• Title/Summary/Keyword: Spatial Orientation

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Formation and Variation of Turbidity Maximum in the Neuse River Estuary, North Carolina, U.S.A. (Neuse강 하구의 최대혼탁수 형성과 변동)

  • KIM Seok-Yun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.6
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    • pp.754-770
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    • 1994
  • Suspended sediment distribution and water column processes in the upper Neuse River estuary, North Carolina, were monitored monthly from February 1988 through February 1989, in order to identify the turbidity maximum, to determine its temporal and spatial variation under changing conditions(freshwater runoff, wind, and tide). During most of the observation periods a weak turbidity maximum, associated with the estuarine circulation processes, developed at a flow convergence zone, near the upstream limit of salt intrusion. No turbidity maximum was found when the water column was vertically homogeneous with respect to salinity and when there was no consistent upstream bottom flow. Annual migration of the turbidity maximum, accompanied by migration of salt intrusion, was over 20 km of the upper estuary. Due to the coincidence of dominant wind direction(NE-SW) with the main orientation of the Pamlico-Neuse system, wind played the dominant role in dynamics of the turbidity maximum by influencing the degree of salinity stratification and the extent and strength of estuarine circulation. Tidal effects on the sediment dynamics were negligible.

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Visual Information Selection Mechanism Based on Human Visual Attention (인간의 주의시각에 기반한 시각정보 선택 방법)

  • Cheoi, Kyung-Joo;Park, Min-Chul
    • Journal of Korea Multimedia Society
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    • v.14 no.3
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    • pp.378-391
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    • 2011
  • In this paper, we suggest a novel method of selecting visual information based on bottom-up visual attention of human. We propose a new model that improve accuracy of detecting attention region by using depth information in addition to low-level spatial features such as color, lightness, orientation, form and temporal feature such as motion. Motion is important cue when we derive temporal saliency. But noise obtained during the input and computation process deteriorates accuracy of temporal saliency Our system exploited the result of psychological studies in order to remove the noise from motion information. Although typical systems get problems in determining the saliency if several salient regions are partially occluded and/or have almost equal saliency, our system is able to separate the regions with high accuracy. Spatiotemporally separated prominent regions in the first stage are prioritized using depth value one by one in the second stage. Experiment result shows that our system can describe the salient regions with higher accuracy than the previous approaches do.

A Study on the Relationship between Urban Block Division and Unit Plans of Korean Modern Traditional Style Houses - Focused on the Ikseon-Dong 166 - (도시형한옥 주거지의 블록구획과 주거평면의 관계에 관한 연구 - 익선동 166번지 사례를 중심으로 -)

  • O, Ukn;Seo, Hyun
    • Journal of architectural history
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    • v.22 no.3
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    • pp.7-14
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    • 2013
  • Ikseon-Dong 166 is one of the traditional urban resident area developed during 1930's. The purpose of this research is to analyze the structural relationship between a conventional housing unit plans and modern block plans based on orthogonal geometry. To fully explore the selling point of the new urban development, the planner or real estate developer in private sector did not abandon or compromise the conventional house layouts, consists of single layer of rooms keeping the main room facing south. This study concludes the following factors connecting the urban and architectural plans. Oblong block plans following east-west direction did not allow the southern exposure of courtyard and main room, which was the absolute requirement for traditional house units, the longer side of block plan followed north-south direction as a result. Considering the possibility of rent, having entrance at the east or west side of individual site enables two separate household maintain their spatial privacy. In addition to the factors mentioned above, when the blocks are to be divided into individual addresses, north-south oblong block plans maintained the length to face the front road minimum while the southern exposure maximized. These factors explains why the private developers maintained their blocks elongated to north-south direction when the block plans laied out by public sectors which did not care that much of southern exposure show random orientation in the view point of solar exposure.

Development of a Lane Detect Algorithm from Road-Facing Cameras on a Vehicle (차량에 부착된 측하방 CCD카메라를 이용한 차선추출 알고리즘 개발)

  • Rhee, Soo-Ahm;Lee, Tae-Yoon;Kim, Tae-Jung;Sung, Jung-Gon
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.3 s.33
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    • pp.87-94
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    • 2005
  • 3D positional information of lane can be automatically calculated tv combining GPS data, IMU data if coordinates of lane centers are given. The Road Safety Survey and Analysis Vehicle(RoSSAV) is currently under development to analyze three dimensional safety and stability of roads. RoSSAV has GPS and IMU sensors to get positional information of the vehicle and two road-facing CCD cameras for extraction of lane coordinates. In this paper, we develop technology that automatically detects centers of lanes from the road-facing cameras of RoSSAV. The proposed algorithm defines line-support regions by grouping pixels with similar edge orientation and magnitude together and extracts a line from each line support region by planar fitting. Then if extracted lines and the region in-between satisfy the criteria of brightness and width, we decide this region as lane. The proposed algorithm was more precise and stable than the previously proposed algorithm based on brightness threshold method. Experiments with real road scenes confirmed that lane was effectively extracted by the proposed algorithm.

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The Digital Drawing Production Using Digital Camera (디지털 카메라를 이용한 수치도면작성)

  • Choi, Seung-Pil;Park, Jong-Sun;Choi, Chul-Soon
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.3 s.30
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    • pp.91-97
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    • 2004
  • As for the former analogue method of photogrammetry, We have obtained final digital drawing by creating the stereo model from overlapped images through orientation process using plotting instrument and processing restitution procedure. However, digital photogrammetry batch processes such using small computer system thus We make an attempt automatization of the procedures. And without the production of stereo model, We could obtain 3D digital data through analysis method. Therefore, an objective of this study was to implement a surveying system that could 3D surveying positions using the digital image to reduce limitations of control point surveying and photographing conditions more efficiently to produce digital drawing. By the result, photogrammetry can practice and make out digital drawing to a computer by digital camera of a comparative low-cost. Small scale area can become practical use to drawing production etc. for facilities management because area can make out digital drawing economically than general surveying.

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Recovering Corrupted Motion Vectors using Discontinuity Features of an Image (영상의 불연속 특성을 이용한 손상된 움직임 벡터 복원 기법)

  • 손남례;이귀상
    • Journal of KIISE:Information Networking
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    • v.31 no.3
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    • pp.298-304
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    • 2004
  • In transmitting a compressed video bit-stream over Internet, a packet loss causes an error propagation in both spatial and temporal domain, which in turn leads to a severe degradation in image quality. In this paper, a new error concealment algorithm is proposed to repair damaged portions of the video frames in the receiver. Conventional BMA(Boundary Matching Algorithm) assumes that the pixels on the boundary of the missing block and its neighboring blocks are very similar, but has no consideration of edges t)r discontinuity across the boundary. In our approach, the edges are detected across the boundary of the lost or erroneous block. Once the edges are detected and the orientation of each edge is found, only the pixel difference along the expected edges across the boundary is measured instead of calculating differences between all adjacent pixels on the boundary. Therefore, the proposed approach needs very few computations and the experiment shows an improvement of the performance over the conventional BMA in terms of both subjective and objective quality of video sequences.

Direction Relation Representation and Reasoning for Indoor Service Robots (실내 서비스 로봇을 위한 방향 관계 표현과 추론)

  • Lee, Seokjun;Kim, Jonghoon;Kim, Incheol
    • Journal of KIISE
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    • v.45 no.3
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    • pp.211-223
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    • 2018
  • In this paper, we propose a robot-centered direction relation representation and the relevant reasoning methods for indoor service robots. Many conventional works on qualitative spatial reasoning, when deciding the relative direction relation of the target object, are based on the use of position information only. These reasoning methods may infer an incorrect direction relation of the target object relative to the robot, since they do not take into consideration the heading direction of the robot itself as the base object. In this paper, we present a robot-centered direction relation representation and the reasoning methods. When deciding the relative directional relationship of target objects based on the robot in an indoor environment, the proposed methods make use of the orientation information as well as the position information of the robot. The robot-centered reasoning methods are implemented by extending the existing cone-based, matrix-based, and hybrid methods which utilized only the position information of two objects. In various experiments with both the physical Turtlebot and the simulated one, the proposed representation and reasoning methods displayed their high performance and applicability.

Geometric calibration of digital photogrammetric camera in Sejong Test-bed (세종 테스트베드에서 항측용 디지털카메라의 기하학적 검정)

  • Seo, Sang-Il;Won, Jae-Ho;Lee, Jae-One;Park, Byoung-Uk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.2
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    • pp.181-188
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    • 2012
  • The most recent, Digital photogrammetric camera, Airborne LiDAR and GPS/INS same sensors are used to acquire spatial information of various kinds in the field of aerial survey. In addition, Direct Georeferencing technology has been widely utilized with digital photogrammetric camera and GPS/INS. However, the sensor Calibration to be performed according to the combination of various sensors is followed by problems. Most of all, boresight calibration of integrated sensors is a critical element in the mapping process when using direct georeferencing or using the GPS/INS aerotriangulation. The establishment of a national test-bed in Sejong-si for aerial sensor calibration is absolutely necessary to solve this problem. And accurate calibration with used to integration of GPS/INS by aerotriangulation of aerial imagery was necessary for determination of system parameters, evaluation of systematic errors. Also, an investigation of efficient method for Direct georeferencing to determine the exterior orientation parameters and assessment of geometric accuracy of integrated sensors are performed.

Effects of Electroacupuncture on the excitability in Medial Vestibular Nuclei of Rats (흰쥐의 내측 전정신경핵 흥분성에 대한 전침자극의 효과)

  • Kim, Jae-Hyo;Lee, Sung-Ho;Sohn, In-Chul;Kim, Young-Sun;Kim, Min-Sun
    • Korean Journal of Acupuncture
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    • v.26 no.3
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    • pp.27-42
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    • 2009
  • Objectives : The vestibular system detects head movement and serve to regulate and maintain the equilibrium and orientation of the body. It is known that the vestibular imbalance leads to vestibular symptoms such as nausea, vomiting, vertigo and postural disturbance. The objectives of the present study were to examine a modification of the dynamic activities of medial vestibular nucleus (MVN) neurons following electroacupuncture (EA) of GB43 (Hyepgye). Methods : In Sprague-Dawley rats weighing $250{\sim}300g$, dynamic responses induced by sinusoidal whole body rotation about vertical axis at 0.2 Hz were observed in MVN of rats during EA of GB43 (Hyepgye) with 0.2 ms, 40 Hz and $600{\pm}200{\mu}A$. Also, expression of cFos protein was observed 2 hours after EA for 30 mins. Results : In dynamic response of vestibular neuron, the excitatory or inhibitory responses of gain were predominant in the ipsilateral MVN neurons during EA but not predominant in the contralateral MVN. Most neurons showing decreased gain were classified to inhibitory responses of spontaneous firing discharge during EA and ones showing increased gain were classified to excitatory response of spontaneous firing discharge during EA. Also, EA of the left GB43 (Hyepgye) for 30 mins produced the expression of cFos protein in MVN, inferior olive (IO) and solitary tract nuclei (SOL). Spatial expressions of cFos protein were predominant in the contralateral MVN, ipsilateral IO and bilateral SOL. Conclusion : These results suggest that the excitability of MVN neurons was influenced by EA of GB43 (Hyepgye) and EA may be related to the convergence on MVN.

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"Dust, Ice, and Gas In Time" (DIGIT) Herschel Observations of GSS30-IRS1 in Ophiuchus

  • Je, Hyerin;Lee, Jeong-Eun;Green, Joel D.;Evans, Neal J. II
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.63.2-63.2
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    • 2014
  • As a part of the "Dust, Ice, and Gas In Time" (DIGIT) key program on Herschel, we observed GSS30-IRS1, a Class I protostar located in Ophiuchus (d =125 pc), with Herschel/Photodetector Array Camera and Spectrometer (PACS). More than 70 lines were detected within a wavelength range from 50 ${\mu}m$ to 200 ${\mu}m$: CO lines from J = 14-13 to 41-40, several $H_2O$ lines of Eup = 100 K to 1500 K, 16 transitions of OH rotational lines, and two atomic [O I] lines at 63 and 145 ${\mu}m$. The [C II] line, known as a tracer of externally heated gas by the interstellar radiation field, is also detected at 158 ${\mu}m$. All lines, except [O I] and [C II], are detected only at the central spaxel of $9^{\prime\prime}.4{\times}9^{\prime\prime}.4$. The [O I] emission is extended along a NE-SW orientation, which is consistent with the known outflow direction, while the [C II] line is detected over all spaxels. One possible explanation of the detection of the [C II] line and no correlation of its spatial distribution with any other molecular emission is the existence of the enhanced ISRF nearby GSS30-IRS1. One interesting feature of GSS30-IRS1 is that the continuum emission is extended beyond the point-spread function (PSF), unlike the molecular line emission, indicative of significant external heating. The best-fit continuum model of GSS30-IRS1 with the physical structure including flared disk, envelope, and outflow shows that the internal luminosity is 11 $L_{\odot}$, and the region is also externally heated by a radiation field enhanced by a factor of 25 compared to the local standard interstellar field.

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