• 한국통신학회논문지
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• 제36권6B호
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• pp.697-709
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• 2011

차량과 같은 이동환경에서 무선 인터넷 서비스를 사용할 때, 불필요하게 발생하는 핸드오버는 서비스 품질 저하와 시그널링 오버헤드를 유발하여 실시간 멀티미디어 서비스 제공에 단점으로 작용한다. 본 논문에서는 Mobile Node (MN)가 일정한 이동패턴을 가지고 있을 때, Mobility behavior profile을 이용하여 생성한 DTMC을 이용하여 핸드오버의 발생 횟수를 감소시켜 무선 인터넷 서비스를 향상시킬 수 있는 핸드오버 방법을 제안한다. 기존 핸드오버 방법을 반복적으로 수행하며 Mobility behavior profile을 학습하고, Mobility behavior profile 에 충분한 양이 학습되면 Mobility behavior profile을 이용하여 DTMC의 1-step & 2-step transition probability matrix를 생성한다. 그 이후에는 DTMC의 1-step & 2-step transition probability matrix를 이용하여 핸드오버를 수행하며 Mobility behavior profile을 계속 업데이트한다. 4개의 Mobility model에서의 실험을 통하여 평균 핸드오버 횟수와 평균 RSSI값, 그에 따른 Throughput을 비교한다.

• Journal of Ubiquitous Convergence Technology
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• 제1권1호
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• pp.53-59
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• 2007

This paper proposes a new group mobility model for wireless communication. The mobility model considers the psychological and sociological behavior of each node and the perception of other nodes for describing interactions among a set of nodes. The model assumes no permanent membership of a group, capable of capturing natural behaviors as fork and join. It emulates a cooperative movement pattern observed in mobile ad hoc networks of military operation and campus, in which a set of mobile stations accomplish a cooperative motion affected by the individual behavior as well as a group behavior. The model also employs a physic model to avoid a sudden stopping and a sharping turning.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.79-83
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• 2005

SEA is a useful tool to predict noise and vibration response in high frequency region but has a weak point not to be able to express modal behavior in low frequency region. For a structure with middle subsystem having relatively higher modal density than excited subsystem and receiving subsystem, we studied the possibility that the modal behavior of receiving subsystem can express by considering finite mobility of excited subsystem. For a simply three-coupled beams which is chosen for feasibility study, the response of receiving beam was investigated with varying the length & area moment of inertia of middle beam. In case that the middle beam has relatively higher modal density than exciting beam, the application to finite mobility of excited beam led to express modal behavior of receiving beam relatively well.

• Asia Marketing Journal
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• 제24권4호
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• pp.161-168
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• 2023

With the increased mobility within nations, relocation has become a frequent and regular occurrence in modern life. However, we know little about how residential mobility affects purchase type. How does residential mobility affect our purchase behavior? This research explores the relationship between residential mobility and preference of purchase type, with psychological processes. The study primed participants with either a high or low mobility mindset to investigate the effect of mobility on consumption style in U.S. and South Korean. The results of the study confirm that the consideration of residential mobility shifts consumers' preferences toward material goods and experiences. In addition, results also indicate that the connection between mobility and purchase type was mediated by autonomy and moderated by cultural factor. Lastly, the theoretical and practical implications are covered.

• Journal of Communications and Networks
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• 제17권2호
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• pp.100-109
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• 2015

Mobile phone carriers face challenges from three synergistic dimensions: Wireless, social, and mobile. Despite significant advances that have been made about social networks and human mobility, respectively, our knowledge about the interplay between two layers remains largely limited, partly due to the difficulty in obtaining large-scale datasets that could offer at the same time social and mobile information across a substantial population over an extended period of time. In this paper, we take advantage of a massive, longitudinal mobile phone dataset that consists of human mobility and social network information simultaneously, allowing us to explore the impact of human mobility patterns on the underlying social network. We find that human mobility plays an important role in shaping both local and global structural properties of social network. In contrast to the lack of scale in social networks and human movements, we discovered a characteristic distance in physical space between 10 and 20 km that impacts both local clustering and modular structure in social network. We also find a surprising distinction in trajectory overlap that segments social ties into two categories. Our results are of fundamental relevance to quantitative studies of human behavior, and could serve as the basis of anchoring potential theoretical models of human behavior and building and developing new applications using social and mobile technologies.

• KIEAE Journal
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• 제7권3호
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• pp.49-55
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• 2007

Being different from 20th Century, the right of disabled have attracted much social attention. In reality, the disabled still suffered or not properly respected, thereby a little far less in achieving the quality of life. The purpose of this research was to examine the fitness between the persons with limited mobility and their living environment. Small group workshop with three persons with limited mobility were used for utilized. Living behavior and physical environmental characteristic of dormitory house and interaction between them were identified. Major problem appeared to be accessibility which include the path, room size and furnishing. Even though the dormitory satisfied the government requirement legally. Substantial problems were found because of resident real life. This implied deep consideration beyond Act needed to create a right to robust environment toward persons with limited mobility.

• Journal of Information Processing Systems
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• 제3권1호
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• pp.1-7
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• 2007

In mobile ad hoc networks, an application scenario requires mostly collaborative mobility behavior. The key problem of those applications is scalability with regard to the number of multicast members as well as the number of the multicast group. To enhance scalability with group mobility, we have proposed a multicast protocol based on a new framework for hierarchical multicasting that is suitable for the group mobility model in MANET. The key design goal of this protocol is to solve the problem of reflecting the node's mobility in the overlay multicast tree, the efficient data delivery within the sub-group with group mobility support, and the scalability problem for the large multicast group size. The results obtained through simulations show that our approach supports scalability and efficient data transmission utilizing the characteristic of group mobility.

• 한국심리학회지 : 문화 및 사회문제
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• 제15권2호
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• pp.251-271
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• 2009

본 연구는 이동행동 뿐만 아니라 이동행동에 영향을 미칠 수 있는 심리적·신체적 기제를 포함하여 이동성의 개념을 포괄적으로 측정하였다. 그리고 고령운전자를 대상으로 고령운전자의 이동성이 그들의 삶의 질에 미치는 영향을 살펴보았다. 연구 1에서는 만 20세 이상의 운전자 207명을 대상으로 이동성 질문지를 실시하였다. 요인분석 결과, 이동성은 안전운전능력, 이동감소, 사회활동, 상황적응능력이라는 4개의 요인으로 구성되었다. 연구 2에서는 만 65세 이상의 고령운전자 91명을 대상으로 이동성 질문지와 심리적 안녕감 질문지를 실시하였다. 고령운전자는 일반운전자에 비해 안전운전능력, 상황적응능력이 낮게 나타났으나, 이동감소와 사회활동은 높게 나타났다. 고령운전자의 이동성과 심리적 안녕감 간의 관계를 살펴본 결과, 고령운전자의 이동수준이 높아질수록 더 행복하고 만족스런 삶을 살고 있었다. 특히, 안전운전능력, 사회활동, 상황적응능력의 점수가 높을수록 더 행복하고 만족스런 삶을 살고 있었다. 고령운전자의 이동성이 심리적 안녕감에 미치는 영향을 살펴본 결과, 안전운전능력은 자율성과 자아수용에 영향을 미쳤으며, 이동감소는 자아수용과 긍정적 대인관계에 영향을 미쳤다. 사회활동은 자아수용, 환경지배력, 긍정적 대인관계에 영향을 미치고 있었으며, 상황적응능력은 자율성과 환경지배력에 영향을 미치는 것으로 나타났다.

• 한국IT서비스학회지
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• 제15권3호
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• pp.211-221
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• 2016

The human spatial mobility information is in high demand in various businesses; however, there are only few studies on human mobility because spatio-temporal data is insufficient and difficult to collect. Now with the spread of smartphones and the advent of social networking services, the spatio-temporal data began to occur on a large scale, and the data is available to the public. In this work, we compared the movement behavior of residents and tourists by using geo-tagged tweets which contain location information. We chose Seoul to be the target area for analysis. Various creative concepts and analytical methods are used: grid map concept, cells visited concept, reverse geocoding concept, average activity index, spatial mobility index, and determination of residents and visitors based on the number of days in residence. Conducting a series of analysis, we found significant differences of the movement behavior between local residents and tourists. We also discovered differences in visiting activity according to residential countries and used applications. We expect that findings of this research can provide useful information on tourist development and urban development.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.164.2-164.2
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• 2014

In order to combine advantages of ZnO thin film transistors (TFTs) with a high on-off ratio and graphene TFTs with extremely high carrier mobility, we present a facile methodology for fabricating ZnO thin film/graphene hybrid two-dimensional TFTs. Hybrid TFTs exhibited ambipolar behavior, an outstanding electron mobility of $329.7{\pm}16.9cm^2/V{\cdot}s$, and a high on-off ratio of $10^5$. The ambipolar behavior of the ZnO/graphene hybrid TFT with high electron mobility could be due to the superimposed density of states involving the donor states in the bandgap of ZnO thin films and the linear dispersion of monolayer graphene. We further established an applicable circuit model for understanding the improvement in carrier mobility of ZnO/graphene hybrid TFTs.