• 제목/요약/키워드: Environment Mapping

검색결과 819건 처리시간 0.028초

온톨로지 매핑 기반 엔지니어링 정보 검색 (Engineering Information Search based on Ontology Mapping)

  • 정민;서효원
    • 한국정밀공학회지
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    • 제23권5호
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    • pp.30-36
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    • 2006
  • The participants in collaborative environment want to get the right information or documents which are intended to find. In general search systems, documents which contain only the keywords are retrieved. For searching different word-expressions for the same meaning, we perform mapping before searching. Our mapping-based search approach has two parts, ontology-based mapping logic and ontology libraries. The ontology-based mapping consists of three steps such as character matching (CM), definition comparing (DC) and similarity checking (SC). First, the character matching is the mapping of two terminologies that have identical character strings. Second, the definition comparing is the method that compares two terminologies' ontological definitions. Third, the similarity checking pairs two terminologies which were not mapped by two prior steps through evaluating the similarity of the ontological definitions. For the ontology libraries, document ontology library (DOL), keyword ontology library (KOL), and mapping result library (MRL) are defined. With these three libraries and three mapping steps, an ontology-based search engine (OntSE) is built, and a use case scenario is discussed to show the applicability.

비정형의 건설환경 매핑을 위한 레이저 반사광 강도와 주변광을 활용한 향상된 라이다-관성 슬램 (Intensity and Ambient Enhanced Lidar-Inertial SLAM for Unstructured Construction Environment)

  • 정민우;정상우;장혜수;김아영
    • 로봇학회논문지
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    • 제16권3호
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    • pp.179-188
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    • 2021
  • Construction monitoring is one of the key modules in smart construction. Unlike structured urban environment, construction site mapping is challenging due to the characteristics of an unstructured environment. For example, irregular feature points and matching prohibit creating a map for management. To tackle this issue, we propose a system for data acquisition in unstructured environment and a framework for Intensity and Ambient Enhanced Lidar Inertial Odometry via Smoothing and Mapping, IA-LIO-SAM, that achieves highly accurate robot trajectories and mapping. IA-LIO-SAM utilizes a factor graph same as Tightly-coupled Lidar Inertial Odometry via Smoothing and Mapping (LIO-SAM). Enhancing the existing LIO-SAM, IA-LIO-SAM leverages point's intensity and ambient value to remove unnecessary feature points. These additional values also perform as a new factor of the K-Nearest Neighbor algorithm (KNN), allowing accurate comparisons between stored points and scanned points. The performance was verified in three different environments and compared with LIO-SAM.

A Study on Optimized Mapping Environment for Real-time Spatial Mapping of HoloLens

  • Hwang, Leehwan;Lee, Jaehyun;Hafeez, Jahanzeb;Kang, Jinwook;Lee, Seunghyun;Kwon, Soonchul
    • International Journal of Internet, Broadcasting and Communication
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    • 제9권3호
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    • pp.1-8
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    • 2017
  • Recently, the development of the head mounted display (HMD) device has attracted a great deal of attention to the actual contents. Especially, Augmented Reality (AR), which is a mixture of actual information and virtual world information, is focused on. AR HMD is able to interact by arranging virtual objects in real space through spatial recognition using depth camera. In order to naturally mix virtual space with real space, it is necessary to develop a technology for realizing spatial mapping information with high accuracy. The purpose of this paper is to evaluate the optimal configuration of augmented reality application program by realizing accurate spatial mapping information when mapping a real space and an object placement environment using HoloLens. To do this, we changed the spatial mapping information in real space to three levels, which are the number of meshes used in cubic meters to scan step by step. After that, it was compared with the 3D model obtained by changing the actual space and mesh number. Experimental result shows that the higher the number of meshes used in cubic meters, the higher the accuracy between real space and spatial mapping. This paper is expected to be applied to augmented reality application programs that require scanning of highly mapped spatial mapping information.

PollMap: a software for crop pollination mapping in agricultural landscapes

  • Rahimi, Ehsan;Barghjelveh, Shahindokht;Dong, Pinliang;Pirlar, Maghsoud Arshadi;Jahanbakhshian, Mohammad Mehdi
    • Journal of Ecology and Environment
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    • 제45권4호
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    • pp.255-263
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    • 2021
  • Background: Ecosystem service mapping is an important tool for decision-making in landscape planning and natural resource management. Today, pollination service mapping is based on the Lonsdorf model (InVEST software) that determines the availability of nesting and floral resources for each land cover and estimates pollination according to the foraging range of the desired species. However, it is argued that the Lonsdorf model has significant limitations in estimating pollination in a landscape that can affect the results of this model. Results: This paper presents a free software, named PollMap, that does not have the limitations of the Lonsdorf model. PollMap estimates the pollination service according to a modified version of the Lonsdorf model and assumes that only cells within the flight range of bees are important in the pollination mapping. This software is produced for estimating and mapping crop pollination in agricultural landscapes. The main assumption of this software is that in the agricultural landscapes, which are dominated by forest and agriculture ecosystems, forest patches serve only as a nesting habitat for wild bees and the surrounding fields provide floral resources. Conclusion: The present study provided new software for mapping crop pollination in agricultural landscapes that does not have the limitations of the Lonsdorf model. We showed that the use of the Lonsdorf model for pollination mapping requires attention to the limitations of this model, and by removing these limitations, we will need new software to obtain a reliable mapping of pollination in agricultural landscapes.

Robust range-only beacon mapping in multipath environments

  • Park, Byungjae;Lee, Sejin
    • ETRI Journal
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    • 제42권1호
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    • pp.108-117
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    • 2020
  • This study proposes a robust range-only beacon mapping method for registering the locations of range-only beacons automatically. The proposed method deals with the multipath propagation of signals from range-only beacons using the range-only measurement association (RoMA) and an unscented Kalman filter (UKF). The RoMA initially predicts the candidate positions of a range-only beacon. The location of the range-only beacon is then updated using the UKF. With the proposed method, the locations of range-only beacons are accurately estimated in a multipath environment. The proposed method also provides the location uncertainty of each range-only beacon. Simulation results using the model for multipath propagation and experimental results in a real indoor environment verify the performance of the proposed method.

A New Fast P2P Video Transmission Method Applied in Asymmetrical Speed Channel Environment

  • Wang, Zhang;Zhang, Jixian;Li, Haitao;Liu, Jian
    • Journal of Communications and Networks
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    • 제12권3호
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    • pp.209-215
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    • 2010
  • In an asymmetrical speed channel environment like asymmetric digital subscriber line, the up-link bandwidth is normally smaller than the down-link bandwidth, which will lead to extremely low utilization of down-link bandwidth when current P2P video transmission is applied. To overcome this, a new fast P2P video transmission method applied in an asymmetrical speed channel environment is proposed in this paper. On the basis of the many-to-one concept, the proposed method uses a new multipeer aggregation technique to enhance the utilization of down-link bandwidth. In addition, an adaptive peer assignment algorithm is also introduced in order to minimize the overall transmission time. Experimental results show that by using our proposed method, the utilization of down-link bandwidth is significantly improved, and the overall transmission time is greatly reduced.

온톨로지 기반의 용어 정의 비교 및 유사도를 고려한 의미 매핑 (Semantic Mapping of Terms Based on Their Ontological Definitions and Similarities)

  • 정원철;이재현;서효원
    • 한국CDE학회논문집
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    • 제11권3호
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    • pp.211-222
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    • 2006
  • In collaborative environment, it is necessary that the participants in collaboration should share the same understanding about the semantics of terms. For example, they should know that 'COMPONENT' and 'ITEM' are different word-expressions for the same meaning. In order to handle such problems in information sharing, an information system needs to automatically recognize that the terms have the same semantics. So we develop an algorithm mapping two terms based on their ontological definitions and their similarities. The proposed algorithm consists of four steps: the character matching, the inferencing, the definition comparing and the similarity checking. In the similarity checking step, we consider relation similarity and hierarchical similarity. The algorithm is very primitive, but it shows the possibility of semi-automatic mapping using ontology. In addition, we design a mapping procedure for a mapping system, called SOM (semantic ontology mapper).

스펙트럼사상학습을 이용한 잡음환경에서의 한국어숫자음인식 (Korean Digit Recognition Under Noise Environment Using Spectral Mapping Training)

  • 이기영
    • 한국음향학회지
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    • 제13권3호
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    • pp.25-32
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    • 1994
  • 본 연구에서는 정적지도적응알고리즘을 기초로 한 스펙트럼사상학습을 이용하여 잡음환경에서의 한국어숫자음인식방법을 제시하였다. 제시한 인식방법에서 잡음이 섞인 음성스펙트럼 공간을 잡음이 없는 음성스펙트럼 공간으로 사상한 결과, 잡음이 섞인 음성스펙트럼의 왜곡이 개선되어 잡음처리를 행하지 않은 기존의 VQ(vector quantizaton)와 DTW(dynamic time warping)를 이용한 방법보다 높은 인식율을 얻을 수 있었으며 , 0 dB의 SNR 레벨에서도 기존방법의 인식율을 10배 정도 향상시키므로써, 스펙트럼사상학습이 잡음환경의 음성에 대한 인식성능을 향상시킬 수 있는 방법임을 확인하였다.

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Evaluation of Cofactor Markers for Controlling Genetic Background Noise in QTL Mapping

  • Lee, Chaeyoung;Wu, Xiaolin
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권4호
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    • pp.473-480
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    • 2003
  • In order to control the genetic background noise in QTL mapping, cofactor markers were incorporated in single marker analysis (SMACO) and interval mapping (CIM). A simulation was performed to see how effective the cofactors were by the number of QTL, the number and the type of markers, and the marker spacing. The results of QTL mapping for the simulated data showed that the use of cofactors was slightly effective when detecting a single QTL. On the other hand, a considerable improvement was observed when dealing with more than one QTL. Genetic background noise was efficiently absorbed with linked markers rather than unlinked markers. Furthermore, the efficiency was different in QTL mapping depending on the type of linked markers. Well-chosen markers in both SMACO and CIM made the range of linkage position for a significant QTL narrow and the estimates of QTL effects accurate. Generally, 3 to 5 cofactors offered accurate results. Over-fitting was a problem with many regressor variables when the heritability was small. Various marker spacing from 4 to 20 cM did not change greatly the detection of multiple QTLs, but they were less efficient when the marker spacing exceeded 30 cM. Likelihood ratio increased with a large heritability, and the threshold heritability for QTL detection was between 0.30 and 0.05.

클라이언트-서버 환경의 매핑 시스템 개발을 위한 복제 일관성 모델에 관한 연구 (A Study on the Replication Consistency Model for the Mapping System on the Client-Sewer Environment)

  • 이병욱;박홍기
    • 대한공간정보학회지
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    • 제5권2호
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    • pp.193-205
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    • 1997
  • 대용량의 매핑 자료를 다수의 사용자들이 효율적으로 공유하는데는 클라이언트-서버 환경에서 복제 일관성을 위한 분산 모델 개발이 요구된다. 기존의 분산 모델은 각 사이트들의 사본간의 일관성을 강조했으나 GUI를 이용한 화면과 사본간의 일관성이 고려되지 못하여 매핑 시스템과 같은 장기 트랜잭션에는 적합하지 않다. 매핑자료의 특성상 분산 환경에서 트랜잭션들의 일관성을 유지하는데는 시간 지연이 많으므로 병행효율이 중요하다. 본 연구에서는 디스플레이 록을 이용하여 GUI 화면과 사본들 사이의 일관성을 지원한다. 매핑자료의 특성을 이용하여 낙관적 병행제어 기법과 일관성 모델을 개선하여, 처리효율을 향상하는 일관성 모델을 제시한다.

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