• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.10
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• pp.2883-2902
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• 2023

Since the existing anti-jamming methods, including intelligent methods, have difficulty against high-speed reactive jamming, we studied a new methodology for jamming utilization instead of avoiding jamming. Different from the existing jamming utilization techniques that harvest energy from the jamming signal as a power supply, our proposed method can take the jamming signal as a favorable factor for frequency detection. Specifically, we design an intelligent differential frequency hopping communication framework (IDFH), which contains two stages of training and communication. We first adopt supervised learning to get the jamming rule during the training stage when the synchronizing sequence is sent. And then, we utilize the jamming rule to improve the frequency detection during the communication stage when the real payload is sent. Simulation results show that the proposed method successfully combated high-speed reactive jamming with different parameters. And the communication performance increases as the power of the jamming signal increase, hence the jamming signal can help users communicate in a low signal-to-noise ratio (SNR) environment.

• Journal of Korea Society of Industrial Information Systems
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• v.24 no.6
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• pp.43-53
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• 2019

In recent years, there have been many cases of damage to indoor air hazardous materials, and major damage due to the lack of quick action. In this regard, the system is intended to establish for sending push messages to the user's mobile when the concentration of hazardous substances is exceeded. This system extracts data with IoT system such as Arduino and Raspberry Pi and then constructs database through MongoDB and MySQL in cloud computing system. The database is imported through the application server using NodeJS and sent to the application for visualization. Also, when receiving signals about a dangerous situation in IoT system, push message is sent using Google FCM library. Mobile application is developed using Android Web view, and page to enter Web view is developed using HTML5 (HTML, Javascript CSS). The application of this system enables real-time monitoring of indoor air-dangerous substances. In addition, real-time information on indoor/outdoor detection location and concentration can be sent to the user's mobile in case of a risk situation, which can be expected to help the user respond quickly.

• Journal of the Korean Society for Library and Information Science
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• v.22
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• pp.361-396
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• 1992

The purpose of this study is to verify the correlations between the amount of the online searcher's search experience and their search effect. In order to achieve this purpose, the 28 online searchers working at the chosen libraries and information centers have participated in the study as subjects. The subjects have been classified into the two types of cognitive style by Group Embedded Figure Test. As the result of the GEFT, two groups have been identified: the 15 Field Independance ( FI ) searchers and the 13 Field Dependance ( FD ) searchers. The subject's search experience consists of the 3 elements: disciplinary, training, and working experience. In order to get the data of these empirical elements, a questionnaire have been sent to the 28 subjects. An online searching request form prepared by a practical user was sent to all subjects, who conducted searches of the oversea databases through Dialog to retrieve what was requested. The resultant outcomes were collected and sent back to the user to evaluate relevance and pertinence of the search effect by the individual. In this study, the search effect has been divide into relevance and pertinence. The relevance has been then subdivided into the 3 elements : the number of the relevant documents, recall ratio, and the cost per a relevant document. The relevance has been subdivided into the 3 elements: the number of the pertinent documents, utility ratio, and the cost per a pertinent document. The correlations between the 3 elements of the subject's experience and the 6 elements of the search effect has been analysed in the FI and in the FD searchers separately. At the standard of the 0.01 significance level, findings and conclusions made in the study are summarised as follows : 1. There are strong correlations between the amount of training and the recall ratio, the number of the pertinent documents, and the utility ratio on the part of FI searchers. 2. There are strong correlations between the amount of working experience and the number of the relevant documents, the recall ratio on the part of FD searchers. However, there is also a significant converse correlation between the amount of working experience and the search cost per a pertinent document on the part of FD searchers. 3. The amount of working experience has stronger correlations with the number of the pertinent documents and the utility ratio on the part of FD searchers than the amount of training. 4. There is a strong correlation between the amount of training and the pertinence on both part of FI and FD searchers.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.173-180
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• 2024

We This study aimed to quantitatively analyze the theme of 'libertinage' and the associated issues of reason and emotion in 『Dangerous Liaisons』, a novel considered a masterpiece of libertine literature and an epistolary novel of the 18th century, using digital analysis tools. First, based on the frequency analysis of word usage using Voyant and LIWC 22, we confirmed that libertinage is manifested with keywords such as 'love' and 'time'. With Voyant's 'Contexts' feature, it was found that the letters sent by Valmont to Madame de Tourvel and those sent by Madame de Merteuil both have 'love' as the central theme. However, emotional vocabulary was higher in the former, whereas strategic vocabulary was more prevalent in the latter. Additionally, it was observed that the most frequently used word in the letters sent by Madame de Merteuil is 'time', with a higher frequency than 'love'. Thirdly, using LIWC 22, we measured the analytical thinking and emotional tone of the letters exchanged by the main characters, and analyzed how these values changed according to the chapters. Through these analyses, we confirmed that this novel, alongside Rousseau's "New Eloise," anticipates romanticism by embracing the theme of 'emotion,' which was rejected by 18th-century Enlightenment ideals.

• ETRI Journal
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• v.27 no.1
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• pp.114-117
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• 2005

In this paper, we propose a key management scheme which can provide delivery of the key used to encrypt a digital content from the package server to digital rights management (DRM) clients in a secure manner. The proposed scheme can protect digital content from attacks since an encrypted digital content is sent by a package server and only DRM clients can decrypt the encrypted digital content. It protects the key not only from purchasers but also among the other principals who manage the distribution and license servers.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.825-827
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• 1997

This paper presents a robot which is steered by vision system. The proposed robot system has an AM188ES CPU(5.3 MIPS) and 2DC motors with encoder and turns accurately at any speed and shows a movement like a human controlled car using a steering wheel. To the robot only steering angle value is sent without considering the speed. We present how to control this robot using our real time vision system.

• Journal of Korean Society of Transportation
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• v.8 no.2
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• pp.67-75
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• 1990

This paper treats the problem to schedule for trains with how transit priority so as to maximizing the number that can be sent during given time periods without interfering with the fixed schedule for train with high transit priority in a track. We transform the this problem into Time Expanded Network without traverse time through application of Ford and Fulkerson Model and construct the Enumeration Algorithm for solutions using TENET Generator (TENETGEN). Finally, we compare our algorithm with Dinic's Maximal-Flow Algorithm and examine the avaliability of our procedures in personal computer.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.6
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• pp.624-629
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• 2016

Recently various types of disaster monitoring system using smart-phones are under active studying. In this paper, we propose a system that automatically performs the disaster and fire detection. Additionally we implement the Arduino-based smart image sensor system in the web platform. When a fire is detected, an SMS is sent to the Fire and Disaster Management Agency. In order to improve fire detection probability, we proposed a smart Arduino fire detection sensor simulation which searches the smart sensor inference algorithm using fuzzy rules.

• Management Science and Financial Engineering
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• v.5 no.2
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• pp.25-41
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• 1999

This paper generalizes the classic two-stage multicommodity distribution system design problem to the one that includes plant locations as well as distribution center locations. Accommodating plant location leads to subproblems which are mixed are mixed integer. Hence. no LP-type subproblems are avail-able, and therefore standard Benders decomposition no longer applies. We develop new solution method which combines an integer L-shaped method with Benders decomposition to suit the purpose, and pre-sent the test results.

• Journal of Korea Technology Innovation Society
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• v.6 no.3
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• pp.391-410
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• 2003

Along with the international technology transfer market, as the domestic market grows, more professional technology analysts are needed and it became more necessary to investigate the qualification of those experts to cope with growing market. In this study, the current working condition of those experts is described, qualification system is analyzed and more realistic suggestions on the system to activate the market and to encourage the experts will be introduced. The study was performed based on the questionnaire sent to the person who works in related fields, such as industry, technology transfer center, universities, etc.