• Resources Recycling
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• v.28 no.1
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• pp.62-72
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• 2019

Generally, $H_2SO_4$ and Cu metal are used as raw materials for producing copper sulfate. The study relates to a method for producing copper sulfate using electrowinning from a waste solution of copper chloride. Uses are used for copper plating for industry, plating, feed, agriculture, electronic grade PCB. Conventional methods for producing copper sulfate have a problem of a large amount of waste water and a high energy cost. A study on the production method of copper sulfate ($CuSO_4$), which is the most used among copper (Cu) compounds, has a low process operation ratio, a small amount of waste water, and a simple manufacturing process. It is easy to remove Na, Ca, Mg, and Al as impurities by using a cationic membrane. At the same time, high purity copper powder could be recovered by an electrowinninng method. Using the recovered copper powder, high purity copper sulfate could be produced.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.2
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• pp.172-178
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• 2020

In order to recommend contents, the company generally uses collaborative filtering that takes into account both user preferences and video (item) similarities. Such services are primarily intended to facilitate user convenience by leveraging personal preferences such as user search keywords and viewing time. It will also be ranked around the keywords specified in the video. However, there is a limit to analyzing video similarities using limited keywords. In such cases, the problem becomes serious if the specified keyword does not properly reflect the item. In this paper, I would like to propose a system that identifies the characteristics of a video as it is by the system without human intervention, and analyzes and recommends similarities between videos. The proposed system analyzes similarities by taking into account all words (keywords) that have different meanings from training videos, and in such cases, the methods handled by big data clusters are applied because of the large scale of data and operations.

• Journal of Internet of Things and Convergence
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• v.7 no.2
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• pp.41-45
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• 2021

This paper proposes a video content delivery scheme for vehicles. Today, we spend a lot of time commuting to work in vehicles such as trains and cars. In addition, the number of users who enjoy video content such as YouTube and Netflix in order to appease the boredom in the vehicle is increasing rapidly. Video content requires a larger amount of data usage than text-based content. Hence, the user's mobile communication data usage increases rapidly along with the cost. The proposed video content delivery scheme downloads a lot of video content in advance when the vehicle is in a free Wi-Fi area. In this way, it is possible to play video content in a vehicle at a low cost. It is expected that the proposed scheme can be applied to the Internet of Things(IoT) for moving objects.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.29-35
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• 2023

This paper makes it possible to search videos based on sentence by improving the previous research which automatically generates rich metadata from videos and searches videos by key words. For search by sentence, morphemes are analyzed for each sentence, keywords are extracted, weights are assigned to each keyword, and some videos are recommended by applying a ranking algorithm developed in the previous research. In order to evaluate performance of video search in this paper, a sufficient amount of videos and sufficient number of user experiences are re required. However, in the current situation where these are insufficient, three indirect evaluation methods were used: evaluation of overall user satisfaction, comparison of recommendation scores and user satisfaction, and evaluation of user satisfaction by video categories. As a result of performance evaluation, it was shown that the rich metadata construction and video recommendation implementation in this paper give users high search satisfaction.

• Journal of Digital Convergence
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• v.20 no.1
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• pp.317-326
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• 2022

This study is an explorer study to investigate the experience of long term care hospital workers on the sexual behaviors of the elderly. The data were collected from August to October in 2019. The depth interview was implemented with using the semi structured questionnaires. The interview data collected from the participants were analyzed with using qualitative thematic analysis methods. The experience of long term care hospital workers regarding the elderly's sexual behaviors consisted of ten sub-categorized themes from the significant statements and was categorized into following four themes; 'Negative feelings related with elderlys' sexual behaviors', 'Difficulty of maintaining caring roles', 'Recognizing the absence of care for elderlys' sexual behavior', 'Accepting the therapeutic roles for elderlys' sexual behavior'. The findings could be the basic data for developing educational programs that help the long term care hospital workers understand the sexual behavior of the elderly.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.331-332
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• 2022

After the Great East Japan Earthquake, reports and books that compiled the testimonies of the victims were published and the situation of the evacuation at that time became known. However, there is very little information on the evacuation situation of children among these data, and it is not fully known what actions the children took and how they evacuated due to an earthquake or tsunami. The purpose of this study is to analyze and examine children's evacuation behavior in the Great East Japan Earthquake, and to predict children's evacuation behavior for future disasters.

• 방재와보험
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• s.110
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• pp.56-61
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• 2005

쌀쌀한 찬바람에 어느덧 겨울이 성큼 다가왔다. 전체 화재의 상당부분을 차지하는 동절기 화재사고는 다른 계절에 비해 상대적으로 화기를 필요 이상으로 많이 사용하게 되고 추운날씨로 인해 화재예방 점검을 소홀히 하기 때문이다. 부주의로 인하여 발생되는 동절기 화재사고의 사례을 살펴봄으로써 화재에 대한 경각심을 새롭게 갖는 한편, 그에 따른 문제점과 대책을 알아 보고자 한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.167-173
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• 2002

본 논문에서는 동영상 신호에 대한 워터마킹 알고리즘의 관점에서 워터마킹 성능, 부호화성능, 실시간 구현 등의 요구조건 사이의 관계를 살펴보고, 모의실험을 바탕으로 재부호화시의 강인성, 필터링공격에 대한 강인성 등 동영상 워터마킹 방법에 대해 성능을 분석한다.

• Venture DIGEST
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• s.61
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• pp.22-23
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• 2004

독일, 영국에 이어 유럽 마지막 편으로 프랑스와 동유럽의 IT현황을 준비하였다. 프랑스는 세계4위의 경제강국으로 유럽국가 중 GDP규모 1위를 지키고 있고, 동유럽국가들은 EU진출을 계기로 새롭게 주목받고 있다. 이들 나라들의 정보통신 현황을 살펴보고 유럽진출의 방안을 다각도로 모색해보자.

• Journal of the korean Society of Automotive Engineers
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• v.25 no.3
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• pp.25-29
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• 2003

한국타이어 동역학연구팀은 약 10여년전 처음 독립부서로 만들어져 현재 실차 시험 전문 드라이버들을 포함해서 연구인력만 약 20여명 되는 연구팀으로 발전했다. 동역학연구팀에서 수행되고 있는 업무는 성능 별로 크게 쏠림, 조종안정성, 제동, 승차감 등으로 나뉠 수 있으나 이번 기회에는 주로 조종안정성에 대한 연구활동에 대해 소개하고자 한다.