• Proceedings of the Korea Information Processing Society Conference
• /
• 2016.04a
• /
• pp.544-547
• /
• 2016

WBAN (Wirless Body Area Network)은 IEEE 802.15.6에서 정의한 통신 표준으로 인체 내/외부 및 표면에 장착되는 무선 센서 장치들을 통해 의료 및 비의료 서비스를 동시에 제공하는 것을 목표로 한다. 이러한 WBAN은 인체 중심 구성과 네트워크 내부의 이동성 및 네트워크 단위의 이동성을 가지는 특성으로 인해 다수의 WBAN들이 좁은 공간에 공존할 수 있으며, 상호 간섭으로 인해 성능 저하와 같은 문제에 노출된다. 이러한 문제를 해결하기 위해 IEEE 802.15.6에서는 공존 상황을 이동성에 따라 3가지로 세분화 하였으며, 세분화된 각 상황에 적합한 공존성 해결 방안의 가이드라인을 제시하고 있다. 하지만 표준에서는 세분화한 공존 상황을 인지하는 알고리즘과 각 공존성 문제 해결방안의 상세 방안이 결여되어있다. 또한, WBAN의 공존성 문제를 해결하기 위해 제안된 기존의 연구들은 표준에서 정의한 공존상황을 고려하지 않고 있어 추후 표준 기반의 WBAN의 구현시 호환성이 결여된다는 문제점을 가지고 있다. 따라서 WBAN의 공존성 문제 해결에 대한 연구방향의 재조명이 필요한 때 이다. 본 논문에서는 IEEE 802.15.6 표준과 기존의 공존성 문제 해결 방안을 소개하며, 기존 연구의 연구 접근 방법을 분석하고 문제점을 제시한다. 또한, WBAN의 공존성 문제에 대한 새로운 접근 방법과 연구 방향을 제시한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2006.05a
• /
• pp.1015-1018
• /
• 2006

According to the number of the books in the library growing dramatically, dealing with them becomes a serious problem. Especially Plenty of budgets have been consumedin arranging and keeping the books. To solve these confronted problems, RFID technology is researched in this thesis. By utilizing the mobile RFID readers, Book Management System which makes possible to reduce time and cost to input the information of locationand present situation of books in real time is developed. Moreover since the active tag which uses the 900 radio frequency band and mobile RFID reader are used, it is possible to achieve multi-recognizing system.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.2B
• /
• pp.334-344
• /
• 2010

Recently, due to the prevalence of various mobile devices and broadband wireless networks, a significant interests and demands for multimedia streaming services over the Internet have been increasing. However, it is difficult to transmit continuous multimedia stream when mobile terminals are moving. Therefore, in order to deploy mobile IPTV service in the broadband wireless network, efficient wireless resource utilization and seamless QoE (Quality of Experience) offers to the users are an important issue. In this paper, we propose a network based adaptive streaming scheme, called MARC (Mobile Adaptive Rate Control), which controls the quality of the video and rate of the video based on the status of the wireless channel. The proposed scheme uses awareness information of the wireless channel status and controls transmitting streaming video which is suitable for the wireless channel status and mobile station location, in order to provide a seamless video playback for mobile environment in addition to improving the quality of a streaming service. The proposed MARC scheme alleviates the discontinuity of video playback and allocates suitable client buffer in broadband wireless network. Simulation results demonstrate the effectiveness of our proposed scheme.

• Applied Chemistry for Engineering
• /
• v.8 no.4
• /
• pp.694-699
• /
• 1997

Normal-phase HPLC was used to separate the useful phospholipids, PE, PI and PC in soybean lecithin. The mobile phase used in this experiments were haxane, isopropanol and methanol, the gradient mode was applied as the three components could not be separated by the isocratic mode. To find the optimum separation condition, the concentration profiles of effluents were calculated from the plate theory and the capacity factor in step-gradient mode. From the calculated results, PE was separated with hexane/isopropanol/methanol = 90/5/5vol.% in isocratic mode and PI and PC were resolved in the conditions of 10min gradient time and the second mobile phase of hexane/isopropanol/methanol=50/20/30vol.% in step-gradient mode. The agreement between the calculated concentration profile and experimental data was good, so the methodology developed in this work can be used to obtain the optimum separation condition in gradient mode.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.10a
• /
• pp.136-138
• /
• 2015

Recently, with the rapid expansion of the mobile phone, such as the high price of the smartphone is being constantly handset subsidies at issue in the social harm caused by excessive competition in the mobile communications market. In this research, we aim to analyze factors influencing of the policy to subsidy regulatory on decision to continue purchasing intention of consumers. Predictor factors were selected the perceived usefulness, the perceived ease of use and the policy to subsidy regulatory on the previous study. Participants of this study be going to 200 mobile users in Busan Gyeongnam and Jeonbuk province in accordance with convenience sampling. IBM SPSS Statistics 19 were employed for descriptive statistics, Smart PLS(partial least squares) was employed for confirmatory factor analysis and path analysis of casual relationship among variables and effect. This study suggests practical and theoretical implications based on the results.

• International Journal of Highway Engineering
• /
• v.8 no.4 s.30
• /
• pp.1-11
• /
• 2006

Currently, road mobility improved from the National Road Improvement. Nevertheless delineation system is facility that enhanced driver's safety, that was set up often inconsistent or nonexistent over the road exit ramp So it judged functional investigation will be necessary. This study suggested setting type of the delineation system. That was based on a field study and reviews the legal standard of it and considering driver's cognition behavior. For the study, make a 3D-simulation and so could objectively a comparative test. Comparison variable between delineation setting type is selected conspicuity and visibility. Cased that illustrated characteristics of driver's visual cognition behavior. The experiment was used Eye Marker Recorder for measure the gaze frequency more quantitatively and objectively. And used the ANOVA analysis for significance testing between delineation setting type. A significant percent of the conspicuity analyzed types(Safe mark, Obstacle Sign, Warning Light, and Tubular Maker) in road exit ramp for recognize. And gaze frequency that measure of effectiveness of visibility are measured. On the analysis result, the visibility was significance difference between delineation setting type and visibility of types was best.

• Journal of the Economic Geographical Society of Korea
• /
• v.13 no.1
• /
• pp.64-88
• /
• 2010

Rapidly increasing transnational migration can be seen as a typical process which has proceeded under macro-contexts of socio-spatial characters of origin and destination country and their relationships, shaped with global uneven regional development in the process of glocalization and development of transportation and communication on the global level. In order to consider macro-contexts of transnational migration, this paper emphasizes the concept of multicultural space and some key elements implied in it, that is, place, territory, network, scale (suggested by Jessop et al.) and spatial flow and difference. As results of questionnaire analysis of foreign immigrants' recognition of macro-contexts, this paper suggests some findings: that is, a high level of recognition of all types of foreign immigrants on global changes, the most negative recognition of migrant workers among 4 types of foreign immigrants on economic and social conditions of their origin country, a positive recognition of people in all regions of their origin (except few countries such as Japan) on international migration, and a low level of their recognition in all types on S. Korea's characters as their destination country.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.13 no.2
• /
• pp.74-93
• /
• 2010

Nowadays, the navigation system is very popular to general public and the study of landmarks has an important role to develop the cognitive systems for regional navigation. The city image is composed of landmarks that are well-known to regional community and they are the reference frame for place recognition in urban navigation. In general, the case of navigation can be categorized as two kinds. The first is to explore the new region and the second is to navigate the familiar region. In case of latter, the city image has a critical role in place recognition for regional community. Place recognition of a community might be a knowledge-based inference on the basis of city image which is composed of the systematically connected places. In this study, the mental structure of urban image is regarded as a hierarchical knowledge and represents it as domain ontology for the regional navigation of a community. The city image of a community is assumed as the collection of landmarks, which are categorized as anchor, distant and local according to spatial familiarity of community. Representing city image as a regional knowledge using ontology modeling method is an essential step to make the geographical assumption of a regional community explicit and reusable for the regional agents who will provide the regional guide in LBS age.

• Proceedings of the KSCN Conference
• /
• 2003.11a
• /
• pp.1084-1085
• /
• 2003

최근 대학생들은 초등학교 때부터 혹은 중학교 때부터 급식을 받아온 세대로 급식체계에 싫증을 내고 학교 밖의 외부식당으로 눈을 돌리고 있는 세대이다. 또한, 위탁급식전문업체의 대학 내 급식사업 참여와 많은 선행 연구 등을 토대로 여러 면에서 대학 내 구내식당이 개선되고 있으나 아직도 매우 부족한 실정이다. 따라서, 본 연구는 외부식당과의 경쟁으로 현재 급식인원수가 매년 감소하여 운영상의 어려움을 겪고 있는 S 대학 학생식당 고객의 급식소 선택속성에 대한 의견을 조사하고 현재 운영중인 급식소 이외에 추가 설립하고자 하는 식당 신설에 대한 전략을 도출하고자 한다. SPSS통계 package (ver. 11.0)를 활용하여 기술통계(descriptive analysis), 컨조인트 분석 (conjoint analysis)을 실시하였다. 현재 학생식당 이용빈도 감소원인은 ‘음식이 맛이 없어서’가 44.8%, ‘거리가 멀기 때문’이 19.9%로 조사되어, 학생식당의 이용빈도에 가장 큰 영향을 주는 것은 '음식 맛'과 '거리'인 것으로 파악되었으며, 학생식당에 대한 전반적인 만족도는 ‘보통이다’가 37.8%, ‘불만족 한다’가 36%, ‘매우 불만족한다’가 18.4%, ‘만족한다’가 7.8%로 조사되어 응답자의 대부분이 식당에 대해 불만족하고 있었다. 거리에 의해 식당의 이용빈도가 감소하고 있는 것은 현 학생식당의 위치가 강의 동과 먼 거리에 위치하고 있어 강의 동이 밀집해 있는 건물과 근거리에 식당이 개설된다면 이용할 의사가 있는지 여부에 대해 64.7%가 이용하겠다는 의사를 밝혔고 26.1%는 이용하지 않겠다고 응답했다. 따라서, 학생들이 인식하는 적정 거리의 식당 위치를 파악하기 위해 식당으로 이용하는 소요시간에 대해서 조사대상자가 멀다고 인식하는 시간과 가까운 거리라고 인식하는 시간에 대한 조사 결과 가까운 거리로 인지하는 평균 이동소요시간(분)은 5분이었으며 먼 거리로 인지하는 평균이동소요시간은 10.9분으로 적당한 식당의 위치는 S~10분내의 거리로 9분 30초의 거리에 식당이 위치하면 학생들의 이용률을 극대화시킬 수 있을 거라 사료된다. 사전 대면면접을 통해 가격, 소요시간, 음식의 맛으로 선정된 속성과 각 속성별 수준을 활용한 컨조인트 분석 실시하여 도출된 학생들의 급식소 선택 시 중요하게 인식하는 속성은 가격대, 소요 시간, 음식 맛 순으로 나타났으며, 각각의 중요도는 가격이 65.42%, 소요시간인 24.76%, 음식의 맛이 9.82%였다. 즉, 학생들은 학생식당의 서비스 품질 속성 중에서 상대적으로 식사 가격을 가장 중요하기 생각하는 것으로 나타났고, 다음으로는 식사를 하기 위해 식당까지 가는데 소요되는 시간, 음식의 맛을 중요하게 생각하는 것으로 분석되었다. 컨조인트 분석결과 조사대상자가 가장 선호하는 대학 식당으로는 이동하는데 6-10분이 소요되는 거리에 위치한 식당으로 2,100-2,500원 정도의 가격대로 맛있고 깔끔한 식당을 가장 선호하는 것으로 조사되었다. 따라서, 현재 운영중인 학생식당이 모두 1,800원의 단일 식단가로 운영되고 있는 점을 감안하여 학생식당을 신설할 경우에는 이동하는데 10분 이상 소요되지 않는 장소에 가격대는 현재보다 더 높은 2,000-2,500원의 가격대에서 맛있고 깔끔한 현재와는 차별화 된 일품메뉴 위주의 식단의 학생식당을 신설하는 것이 바람직할 것으로 사료된다.

• Journal of Internet Computing and Services
• /
• v.24 no.6
• /
• pp.81-89
• /
• 2023

In modern society, blind people face difficulties in navigating common environments such as sidewalks, elevators, and crosswalks. Research has been conducted to alleviate these inconveniences for the visually impaired through the use of visual and audio aids. However, such research often encounters limitations when it comes to practical implementation due to the high cost of wearable devices, high-performance CCTV systems, and voice sensors. In this paper, we propose an artificial intelligence fusion algorithm that utilizes low-cost video sensors integrated into smartphones to help blind people safely navigate their surroundings during walking. The proposed algorithm combines motion capture and object detection algorithms to detect moving people and various obstacles encountered during walking. We employed the MediaPipe library for motion capture to model and detect surrounding pedestrians during motion. Additionally, we used object detection algorithms to model and detect various obstacles that can occur during walking on sidewalks. Through experimentation, we validated the performance of the artificial intelligence fusion algorithm, achieving accuracy of 0.92, precision of 0.91, recall of 0.99, and an F1 score of 0.95. This research can assist blind people in navigating through obstacles such as bollards, shared scooters, and vehicles encountered during walking, thereby enhancing their mobility and safety.