• Title/Summary/Keyword: Smart Ground

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Three-Dimensional Positional Accuracy Analysis of UAV Imagery Using Ground Control Points Acquired from Multisource Geospatial Data (다종 공간정보로부터 취득한 지상기준점을 활용한 UAV 영상의 3차원 위치 정확도 비교 분석)

  • Park, Soyeon;Choi, Yoonjo;Bae, Junsu;Hong, Seunghwan;Sohn, Hong-Gyoo
    • Korean Journal of Remote Sensing
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    • v.36 no.5_3
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    • pp.1013-1025
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    • 2020
  • Unmanned Aerial Vehicle (UAV) platform is being widely used in disaster monitoring and smart city, having the advantage of being able to quickly acquire images in small areas at a low cost. Ground Control Points (GCPs) for positioning UAV images are essential to acquire cm-level accuracy when producing UAV-based orthoimages and Digital Surface Model (DSM). However, the on-site acquisition of GCPs takes considerable manpower and time. This research aims to provide an efficient and accurate way to replace the on-site GNSS surveying with three different sources of geospatial data. The three geospatial data used in this study is as follows; 1) 25 cm aerial orthoimages, and Digital Elevation Model (DEM) based on 1:1000 digital topographic map, 2) point cloud data acquired by Mobile Mapping System (MMS), and 3) hybrid point cloud data created by merging MMS data with UAV data. For each dataset a three-dimensional positional accuracy analysis of UAV-based orthoimage and DSM was performed by comparing differences in three-dimensional coordinates of independent check point obtained with those of the RTK-GNSS survey. The result shows the third case, in which MMS data and UAV data combined, to be the most accurate, showing an RMSE accuracy of 8.9 cm in horizontal and 24.5 cm in vertical, respectively. In addition, it has been shown that the distribution of geospatial GCPs has more sensitive on the vertical accuracy than on horizontal accuracy.

Evaluation on the Reliability of Frost Susceptibility Criteria (동상민감성 판정 기준 신뢰성에 관한 연구)

  • Jin, Hyunwoo;Ryu, Byunghyun;Lee, Jangguen
    • Journal of the Korean GEO-environmental Society
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    • v.18 no.12
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    • pp.37-45
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    • 2017
  • Structural instability and damage are caused by frost heave during the winter when atmospheric temperature maintains below $0^{\circ}C$. Frost heave is the most representative engineering characteristics of frozen ground and there are various frost susceptibility criteria. Frost susceptibility criteria can be roughly divided into three categories. First, frost susceptibility is determined from particle size distribution, which is practically useful and many countries are adopting. In this paper, several particle size distributions (PSDs) are applied to the frost susceptibility criteria but PSD seems to be not enough to determine whether soils are frost susceptible. Second, it is judged from laboratory frost heave testing results. Laboratory frost heave tests were performed with newly developed thermal controlled triaxial cell and the reliability of frost susceptibility criteria is evaluated. New testing apparatus and method are suitable to meet the existing frost susceptibility criteria. Third, it is compositive frost susceptibility criteria envelope including the particle size distribution, soil classification, and frost heave test. The compositive frost susceptibility criteria envelope should be supplemented based on additional data on various soil types.

Design and Fabrication of a Quadruple Band Antenna for WLAN/WiMAX Systems (900 MHz 대역을 포함한 WLAN/WiMAX 시스템에 적용 가능한 4중대역 안테나 설계 및 제작)

  • Park, Sang-wook;Choi, Tea-Il;Choi, Young-kyu;Yoon, Joong-Han
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.10
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    • pp.1240-1247
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    • 2019
  • In this paper, we designed a four-band antenna that can be applied to WLAN and WiMAX systems by designing a microstrip feeding structure, four branch lines and a slit on the ground plane. The proposed antenna is designed with a size of 16.0 mm (W1) × 48.0 mm (L8) on a dielectric substrate of 18.0 mm (W) × 50.0 mm (L) × 1.0 mm(h). and a slit of 2.9 mm (W7) × 4.0 mm (L7) is inserted into the ground plane of 18.0 mm (W) × 18.7 mm (L6). Based on -10 dB production and measurement results, it obtained 60.8 MHz (8,730~9,338 MHz), 310 MHz (2.33~2.64 GHz) in the 2.4 GHz band, 420MHz (3.39~3.81 GHz) in the 3.4 GHz band, and 2,070 MHz (4.62~6.69 GHz) in the 5.0 GHz. In addition, the gain and radiation pattern characteristics of the quadrant band are measured from the measurement results anechoic chamber.

A Study on the Optimal Setting of Large Uncharged Hole Boring Machine for Reducing Blast-induced Vibration Using Deep Learning (터널 발파 진동 저감을 위한 대구경 무장약공 천공 장비의 최적 세팅조건 산정을 위한 딥러닝 적용에 관한 연구)

  • Kim, Min-Seong;Lee, Je-Kyum;Choi, Yo-Hyun;Kim, Seon-Hong;Jeong, Keon-Woong;Kim, Ki-Lim;Lee, Sean Seungwon
    • Explosives and Blasting
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    • v.38 no.4
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    • pp.16-25
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    • 2020
  • Multi-setting smart-investigation of the ground and large uncharged hole boring (MSP) method to reduce the blast-induced vibration in a tunnel excavation is carried out over 50m of long-distance boring in a horizontal direction and thus has been accompanied by deviations in boring alignment because of the heavy and one-directional rotation of the rod. Therefore, the deviation has been adjusted through the boring machine's variable setting rely on the previous construction records and expert's experience. However, the geological characteristics, machine conditions, and inexperienced workers have caused significant deviation from the target alignment. The excessive deviation from the boring target may cause a delay in the construction schedule and economic losses. A deep learning-based prediction model has been developed to discover an ideal initial setting of the MSP machine. Dropout, early stopping, pre-training techniques have been employed to prevent overfitting in the training phase and, significantly improved the prediction results. These results showed the high possibility of developing the model to suggest the boring machine's optimum initial setting. We expect that optimized setting guidelines can be further developed through the continuous addition of the data and the additional consideration of the other factors.

Proposal for Evacuee Guidance of Cloud-based Elevator System in Emergency Situation (클라우드 기반 비상탈출 시 피난유도 승강기시스템 제안)

  • Choi, Jun-Ho;Shin, Seung-Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.25-28
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    • 2015
  • Lifts are used as an essential means of transportation within the building in an emergency situation, when used as a means of escape, so expect a lot of research has been conducted high effect. Number of stories in the Seoul-rise building guidelines underground 7th floor, 53 ground floor, floor area $6,800m^2$, floor area $127,050m^2$, use is cultural and convention facilities and sales facilities, business facilities and accommodation (hotel), the construction of public housing (apartments) hagieneun not efficient to install elevators for evacuation mothada was determined separately in designing the lift is designed according to the standards of passenger lifts installed under a judgment as to use for evacuation. However, this does not include detailed design guidelines so far.[1] We propose the Evacuee Guidance of Elevator System that can be used as entering air equipment, sprinkler and smart phone evacuation system.

A Study on the Eye-line Detection from Facial Image taken by Smart Phone (스마트 폰에서 취득한 얼굴영상에서 아이라인 검출에 관한 연구)

  • Koo, Ha-Sung;Song, Ho-Geun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.10
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    • pp.2231-2238
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    • 2011
  • In this paper, the extract method of eye and eye-line from picture of a person is proposed. Most of existing papers are to extract the position of eyeball but in this paper, by extracting not only the position of eyeball but also eye-line, it can be applied to the face application program variously. The experimental data of the input picture is a full face photograph taken by smart phone, basically the picture is limited to the face of one person and back ground can be taken from every where and no restriction of race. The proposed method is to extract face candidated area by using Harr Classifier and set up the candidate area of eye position from face candidate area. To extract high value from eye candidate area using dilate operation, and proposed the method to classify eye and eyelash by local thresholding of the picture. After that, using thresholding image from eyemapC that Hsu's suggested, and separated the area with eye and without eye. Finally extract the contour of eye and detect eye-line using optimum ellipse estimation.

A study about structural analysis of double structured non-pneumatic wheel (이중구조를 가진 비공기압바퀴의 구조해석에 관한 연구)

  • Song, Gi-Hwan;Lee, Sang-Hun;Son, Chang-Woo;Seo, Hyoung-Jin;Seo, Tae-Il;Yoo, Wha-Wul;Park, Sung-Hak;Park, Kyung-Hoon
    • Design & Manufacturing
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    • v.9 no.3
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    • pp.19-23
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    • 2015
  • Non-pneumatic wheels have been widely used instead of general tube type wheels beause of many reasons, for example, wheel size, price restriction, heavy-duty problem and so on. Almost small size wheels or casters were non-pneumatic type but structural stability was not certified. This paper presents a double structured non-pneumatic wheel, called "smart caster", which consisted with inner and outer wheels connected by chips, and finite element analysis processes were conducted in order to determine important dwsign factors before actual design for mass production. For structural analysis ABAQUS was used under various boundary conditions with incrementally varied loads until 2,000N. Then structural staility was evaluated according to varied loads below ultimate stress. Generally stresses were concentrated at the lower parts of the wheel, and especially contact parts between wheel and ground. In addition, maximum stress appeared at contact parts between the wheel lower part and chips.

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Developing a smart structure using integrated DDA/ISMP and semi-active variable stiffness device

  • Karami, Kaveh;Nagarajaiah, Satish;Amini, Fereidoun
    • Smart Structures and Systems
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    • v.18 no.5
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    • pp.955-982
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    • 2016
  • Recent studies integrating vibration control and structural health monitoring (SHM) use control devices and control algorithms to enable system identification and damage detection. In this study real-time SHM is used to enhance structural vibration control and reduce damage. A newly proposed control algorithm, including integrated real-time SHM and semi-active control strategy, is presented to mitigate both damage and seismic response of the main structure under strong seismic ground motion. The semi-active independently variable stiffness (SAIVS) device is used as semi-active control device in this investigation. The proper stiffness of SAIVS device is obtained using a new developed semi-active control algorithm based on real-time damage tracking of structure by damage detection algorithm based on identified system Markov parameters (DDA/ISMP) method. A three bay five story steel braced frame structure, which is equipped with one SAIVS device at each story, is employed to illustrate the efficiency of the proposed algorithm. The obtained results show that the proposed control algorithm could significantly decrease damage in most parts of the structure. Also, the dynamic response of the structure is effectively reduced by using the proposed control algorithm during four strong earthquakes. In comparison to passive on and off cases, the results demonstrate that the performance of the proposed control algorithm in decreasing both damage and dynamic responses of structure is significantly enhanced than the passive cases. Furthermore, from the energy consumption point of view the maximum and the cumulative control force in the proposed control algorithm is less than the passive-on case, considerably.

One Step Measurements of hippocampal Pure Volumes from MRI Data Using an Ensemble Model of 3-D Convolutional Neural Network

  • Basher, Abol;Ahmed, Samsuddin;Jung, Ho Yub
    • Smart Media Journal
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    • v.9 no.2
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    • pp.22-32
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    • 2020
  • The hippocampal volume atrophy is known to be linked with neuro-degenerative disorders and it is also one of the most important early biomarkers for Alzheimer's disease detection. The measurements of hippocampal pure volumes from Magnetic Resonance Imaging (MRI) is a crucial task and state-of-the-art methods require a large amount of time. In addition, the structural brain development is investigated using MRI data, where brain morphometry (e.g. cortical thickness, volume, surface area etc.) study is one of the significant parts of the analysis. In this study, we have proposed a patch-based ensemble model of 3-D convolutional neural network (CNN) to measure the hippocampal pure volume from MRI data. The 3-D patches were extracted from the volumetric MRI scans to train the proposed 3-D CNN models. The trained models are used to construct the ensemble 3-D CNN model and the aggregated model predicts the pure volume in one-step in the test phase. Our approach takes only 5 seconds to estimate the volumes from an MRI scan. The average errors for the proposed ensemble 3-D CNN model are 11.7±8.8 (error%±STD) and 12.5±12.8 (error%±STD) for the left and right hippocampi of 65 test MRI scans, respectively. The quantitative study on the predicted volumes over the ground truth volumes shows that the proposed approach can be used as a proxy.

System identification of soil behavior from vertical seismic arrays

  • Glaser, Steven D.;Ni, Sheng-Huoo;Ko, Chi-Chih
    • Smart Structures and Systems
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    • v.4 no.6
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    • pp.727-740
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    • 2008
  • A down hole vertical seismic array is a sequence of instruments installed at various depths in the earth to record the ground motion at multiple points during an earthquake. Numerous studies demonstrate the unique utility of vertical seismic arrays for studying in situ site response and soil behavior. Examples are given of analyses made at two sites to show the value of data from vertical seismic arrays. The sites examined are the Lotung, Taiwan SMART1 array and a new site installed at Jingliao, Taiwan. Details of the installation of the Jingliao array are given. ARX models are theoretically the correct process models for vertical wave propagation in the layered earth, and are used to linearly map deeper sensor input signals to shallower sensor output signals. An example of Event 16 at the Lotung array is given. This same data, when examined in detail with a Bayesian inference model, can also be explained by nonlinear filters yielding commonly accepted soil degradation curves. Results from applying an ARMAX model to data from the Jingliao vertical seismic array are presented. Estimates of inter-transducer soil increment resonant frequency, shear modulus, and damping ratio are presented. The shear modulus varied from 50 to 150 MPa, and damping ratio between 8% and 15%. A new hardware monitoring system - TerraScope - is an affordable 4-D down-hole seismic monitoring system based on independent, microprocessor-controlled sensor Pods. The Pods are nominally 50 mm in diameter, and about 120 mm long. An internal 16-bit micro-controller oversees all aspects of instrumentation, eight programmable gain amplifiers, and local signal storage.