• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.05a
• /
• pp.415-418
• /
• 2018

To reduce the flooding overhead of typical AODV, we propose a local flooding initiated by a destination. The proposed routing protocol determines the one-hop neighbor nodes around the shortest path between source and destination by overhearing, and periodically generate flooding at the destination to cope with topology changes. This flooding process involves only one-hop neighbor nodes around the shortest path for reducing the flooding overhead and forms multiple alternate paths around the shortest path. This makes it possible to seamlessly route to the newest shortest path around when the current routing path is disconnected.

• Journal of the Economic Geographical Society of Korea
• /
• v.19 no.1
• /
• pp.68-82
• /
• 2016

Destination choice analysis is an important issue of transportation demand research. The current study analyses the influential factors for university students' trip destination choice. The university students differ from other population groups in many aspects. The study is concerned with shopping, leisure and amusement purposes of trips, other than obligatory trips such as going to school. University students' daily life differs from those of employees and middle and high school students in the sense that a lot of flexible activities are mixed with fixed activities such as work and school attending. A multinomial logit analysis investigates the significance of the impact of a set of variables including residential location, gender and income of the university student. The results show that these variables affect the destination choice of shopping, leisure and amusement. The analysis also provides interesting interpretation of the relationships of the variables with the location choices, which are particularly relevant to the university students.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.18 no.3
• /
• pp.102-112
• /
• 2015

In this paper we propose an application that can help you to find a school near you easily using smart phone GPS capabilities and Google map mounted on Android system. We use a shortest path algorithm to search near destinations. You can take advantage of the developed application when finding public places or destinations. Schools have usually been used as places for disaster evacuation, entrance examination, and qualifying examination. Even though you are not the young who use the smart phone easily, anyone can find a destination school easily with the proposed application of this paper.

• The Monthly Diabetes
• /
• s.223
• /
• pp.8-10
• /
• 2008

자동화와 기계문명의 발달로 현대인들은 점점 걸을 기회가 줄어들고 있다. 자신의 목적지보다 한 정거장 미리 내려걷기, 출근할 때 엘리베이터 대신 계단으로 걷기, 점심 식사 후 회사 주변 산책하기 등 자신의 생활 패턴을 바꾸는 것이 현대인의 건강관리의 지름길이다.

• Journal of the Korean Regional Science Association
• /
• v.37 no.4
• /
• pp.75-93
• /
• 2021

By defining a travel disparity based on the degree to which travelers diversify their destinations, this paper examines how socioeconomic and spatial factors affect the travel disparity among the elderly in Seoul. This paper uses the COVID-19 pandemic as a natural experiment which can bring about different behavioral responses among the older travelers. Using the smart card data, we compare the destination diversification patterns before and after the pandemic. In the early morning(4:30-9:00), the degree of destination diversification varies between the core and the periphery and this trend persists through the pandemic. In the late morning(9:00-12:00), a new trend of disparity appeared after the pandemic. Although those who hold higher socioeconomic status and live closer to the core have a larger range of choices for destinations, the difference of range did not lead to differences in diversification before the pandemic, due to the discretionary nature of the elderly's trip. In contrast, as the elderly were forced to search alternative destinations right after the outbreak of the pandemic, the range of choices became an important factor causing observable differences in destination diversification. The findings suggest that the travel disparity observed during the pandemic is due to the difference in the range of choices by socioeconomic and spatial factors.

• Journal of the Korean Geographical Society
• /
• v.42 no.3 s.120
• /
• pp.421-433
• /
• 2007

The Metropolitan Areas have experienced the phenomenon that some of their peripheral parts emerged as a core business area because of the relocation of residential and economic activities from the central area. An important phenomenon in the spatial transformation of metropolitan area is the weakening of centrality in the center and the increasing strength of centrality in the periphery. This paper examined the changing patterns of spatial interaction in the Seoul Metropolitan area through an analysis on outflow trips. Outflow trip by Seoul decreased in nearby regions and increased in remote regions, however as times goes by, the spatial patterns of the largest outflow trip destination were diversified and the rate of outflow trip to Seoul has decreased in the periphery regions. This research reveals that the most remarkable changes of spatial interactions occurred nearby regions of Seoul and also the changes of outflow trip by Seoul was also distinct. In relation to this, the results arising from the similarity analysis by the variance of trip clearly show the changing spatial patterns of interaction in Yongin, Seoul, Suwon and Hwaseong.

• Korean Journal of Remote Sensing
• /
• v.21 no.4
• /
• pp.329-339
• /
• 2005

In the mobile phone map service there are some restrictions of resolutions and process in terminals. So providing a sketch map is very efficient. This simplifies the map data and increases the understanding of the user. This sketched map marks the starting point and ending point. Then simplifies the surroundings like important roads or building so the user can find his/her way easily. First of all this sketch map service needs a method to simplify the route between starting point and ending point and the surroundings. After that it needs to make the simplified data into a sketch map and suitable to the terminal's resolution. To solve these problems this paper proposes a new method to manifest a sketch map efficiently through a mobile phone. The method, introduced in this paper, is surveyed to have a higher efficiency in data usage compared to the current services available in the market. And also it is examined to have a clear vision in process and easily understandable.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.30 no.1
• /
• pp.29-37
• /
• 2020

Work to improve network throughput has been focused on network coding as the utilization of IoT-based application services increases and network usage increases rapidly. In network coding, nodes transform packets received from neighboring nodes into a combination of encoded packets for transmission and decoding at the destination. This scheme is based on trust among nodes, but in the IoT environment where nodes are free to join, a malicious node can fabricate the packet if it legally participates in the configuration. It is difficult to identify the authenticity of the encoded packet since the packet received at destination is not a single source but a combination of packets generated by several nodes. In this paper, we propose a method to detect "look-like-valid" packets that have been attacked and disguised in packets received at destination, and to identify valid messages in the reconstructions. This method shows that network coding performance is significantly improved because the destination can reconstruct a valid message with only received packets without retransmission with a high probability, despite the presence of disguised packets.

• Proceedings of the Speleological Society Conference
• /
• 1992.07a
• /
• pp.35-39
• /
• 1992

인간은 누구를 막론하고 미지의 지역에 대한 동경과 아울러 그 지역을 방문해 보고자 하는 기본적인 심리를 가지고 있다. 특히 경제적 여유가 신장되고 관광에 대한 일반의 관심이 대단히 높아지면서 우리 주변에 산재하고 있는 관장자원들에 대해 관심을 가지게 된다. 지속적으로 늘어나는 관광객들 개개인의 서로 다른 욕구와 취향, 또는 외부적 여건으로 인한 지각(Perception)의 결과 관광 환경에 대한 상이한 Image가 형성될 것이며, 이는 곧 관광 주체로 하여금 관광지를 선택하게 하는데 있어서 중요한 역할을 하게 될 것이다. 관광지리학 분야에서의 관광자원 또는 Wildness에 대한 인지행동론적 연구는 1960년대의 주관적 환경을 강조하는 행태지리학에서 시작되었으며 관광 목적지에 대한 지각, 인지, Mental Map, 관광행태 등을 포함하고 있다. 이러한 연구들은 대부분 계량적이고 실증적인 시대의 전형적인 산물로서 관광객들의 직접적인 관광형태로 나타나게 하는 의사결정 과정을 중시하는 것이다. 일반적으로 환경에 대한 인지는 과거에 개인의 경험과 현재의 다양한 주변 여건에 의해 크게 달라질 수 있다. 오늘날 인지행태론적 연구는 관광지리학 뿐만 아니라 심리학, 사회학, 인류학 등 사회과학 전반에 걸쳐 연구가 활발하게 이루어 지고 있다. 따라서 본 논고에서는 관광지 및 관광자원에 대한 국내외의 인지행태론적 연구를 검토해 보고 이러한 연구에 많이 이용되고 있는 MDS 분석법을 살펴 보고자 한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.10d
• /
• pp.366-369
• /
• 2006

기존 single sink 센서 네트워크에서의 모든 센서 노드들은 sink로부터 flooding된 질의(query)를 전송 받은 후 센싱 data를 sink로 보냄에 있어서 목적지인 sink 주변 노드의 traffic 집중에 따른 에너지 소비로 인해 전체 네트워크 수명에 영향을 끼쳤다. 이러한 single sink 방식에서의 주변 노드의overhead와 센싱 데이터를 sink로 전달 할 때의 특정 경로상의 노드들의 잔여 에너지량을 고려하여 데이터를 전송하게 함으로써 전체 네트워크 수명을 연장 할 수 있다.