• 인지과학
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• 제19권2호
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• pp.107-123
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• 2008

대화 시스템에 관한 기존 연구는 실용시스템을 위한 연구와 대화 현상 이해에 중심을 둔 연구로 나눌 수 있다. 전자는 실제 환경에서 강인한 성능을 유지하는 것에 초점을 두고 있다. 하지만 매우 제한적인 상황에서만 성능을 보장할 수 있으며 다양한 형태의 대화를 적용하기 어렵다. 후자의 연구에서는 대표적으로 계획기반 모델(plan-based model)이 제안되었는데, 이 모델은 복잡한 대화 구조를 모델링(modeling)할 수 있으며, 다양한 현상에서의 사용자 목적 추론이 가능하다. 하지만 계획기반 모델은 초기 설계가 어렵고 실용적인 대화 시스템 구축에 있어서 시스템 응답을 생성하기 위한 상호작용 모델로의 확장이 매우 어렵기 때문에 실용시스템으로의 적용이 쉽지 않다. 본 연구는 이러한 계획기반 모델의 단점을 보완하고 실용적인 대화 시스템을 구축하기 위하여, 시스템 응답을 위한 확인 대화 전략과 담화스택(discourse stack)을 계획기반 대화 모델에 적용함으로써 효율적인 응답을 생성할 수 있는 새로운 기법을 제안한다.

• 디지털산업정보학회논문지
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• 제11권4호
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• pp.113-127
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• 2015

An interface in smart device environment is changing to TUI(touch user interface) environment where a system is being controlled by physical touch, differently from a system controlled through conventional mouse and keyboard. What is more important than anything else in this TUI environment is to implement interface in consideration of learn ability and cognitive constructivism according to user's experience. Therefore, now is the time when it is necessary to carry out various studies on smart content design process going a step farther together with discussing the details of user's experience factor. Hence, this study was intended to look into what effect a user's experiential traits had on the production of contents for the purpose of measures for improving TUI user satisfaction in order to effectively realize contents in smart environment. Results were yielded by using a statistical empirical analysis such as cross-tabulation analysis according to important variable and user, paired t-test, multiple response analysis, and preference frequency analysis of user preference on the basis of a survey. As a result, a system was presented for implementing DFSS(Design For Six Sigma) process. TUI experience factor can be divided into direct habitual experience, direct learning experience, indirect habitual experience, and indirect learning experience. And in the results of study, it was possible to find that the important variables of this study had a positive effect on the improvement of use satisfaction with contents on the whole according to the user convenience of smart contents. This study is expected to have a positive effect on efficient smart device-based contents production by providing objective information according to empirical analysis to smart media-based developer and designer and presenting a model for improving the changed TUI usability.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권6호
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• pp.2709-2734
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• 2020

The growing demand to make wireless data services 5G compatible has necessitated the development of an energy-efficient approach for an effective new wireless environment. In this paper, we first propose a cognitive sensor node (CSN) based game theory for deriving energy via a primary user-transmitted radio frequency signal. Cognitive users' time was segmented into three phases based on a time switching protocol: energy harvest, spectrum sensing and data transmission. The proposed model chooses the optimal energy-harvesting phase as the effected factor. We further propose a distributed energy-harvesting model as a utility function via pricing techniques. The model is a non-cooperative game where players can increase their net benefit in a selfish manner. Here, the price is described as a function pertaining to transmit power, which proves that the proposed energy harvest game includes Nash Equilibrium and is also unique. The best response algorithm is used to achieve the green connection between players. As a result, the results obtained from the proposed model and algorithm show the advantages as well as the effectiveness of the proposed study. Moreover, energy consumption was reduced significantly (12%) compared to the benchmark algorithm because the proposed algorithm succeeded in delivering energy in micro which is much better compared to previous studies. Considering the reduction and improvement in power consumption, we could say the proposed model is suitable for the next wireless environment represented in 5G.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권7호
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• pp.3414-3434
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• 2016

Classical key generation is complicated to update and key distribution generally requires fixed infrastructures. In order to eliminate these restrictions researchers have focused much attention on physical-layer (PHY-layer) based key generation methods. In this paper, we present a PHY-layer fingerprints based fuzzy key generation scheme, which works to prevent primary user emulation (PUE) attacks and spectrum sensing data falsification (SSDF) attacks, with multi-node collaborative defense strategies. We also propose two algorithms, the EA algorithm and the TA algorithm, to defend against eavesdropping attacks and tampering attacks in mobile cognitive radio networks (CRNs). We give security analyses of these algorithms in both the spatial and temporal domains, and prove the upper bound of the entropy loss in theory. We present a simulation result based on a MIMO-OFDM communication system which shows that the channel response characteristics received by legitimates tend to be consistent and phase characteristics are much more robust for key generation in mobile CRNs. In addition, NIST statistical tests show that the generated key in our proposed approach is secure and reliable.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권4호
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• pp.1192-1207
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• 2014

Dynamic spectrum sharing is a key technology to improve spectrum utilization in wireless networks. The elastic spectrum management provides a new opportunity for licensed primary users and unlicensed secondary users to efficiently utilize the scarce wireless resource. In this paper, we present a game-theoretic framework for dynamic spectrum allocation where the primary users rent the unutilized spectrum to the secondary users for a monetary profit. In reality, due to the ON-OFF behavior of the primary user, the quantity of spectrum that can be opportunistically shared by the secondary users is limited. We model this situation with the renewal theory and formulate the spectrum pricing scheme with the Bertrand game, taking into account the scarcity of the spectrum. By the Nash-equilibrium pricing scheme, each player in the game continually converges to a strategy that maximizes its own profit. We also investigate the impact of several properties, including channel quality and spectrum substitutability. Based on the equilibrium analysis, we finally propose a decentralized algorithm that leads the primary users to the Nash-equilibrium, called DST. The stability of the proposed algorithm in terms of convergence to the Nash equilibrium is also studied.

• 한국의류학회지
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• 제47권2호
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• pp.323-336
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• 2023

In the 21st century, fashion films are frequently used throughout the fashion industry. In particular, as videos have become an essential element and a communication tool of social media, they are becoming even more important in the world of fashion. In this study, different types of short-length fashion films (< 0:60) in current use were derived, and the effects of on the cognitive and emotional responses of users were analyzed using electroencephalogram(EEG) findings. EEG measurements were performed using Epoc+ on 31 healthy women aged 20-29 years after viewing six types of fashion films[fiction/well-made, fiction/user generated content(UGC), documentary/well-made, documentary/UGC, art/well-made, and art/UGC] in random order. The results demonstrate differences among four types of films. Specifically, alpha waves in the frontal lobe decreased more while watching documentary/UGC films than while watching art/well-made films. Gamma waves in the temporal lobe decreased more while watching fiction/well-made films than while watching documentary/UGC films. Furthermore, theta waves in the occipital lobe increased more while watching fiction/well-made films than while watching art/UGC films. These findings suggest that different types of fashion films can stimulate different parts of the brain that process thinking, cognition, emotion, and visual and auditory information and consequently evoke emotional responses.

• Journal of Information Science Theory and Practice
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• 제1권3호
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• pp.12-32
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• 2013

The paper introduces the research area of interactive information retrieval (IIR) from a historical point of view. Further, the focus here is on evaluation, because much research in IR deals with IR evaluation methodology due to the core research interest in IR performance, system interaction and satisfaction with retrieved information. In order to position IIR evaluation, the Cranfield model and the series of tests that led to the Cranfield model are outlined. Three iconic user-oriented studies and projects that all have contributed to how IIR is perceived and understood today are presented: The MEDLARS test, the Book House fiction retrieval system, and the OKAPI project. On this basis the call for alternative IIR evaluation approaches motivated by the three revolutions (the cognitive, the relevance, and the interactive revolutions) put forward by Robertson & Hancock-Beaulieu (1992) is presented. As a response to this call the 'IIR evaluation model' by Borlund (e.g., 2003a) is introduced. The objective of the IIR evaluation model is to facilitate IIR evaluation as close as possible to actual information searching and IR processes, though still in a relatively controlled evaluation environment, in which the test instrument of a simulated work task situation plays a central part.

• Asia pacific journal of information systems
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• 제20권3호
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• pp.167-190
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• 2010

The research conducted here focuses on the effect of factors that affect the behavior of UCC (User Created Content) website users, other than user's rational recognition of how useful a UCC website can be. Most discussions in the existing literature on information systems have focused on users' evaluation how a UCC website can help to attain the users' own goals. However, there are other factors and this research pays attention to an individual's 'personality,' which is stable and biological in nature. Specifically, I have noted here that 'extroversion' and 'neuroticism,' the two common personality factors presented in Eysenck's most representative 'EPQ Model' and 'Big Five Model,' are the two personality factors that affect a site's 'usefulness,' by this I mean how useful does the user consider the website and its content. How useful a site is considered by the user is the other factor that has been regarded as the antecedent factor that influences the adoption of information systems in the existing MIS (Management Information System) research. Secondly, as using or creating a UCC website does not guarantee the user's or the creator's extrinsic motivation, unlike when using the information system within an organization, there is a greater likelihood that the increase in user's activities in relation to a UCC website is motivated by emotional factors rather than rational factors. Thus, I have decided to include the relationship between an individual's personality and what they find pleasurable in the research model. Thirdly, when based on the S-O-R Paradigm of Mehrabian and Russell, the two cognitive factors and emotional factors are finally affected by stimulus, and thus these factors ultimately have an effect on an individual's respondent behavior. Therefore, this research has presented an assumption that the recognition of how useful the site and content is and what emotional pleasure it provides will finally affect the behavior of the UCC website users. Finally, the relationship between the recognition of how useful a site is and how pleasurable it is to useand UCC usage may differ depending on certain situational conditions. In other words, the relationship between the three factors may vary according to how much users are involved in the creation of the website content. Creation thus emerges as the keyword of UCC. I analyzed the above relationships through the moderating variable of the user's involvement in the creation of the site. The research result shows the following: When it comes to the relationship between an individual's personality and what they find pleasurable it is extroverted users who have a greater likelihood to feel pleasure when using a UCC website, as was expected in this research. This in turn leads to a more active usage of the UCC web site because a person who is an extrovert likes to spend time on activities with other people, is sensitive to new experiences and stimuli and thus actively responds to these. An extroverted person accepts new UCC activities as part of his/her social life, rather than getting away from this new UCC environment. This is represented by the term 'Foxonomy' where the users meet a variety of users from all over the world and contact new types of content created by these users. However, neuroticism creates the opposite situation to that created by extroversion. The representative symptoms of neuroticism are instability, stress, and tension. These dispositions are more closely related to stress caused by a new environment rather than this creatingcuriosity or pleasure. Thus, neurotic persons have an uneasy feeling and will eventually avoid the situation where their own or others' daily lives are frequently exposed to the open web environment, this eventually makes them have a negative attitude towards the web environment. When it comes to an individual's personality and how useful site is, the two personality factors of extroversion and neuroticism both have a positive relationship with the recognition of how useful the site and its content is. The positive, curious, and social dispositions of extroverted persons tend to make them consider the future usefulness and possibilities of a new type of information system, or website, based on their positive attitude, which has a significant influence on the recognition of how useful these UCC sites are. Neuroticism also favorably affects how useful a UCC website can be through a different mechanism from that of extroversion. As the neurotic persons tend to feel uneasy and have much doubt about a new type of information system, they actively explore its usefulness in order to relieve their uncomfortable feelings. In other words, neurotic persons seek out how useful a site can be in order to secure their own stable feelings. Meanwhile, extroverted persons explore how useful a site can be because of their positive attitude and curiosity. As a lot of MIS research has revealed that the recognition of how useful a site can be and how pleasurable it can be to use have been proven to have a significant effect on UCC activity. However, the relationship between these factors reveals different aspects based on the user's involvement in creation. This factor of creationgauges the interest of users in the creation of UCC contents. Involvement is a variable that shows the level of an individual's mental effort in creating UCC contents. When a user is highly involved in the creation process and makes an enormous effort to create UCC content (classed a part of a high-involvement group), their own pleasure and recognition of how useful the site is have a significantly higher effect on the future usage of the UCC contents, more significantly than the users who sit back and just retrieve the UCC content created by others. The cognitive and emotional response of those in the low-involvement group is unlikely to last long,even if they recognize the contents of a UCC website is pleasurable and useful to them. However, the high-involvement group tends to participate in the creation and the usage of UCC more favorably, connecting the experience with their own goals. In this respect, this research presents an answer to the question; why so many people are participating in the usage of UCC, the representative form of the Web 2.0 that has drastically involved more and more people in the creation of UCC, even if they cannot gain any monetary or social compensation. Neither information system nor a website can succeed unless it secures a certain level of user base. Moreover, it cannot be further developed when the reasons, or problems, for people's participation are not suitably explored, even if it has a certain user base. Thus, what is significant in this research is that it has studied users' respondent behavior based on an individual's innate personality, emotion, and cognitive interaction, unlike the existing research that has focused on 'compensation' to explain users' participation with the UCC website. There are also limitations in this research. Firstly, I divided an individual's personality into extroversion and neuroticism; however, there are many other personal factors such as neuro-psychiatricism, which also needs to be analyzed for its influence on UCC activities. Secondly, as a UCC website comes in many types such as multimedia, Wikis, and podcasting, these types need to be included as a sub-category of the UCC websites and their relationship with personality, emotion, cognition, and behavior also needs to be analyzed.

• 인터넷정보학회논문지
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• 제25권2호
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• pp.57-67
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• 2024

사용자가 제스처를 통해 입력을 할 수 있는 방안들 중에서 근전도(EMG, Electromyography)를 통한 제스처 인식은 근육 내 작은 전극을 통해 사용자의 움직임을 감지하고 이를 입력 방법으로 사용할 수 있는 방법이다. EMG 데이터를 통해 사용자 제스처를 분류하기 위해서는 사용자로부터 수집된 EMG Raw 데이터를 머신러닝으로 학습하여야 하는데 이를 위해서는 EMG 데이터를 전처리 과정을 통해 특징을 추출하여야 한다. EMG 특성은 IEMG(Integrated EMG), MAV(Mean Absolute Value), SSI(Simple Sqaure Integral), VAR(VARiance), RMS(Root Mean Square) 등과 같은 수식을 통해서 나타낼 수 있다. 또한, 제스처를 입력으로 사용하기 위해서는 사용자가 입력하는 데 필요한 지각, 인지, 반응에 필요한 시간을 기준으로 제스처 분류가 가능한 시간을 알아내야 한다. 이를 위해 최대 1,000ms에서 최소 100ms까지 세그먼트 사이즈를 변화시켜 특징을 추출 후 제스처 분류가 가능한 세그먼트 사이즈를 찾아낸다. 특히 데이터 학습은 overlapped segmentation 방법을 통해 데이터와 데이터 사이 간격을 줄여 학습 데이터 개수를 늘린다. 이를 통해 KNN, SVC, RF, XGBoost 4가지 머신러닝 방식을 통해 이를 학습하고 결과를 도출한다. 실험 결과 실시간으로 사용자의 제스처 입력이 가능한 최대 세그먼트 사이즈인 200ms에서 KNN, SVC, RF, XGboost 4가지 모든 모델에서 96% 이상의 정확도를 도출하였다.

• 디자인학연구
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• 제16권2호
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• pp.415-424
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• 2003

사람들은 기억해야할 정보를 머리 속에만 저장하지는 않는다 그러한 정보를 사물에 저장할 수 도 있는데 노만은 이를 세상 속 지식이라고 부른다. 가장 보편적이면서 일반적으로 정보를 사물에 저장하는 방식은 이름표를 부착하는 것이다. 4구 가스레인지에 있어서도 마찬가지로 사용자는 버너와 스위치간의 관계를 기억할 필요 없이 이름표를 보고 이들 관계에 대한 개념모형을 만들도록 가스레인지는 사용자에게 요구하고 있다. 하지만 사용자가 일일이 이름표를 보고 스위치를 조작하는 것은 인지적 스트레스일 것이다. 노만은 이러한 문제를 해결하고자 버너와 스위치가 자연적으로 대응되도록 공간적 유사성을 통한 방법을 제시하였다. 그러나 그의 방법은 현실적으로 주방의 구조에 잘 부합할 수 없어 사용되기가 힘들다. 본 연구에서는 이러한 문제를 해결할 방법으로 칼라코딩을 제안하였다. 버너와 스위치를 칼라로 코딩하면 자연적인 대응이 이루어질 것이라는 관점에서 일반적인 가스레인지를 사용하는 집단과 칼라코딩 된 가스레인지를 사용하는 집단을 자극에 대한 정확성과 반응시간을 기준으로 실험하였다. 실험결과 두 집단간의 과제에 대한 정확도의 차이(f(1,38)=17.892, p<.01)와 반응시간(F(1,38)=6.726 p<.05)의 차이가 유의미하여 칼라코딩의 효과가 있음이 증명되었다. 본 연구를 통해서 칼라코딩이 디자인과정에서 인지적 분류가 중요한 제품들의 디자인에 효과적으로 사용될 수 있음을 제시하고 있다.