly. This study offers basic research data that contributes to the development of devices for infant and parents as well as to future planning. This study compared and analyzed literature materials and visual materials based on news articles, advanced research, and official websites of brands. The research ranges and subjects are wearable devices for infants that were released or will be released between 2014 and 2017. Wearable devices that help protect and manage infant care are roughly separated into clothing, accessory, and the like. In this study, four kinds of clothing products, six kinds of accessories products, and fifteen kinds of other products were researched and a total of 25 kinds of products were analyzed. Categories was made in accordance with morphological characteristics, main features, materials and the design of wearable devices for infants depending on the device features. Wearable devices for infants that will be developed in the future must be based on a variety of suggestions in order to know best how to attach a sensor to an infant. From this study, the deduced trend analysis of wearable devices for infants can suggest new ways for follow-up studies as well as product development.

• Journal of the Korea Convergence Society
• /
• v.9 no.4
• /
• pp.9-14
• /
• 2018

Recently, as the internet speed is getting faster, in the cloud environment, the service receiving device is changing from a general PC to a compact device such as a mobile phone or a tablet PC. Since handheld devices such as mobile phones or tablet PCs are often used in wireless rather than wired, there are many problems that personal information may be exposed maliciously from a third party. In this paper, we propose a user privacy protection scheme through a duplicate duplicate key generation process which can safely protect user 's privacy from third party among cloud services being served through various wireless media. The proposed scheme is used to synchronize the duplicated key between the server and the intermediary device, and aims at shortening the time of the authentication process protecting the user 's privacy. In this case, the proposed scheme uses Interleave() function and random number to synchronize the server and the intermediary device, so it can safely prevent the malicious attack of the third party.

• Journal of Korea Multimedia Society
• /
• v.12 no.4
• /
• pp.550-558
• /
• 2009

In ubiquitous environment, more small, lightweight, cheap and movable device is used than one device used in wired network environment. Multimedia service which is anytime, anywhere, is provided by device. However, it does not ensure the fair use of multimedia contents and causes damage to the contents providers because of illegal copy and distribution and indiscriminate use of digital contents. For solving this problems, DRM is applied to wired network but it has the problems does not protect stored license and manage license completely because of depending on simple protection such as device authentication and cryptographic algorithm. This paper proposes the license management model using digital forensic and DRM that prevents contents and licenses from distributing illegally and also enables the creation of evidence for legal countermeasure and the protection of license in whole life cycle.

• Journal of Korea Society of Industrial Information Systems
• /
• v.17 no.1
• /
• pp.11-20
• /
• 2012

Due to the development of internet technology, the online business trade becomes an active area. Online negotiation supporting systems have been developing very actively in recent years to meet the growing needs. We have been studying on the effect that the haptic device brings about in interaction through online negotiation between two parties. In order to meet the online negotiation's requirements, the developed interface should be able to protect user's anonymity, convey user's emotion and make the scene alive.In this study, we adopt haptic interaction as a means of conveying emotion in an online negotiation between Japanese and Chinese people. In this study, our goal is to investigate the effectiveness of haptic interaction in communications between Chinese and Japanese users and analyze the characteristis in operation the haptic device. We conducted online negotiation experiments with and without haptic interaction . The comparison experiments results show that the haptic feedback can help to convey the emotion and the sense of presence. The Chinese subjects' feedback for the questionaire concerning the emotional communication and the sense of presence varies slightly compared to the Japanese subjects. We also found when using the haptic device, the force feedback can influence subject's feelings.There is little significant difference between the advanced and the medium subjects in negotiation dialogues and the haptic device's operation, the beginner subjects are slightly at a disadvantage.

• The Journal of the Korea Contents Association
• /
• v.15 no.5
• /
• pp.27-35
• /
• 2015

Depending on the smart device user growth and development of communication technology, the area about working environment was extended without constraints of time and places. It is introducing to work using user's devices and this environment is called 'BYOD(Bring Your On Device)'. But it is vulnerable to security threat that happened in existing wireless environment and its security threat issue which is caused by inside information leak by an inside job and lost or stolen terminal which is caused by careless user is getting heated. So we studied about access control protocol by user rights under the BYOD situation make a session key based on the user information. We make a session key based on the user information and user device information, after that we design an access control protocol. The protocol we suggest can protect from attack under the BYOD situation and wireless communication situation and also safety and security requirement from inside information leak because it controls user rights.

• Journal of Communications and Networks
• /
• v.18 no.4
• /
• pp.589-599
• /
• 2016

Most existing resource management problem models arise from the original desire of allocating resources in either a user-centric or network-centric manner. The difference between their objectives is obvious: user-centric methods attempt to optimize the utility of individual users, whereas network-centric models intend to optimize the collective utilities of the entire network. In this paper, from the above two aspects, we analyze the robust power control problem in device-to-device (D2D) communication underlaying cellular networks, where two types of channel uncertainty set (e.g., ellipsoidal and column-wise) are considered. In the user-centric method, we formulate the problem into the form of a Stackelberg game, where the energy efficiency (EE) of each user is the ingredient of utility function. In order to protect the cellular user equipment's (CUE) uplink transmission, we introduce a price based cost function into the objectives of D2D user equipment (DUE). The existence and uniqueness of the game with the influence of channel uncertainty and price are discussed. In the network-centric method, we aim to maximize the collective EE of CUEs and DUEs. We show that by the appropriate mathematical transformation, the network-centric D2D power control problem has the identical local solution to that of a special case of the user-centric problem, where price plays a key role. Numerical results show the performance of the robust power control algorithms in the user-centric and network-centric models.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.14 no.2
• /
• pp.3-13
• /
• 2004

DRM is the ability to brand digital contents with features that ensure copy Protection and affect the way in which digital contents are played back. DRM is a technology that enables the secure distribution, promotion and sale of digital contents on the Internet. The DRM Client System that operates on the untrusted user environments has to meet the requirements of the contents owner, including copyright and contents protection. After the DRM Client System is installed on the untrusted user environments, it verifies and plays digital contents. With these procedures it cuties out user authentication, contents decryption, and license management. During these procedures, the sensitive data, including authentication information, decryption data and license data, must be secured against any illegal access from users. The goal of this thesis is to introduce the implementation of Secure Storage Device which can protect user's authentication key, cryptographic key, and license data in safe where the DRM Client System is running.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.12
• /
• pp.4946-4960
• /
• 2020

In a device-to-device (D2D) underlaid cellular network, there exist two types of co-channel interference. One type is inter-layer interference caused by spectrum reuse between D2D transmitters and cellular users (CUEs). Another type is intra-layer interference caused by spectrum sharing among D2D pairs. To mitigate the inter-layer interference, we first derive the interference limited area (ILA) to protect the coverage probability of cellular users by modeling D2D users' location as a Poisson point process, where a D2D transmitter is allowed to reuse the spectrum of the CUE only if the D2D transmitter is outside the ILA of the CUE. To coordinate the intra-layer interference, the spectrum sharing criterion of D2D pairs is derived based on the (signal-to-interference ratio) SIR requirement of D2D communication. Based on this criterion, D2D pairs are allowed to share the spectrum when one D2D pair is far from another sufficiently. Furthermore, to maximize the energy efficiency of the system, a resource allocation scheme is proposed according to weighted graph coloring theory and the proposed ILA restriction. Simulation results show that our proposed scheme provides significant performance gains over the conventional scheme and the random allocation scheme.