• Title/Summary/Keyword: local distance

Search Result 1,122, Processing Time 0.031 seconds

Reference Node Selection Scheme for Estimating Relative Locations of Mobile Robots (이동 로봇의 상대위치 추정을 위한 기준노드 선택 기법)

  • Ha, Taejin;Kim, Sunyong;Park, Sun Young;Kwon, Daehoon;Ham, Jaehyun;Lim, Hyuk
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.19 no.4
    • /
    • pp.508-516
    • /
    • 2016
  • When GPS signals are not available, a relative localization can be alternatively used to represent the topological relationship between mobile nodes. A relative location map of a network can be constructed by using the distance information between all the pairs of nodes in the network. If a network is large, a number of small local maps are individually constructed and are merged to obtain the whole map. However, this approach may result in a high computation and communication overhead. In this paper, we propose a reference-node selection scheme for relative localization map construction, which chooses a subset of nodes as a reference node that is supposed to construct local maps. The scheme is a greedy algorithm that iteratively chooses nodes with high degree as a reference node until the chosen local maps are successfully merged with a sufficient number of common nodes between nearby local maps. The simulation results indicate that the proposed scheme achieves higher localization accuracy with a reduced computational overhead.

Real-time Small Target Detection using Local Contrast Difference Measure at Predictive Candidate Region (예측 후보 영역에서의 지역적 대비 차 계산 방법을 활용한 실시간 소형 표적 검출)

  • Ban, Jong-Hee;Wang, Ji-Hyeun;Lee, Donghwa;Yoo, Joon-Hyuk;Yoo, Seong-eun
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.22 no.2
    • /
    • pp.1-13
    • /
    • 2017
  • In This Paper, we find the Target Candidate Region and the Location of the Candidate Region by Performing the Morphological Difference Calculation and Pixel Labeling for Robust Small Target Detection in Infrared Image with low SNR. Conventional Target Detection Methods based on Morphology Algorithms are low in Detection Accuracy due to their Vulnerability to Clutter in Infrared Images. To Address the Problem, Target Signal Enhancement and Background Clutter Suppression are Achieved Simultaneously by Combining Moravec Algorithm and LCM (Local Contrast Measure) Algorithm to Classify the Target and Noise in the Candidate Region. In Addition, the Proposed Algorithm can Efficiently Detect Multiple Targets by Solving the Problem of Limited Detection of a Single Target in the Target Detection method using the Morphology Operation and the Gaussian Distance Function Which were Developed for Real time Target Detection.

A Study of Safety Evaluation Based on the Road closure Simulation, and on the Isolation Risk in Times of Disaster (재해시 위험가능성과 도로폐쇄시뮬레이션에 의한 방재안전성에 관한 연구 - 일본 오이타현 사이키시를 대상으로 -)

  • Kim, Daeill;Park, Sungchan;Go, Jooyeon;Yeom, Chunho
    • Journal of the Korean Society of Safety
    • /
    • v.35 no.2
    • /
    • pp.84-93
    • /
    • 2020
  • In recent years, the scale of damage from disasters such as earthquakes and large-scale fires and floods that are occurring in Korea is increasing. Accordingly, interest in urban disaster prevention that combines living infrastructure such as roads and parks is boosting, and it is urgent to prepare measures to reduce the damage scale of local cities. The purpose of this study is to derive implications for disaster prevention measures in areas where disaster prevention safety of local cities is weak through examples of disaster prevention safety of local cities in case of disaster. To this end, this study analyzed the regional characteristics, current status, and disaster prevention problems of regional cities in Japan, and selected disaster-vulnerable areas, and considered the distance relationship between disaster prevention bases through road network analysis. In addition, road closure simulation using ArcGIS Network Analyst was conducted to analyze disaster prevention safety in the area. As a result, the situation of the village which has a high possibility of isolation by natural disasters was grasped in advance. Through this, the suburbs confirmed the necessity of supplementing the disaster prevention function through transportation maintenance such as forest roads, and it was found that the city needs to prepare a risk management system. Furthermore, this study suggests the need for research on areas with a high possibility of isolation, especially in areas where disaster prevention functions are weak in local cities in case of disaster, and shows countermeasures for disaster prevention measures and resident education.

A Study on the Space Planning for Unified School and Appropriate Utilization of Closed School following the Merger and Abolition of Small Schools in Rural Area (소규모학교 통폐합에 따른 통합초등학교의 공간구성 및 폐교 활용에 관한 연구)

  • Lee, Hwa-Ryong;Rhew, Choon-Geun;Oh, Se-Hee;Park, So-Young
    • Journal of the Korean Institute of Educational Facilities
    • /
    • v.19 no.3
    • /
    • pp.21-31
    • /
    • 2012
  • According to the decrease in birth rate and reduction of population in rural area, primary schools have brought about many problems for decrease of number of student, and environment of education have became deteriorated. Accordingly, primary schools be required improvement, and it should be altered placement of schools because it change number of student, distance and time of attending school, and formation of school zone are changed by alternating of human and physical environment. Merger and abolition of primary school is inevitable for change of placement standard to primary school and qualitative improvement of environment of education in rural area. This study suggests the effective space planning methods for unified school and appropriate utilization alternatives for closed school following after the merger and abolition of small rural schools. In doing so, it explores the present models of merger and abolition through analysis of all sort of actual condition and the possibilities for various utilizations of the abolished schools. It proposes a classroom-operation type fused the comprehensive class and departmental class system for merged primary schools in rural area. It also suggests the re-use methods of closed school facilities for students and community. Finally, it emphasizes that in order to success the policy of the merger and abolition of small schools, it be attributed to the social-cultural environment based on local residents and community and required provision of a variety of utilization plans reflecting local specifics and guarantee of local residents' participation and selection.

Development of Potential Function Based Path Planning Algorithm for Mobile Robot

  • Lee, Sang-Il;Kim, Myun-Hee;Oh, Kwang-Seuk;Lee, Sang-Ryong
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.2325-2330
    • /
    • 2005
  • A potential field method for solving the problem of path planning based on global and local information for a mobile robot moving among a set of stationary obstacles is described. The concept of various method used path planning is used design a planning strategy. A real human living area is constructed by many moving and imminence obstacles. Home service mobile robot must avoid many obstacles instantly. A path that safe and attraction towards the goal is chosen. The potential function depends on distance from the goal and heuristic function relies on surrounding environments. Three additional combined methods are proposed to apply to human living area, calibration robots position by measured surrounding environment and adapted home service robots. In this work, we proposed the application of various path planning theory to real area, human living. First, we consider potential field method. Potential field method is attractive method, but that method has great problem called local minimum. So we proposed intermediate point in real area. Intermediate point was set in doorframe and between walls there is connect other room or other area. Intermediate point is very efficiency in computing path. That point is able to smaller area, area divided by intermediate point line. The important idea is intermediate point is permanent point until destruction house or apartment house. Second step is move robot with sensing on front of mobile robot. With sensing, mobile robot recognize obstacle and judge moving obstacle. If mobile robot is reach the intermediate point, robot sensing the surround of point. Mobile robot has data about intermediate point, so mobile robot is able to calibration robots position and direction. Third, we gave uncertainty to robot and obstacles. Because, mobile robot was motion and sensing ability is not enough to control. Robot and obstacle have uncertainty. So, mobile robot planed safe path planning to collision free. Finally, escape local minimum, that has possibility occur robot do not work. Local minimum problem solved by virtual obstacle method. Next is some supposition in real living area.

  • PDF

Phenomenological Study of Skin Scuba Participants in Busan Region (부산지역 스킨스쿠버 참여자의 현상학적 연구)

  • JANG, Jae-Yong
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.29 no.1
    • /
    • pp.148-157
    • /
    • 2017
  • This study has studied the phenomenon exclusive to the activity of skin scuba among marine sports in Busan region, and such empirical studies are for the development of skin scuba, and even of the entire marine sports, and in order to achieve such objective, the study method centered around qualitative study method of in-depth interview, participatory observation, and documentation study, the results of which are as follows. First is the advantage of the local environment as an open-water location. This study area has beaches of pebbles, and the underwater is also comprised of pebbles up to a certain distance, securing a superior underwater visibility compared to the sand of other Busan regions, and such local environment is thought to be an advantage of skin scuba activity. Second is the satisfaction of accessibility. This study area had an advantage in participant accessibility, which is thought to act as a good strength for the marine sports development of this area in the future. Third is the satisfaction of education. The club instructors of this study area had various marine sports-related licenses such as skin scuba, along with marine lifeguard trainer qualifications to prepare against safety accidents, which are also thought to have positive influences on the education satisfaction for beginners. Fourth is the inconvenient subsidiary facility. This study area has great natural environment for open waters, but the subsidiary facilities of the club for skin scuba activity was found to be very inconvenient by this study, and for the future development of skin scuba, the improvement of subsidiary facilities should be considered. Fifth is the inconvenient parking facilities. The participants in this study area agreed upon the inconvenience of the parking issue alongside the subsidiary facilities. There are always parking issues near the coasts of Busan region, and in order to resolve such issues, active assistance from the City of Busan and each local government, and if such methods are well proposed, the conflict between the marine sports participants and local residents shall be resolved, it would play a great role in the development of marine sports.

Detecting and Tracking Vehicles at Local Region by using Segmented Regions Information (분할 영역 정보를 이용한 국부 영역에서 차량 검지 및 추적)

  • Lee, Dae-Ho;Park, Young-Tae
    • Journal of KIISE:Software and Applications
    • /
    • v.34 no.10
    • /
    • pp.929-936
    • /
    • 2007
  • The novel vision-based scheme for real-time extracting traffic parameters is proposed in this paper. Detecting and tracking of vehicle is processed at local region installed by operator. Local region is divided to segmented regions by edge and frame difference, and the segmented regions are classified into vehicle, road, shadow and headlight by statistical and geometrical features. Vehicle is detected by the result of the classification. Traffic parameters such as velocity, length, occupancy and distance are estimated by tracking using template matching at local region. Because background image are not used, it is possible to utilize under various conditions such as weather, time slots and locations. It is performed well with 90.16% detection rate in various databases. If direction, angle and iris are fitted to operating conditions, we are looking forward to using as the core of traffic monitoring systems.

Free Toe Tissue Transfer using Infiltration Method of Local Anesthetic Agent (국소 침윤마취법을 이용한 족지조직 유리 피판술)

  • Seo, Dong-Lin;Park, Seung-Ha;Lee, Byung-Ihl
    • Archives of Reconstructive Microsurgery
    • /
    • v.16 no.2
    • /
    • pp.63-67
    • /
    • 2007
  • This study was designed to introduce free toe tissue transfer using infiltration method of local anesthetic agent. Four toe pulp tissues were transferred to reconstruct finger tip defect in four patients who were not suitable for general anesthesia. Two flaps taken from the lateral side of the great toe was used for reconstruction of thumb defect and two flaps from the medial side of the second toe for resurfacing of the index and fifth finger. Flap sizes were various from $2.0{\times}2.0\;cm^2$ to $1.6{\times}4.0\;cm^2$. Anesthesia was induced by infiltration of 2% lidocaine hydrochloride (with 1:100,000 epinephrine) with dilution of normal saline in same volume unit, as like as in ordinary digital block. All vessels were anastomosed within 2 cm of distance from the proximal margin of the defect. Whole operative procedures were carried out by one team. All flaps were successfully taken without complication. The average operation time was 4 hours 10 minutes. The amount of anesthetic agent used in whole operative procedures was roughly 4 mL in the toe, 8 mL in the finger, and 12 mL totally. In conclusion, free toe tissue transfer using infiltration method of local anesthetic agent would be good strategy for finger tip reconstruction in the patient not suitable for general anesthesia.

  • PDF

RETRIEVAL OF LOCAL INTERPLANETARY DUST EMISSIVITY BY ASTRO-F

  • HONG S. S.;KWON S. M.;PYO J.;UENO M.;ISHIGURO M.;USUI F.;WEINBERG J. L.
    • Journal of The Korean Astronomical Society
    • /
    • v.37 no.4
    • /
    • pp.159-169
    • /
    • 2004
  • This is a proposal to probe local part of the interplanetary dust (IPD) cloud complex and retrieve mean volume emissivity of the local IPDs at mid-infrared wavelengths. This will be done by monitoring, with Infrared Camera (IRC) aboard the ASTRO-F, the annual modulation of the zodiacal emission. In pointing mode of the ASTRO-F mission the spacecraft can make attitude maneuvering over approximately ${\pm}1^{\circ}$ range centered at solar elongation $90^{\circ}$ in the ecliptic plane. The attitude maneuvering combined with high sensitivity of the IRC will provide us with a unique opportunity observationally to take derivatives of the zodiacal emission brightness with respect to the solar elongation. From the resulting differential of the brightness over the ${\pm}1^{\circ}$ range, one can directly determine the mean volume emissivity of the local IPDs with a sufficient accuracy to de-modulate the annual emissivity variations due to the Earth's elliptical motion and the dis-alignment of the maximum IPD density plane with respect to the ecliptic. The non-zero eccentricity ($e_{\oplus}$= 0.0167) of the Earth's orbit combined with the sensitive temperature dependence of the Planck function would bring modulations of amplitude at least $3.34\%$ to the zodiacal emission brightness at mid-infrared wavelengths, with which one may determine the IPD temperature T(r) and mean number density n(r) as functions of heliocentric distance r. This will in turn fix the power-law exponent $\delta$ in the relation $T(r) = T_o(r/r_o)^{-\delta}$ for the dust temperature and v in $n(r) = n_o(r/r_o)^-v$ for the density. We discuss how one may de-couple the notorious degeneracy of cross-section, density, reference temperature $T_o$ and exponent $\delta$.

Local Environmental Effects on AGN Activities

  • Kim, Jaemin;Yi, Sukyoung K.
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.38 no.1
    • /
    • pp.43.2-43.2
    • /
    • 2013
  • The local environmental effects on the triggering of active galactic nucleus(AGN) activity has been studied with many authors, but there still be controversy. We perform statistical analysis for nearby(0.01 < z < 0.05) volume limited(Mr < -19) samples with visual inspection based on Sloan Digital Sky Survey Data Release7. We inspect ~60,000 galaxy images visually to find peculiar objects which show not only ongoing merging features and tidal features, but also post merging features like ring or shell structures. We found that these peculiar features were shown at least 2 times more frequently among AGN host galaxies than non AGN galaxies, and this trend was still visible when galaxy properties such as color or stellar mass are fixed. Furthermore, L[OIII] and L(Ha) of peculiar galaxies are found to be more increased than those of normal galaxies. In order to ensure this results, we also checked it for a smaller subsample with ~2mag deeper monochromatic images provided from SDSS Stripe82 database, and found consistent results. At last, we perform the same work for pair(r_p<80kpc/h, delta_v<200km/s) systems. Because of some pair systems which do not interact gravitationally in actuality but fulfill the criteria for identification of pair system, the trends are found to be slightly weaker. We also found that line luminosities are increased consistently as projected distance between central and companion galaxy decreased, and as companion color gets bluer. Overall, the results of this study tell us that the local environment of galaxies affect the frequency as well as the strength of AGN activity. Local environmental effects, however, may not be the dominant triggering mechanism for AGN activity since the majority of peculiar galaxies are non AGN galaxies.

  • PDF