• 수산해양기술연구
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• 제34권2호
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• pp.144-158
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• 1998

In order to study basic information on the developed electro-magnetic compass, experiments were carried out on board M. S. KAYA at the pier of Dong Kuk Steel Mill in Pusan and the Korean southern sea using a three-axis magnetic sensor from Jan. 21, 1995 to Feb. 14, 1996. The obtained results were as follows : 1. The amount of old metal on the pier was about 27,290tons~57,440tons with an average of 40,560tons, the artificial local disturbance at the pier was min. 27.1$\mu$T, max. 66.5$\mu$T, ave. 433$\mu$T for the horizontal component and min. -27.0$\mu$T, max. 45.1$\mu$T, ave. 3.7$\mu$T for the vertical component. Its direction of horizontal component was 305$^{\circ}$ with the ship's head up bearing at 225$^{\circ}$. 2. The ship's magnetic distribution on the starboard side on berthing at the pier was 17.4$\mu$T for the horizontal component and -6.2$\mu$T for the vertical component. On the ship's port side, it was 19.8$\mu$T for the horizontal component and 4.1$\mu$T for the vertical component. On the ship's starboard side at sea, the ship's magnetic distribution was 19.2$\mu$T for the horizontal component and 3.2$\mu$T for the vertical component. On the ship's port side, the readings were 22.0$\mu$T for the horizontal component and -1.8$\mu$T for the vertical component. The directions of these readings were nearly starboard side. 3. On the pier, the secular change of the artificial local disturbance decreased 8.3$\mu$T from 61.0$\mu$T to 52.7$\mu$T for the horizontal component and decreased 7.1$\mu$T from 8.9$\mu$T M 1.8$\mu$T for the vertical component. On the starboard side from its berth, the ship, s magnetic distribution increased 2.6$\mu$T from 14.8$\mu$T to 17.4$\mu$T for the horizontal component and increased -0.1$\mu$T from -6.1$\mu$T to -6.2$\mu$T for the vertical component. On the ship's port side from its berth, it increased 7.1$\mu$T from 12.7$\mu$T to 19.8$\mu$T for the horizontal component and increased 10.2$\mu$T from -6.1$\mu$T to 4.1$\mu$T for the vertical component. 4. While at sea, on the ship's starboard side, the Secular change of the ship's magnetic distribution increased 3.9$\mu$T from 15.3$\mu$T to 19.2$\mu$T for the horizontal component and increased 2.0$\mu$T from -5.2$\mu$T to -3.2$\mu$T for the vertical component. On the port side, the changes increased 11.4$\mu$T from 10.6$\mu$T to 22.0$\mu$T for the horizontal component and increased 4.9$\mu$T from -6.7$\mu$T to -1.8$\mu$T for the vertical component. Upon berthing at the pier, the deviation of the secular change increased westerly 1 degree W~ 2.5$^{\circ}$ W from 3.5$^{\circ}$ W~ 5$^{\circ}$ W M 6W with the ship's head up bearing at 225$^{\circ}$. While at sea, these increased westerly 2$^{\circ}$ ~ 3$^{\circ}$ from the Northeast to the South and increased easterly 1$^{\circ}$ ~ 8$^{\circ}$ from the Southwest to the North. 5. While at port, within 1 mile between the ship and berth of the pier, as we approached the pier, the westerly deviation increased and when we departed the pier easterly deviation increased. When approaching the pier, the deviation was smaller than the deviation when the ship was departing from the pier. When approaching the bearing at 225$^{\circ}$ with the ship's head up bearing, the varies of deviation was smaller than the varies when the ship's head up bearing was departing from it.

• 한국지능시스템학회논문지
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• 제17권2호
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• pp.208-213
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• 2007

최근 가정용 로봇 연구가 활발히 진행됨에 따라, 가정과 같은 다이내믹한 환경에서 로봇이 목소리를 포함한 음원에 반응하고 그 위치를 정확히 찾아가는 것이 매우 중요해지고 있다. 인간이 목표물에 도달하기 위해 경로를 선택할 때, 그 목표물이 소리인 경우는 현재 위치에서 음원의 방향을 추적한다. 또한 그 목표물의 위치가 지도로 주워질 경우에는 현재 위치와 목표물의 절대적 방위를 기준으로 추적한다. 본 논문에서는 이처럼 사람이 다른 사람의 목소리를 듣고 반응하거나 어떤 방향으로 가고자할 때 소리가 나는 방향이나 지도를 통해 대략 자신만의 방위를 만드는 것에 착안하여, 지능형 모바일 로봇에 음원추적 장치와 전자나침반을 장착함으로써 음원의 방향 또는 절대 방위를 기준으로 목표물을 찾아가는 알고리즘을 제시하고자 한다.

• Journal of Positioning, Navigation, and Timing
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• 제1권1호
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• pp.35-43
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• 2012

The UGV is one of the special field robot developed for mine detection, surveillance and transportation. To achieve successfully the missions of the UGV, the accurate and reliable navigation data should be provided. This paper presents design and implementation of multi-sensor-based open architecture integrated navigation for localization of UGV. The presented architecture hierarchically classifies the integrated system into four layers and data communications between layers are based on the distributed object oriented middleware. The navigation manager determines the navigation mode with the QoS information of each navigation sensor and the integrated filter performs the navigation mode-based data fusion in the filtering process. Also, all navigation variables including the filter parameters and QoS of navigation data can be modified in GUI and consequently, the user can operate the integrated navigation system more usefully. The conventional GPS/INS integrated system does not guarantee the long-term reliability of localization when GPS solution is not available by signal blockage and intentional jamming in outdoor environment. The presented integration algorithm, however, based on the adaptive federated filter structure with FDI algorithm can integrate effectively the output of multi-sensor such as 3D LADAR, vision, odometer, magnetic compass and zero velocity to enhance the accuracy of localization result in the case that GPS is unavailable. The field test was carried out with the UGV and the test results show that the presented integrated navigation system can provide more robust and accurate localization performance than the conventional GPS/INS integrated system in outdoor environments.

• 한국산학기술학회논문지
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• 제11권2호
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• pp.414-419
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• 2010

본 논문은 호버링 무인잠수정 'NOAH'의 설계과정을 언급하였고 그 성능을 확인하기 위한 수학모델을 정립하고 실험을 실시하였다. 시뮬레이션과 수조실험을 통해 성능을 검증하였으며, 무인잠수정 NOAH의 설계목표인 자세 및 위치제어를 위한 기본실험을 실시하였다. 설계된 무인잠수정은 일반적인 ROV형태의 외형을 갖고 있으며, 이러한 외형은 NOAH의 제작목적에 따라 다양한 장비를 설치하여 실험하기가 용이하며 크기는 $0.75m{\times}0.5m{\times}0.5m$이다. 추진을 위한 450watt의 용량을 갖는 4개의 추진기가 주행방향, 횡방향, 수직방향으로 설치되어져 있고 수심을 측정하기 위한 압력센서와 방향각을 측정하기 위한 자력컴파스가 설치되었다. 잠수정의 주행을 제어하기 위해 펜티엄 III의 소형 온보드 컴퓨터에 운영체제는 윈도우 XP를 탑재하였다. 제작된 호버링 무인잠수정 NOAH는 다양한 환경에서 여러 가지 제어알고리즘을 적용하여 성능을 개선하고 실험을 하기 위한 테스트베드로 운영된다.

• Journal of Oral Medicine and Pain
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• 제19권1호
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• pp.137-149
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• 1994

This study was performed to investigate the relationship between Forward Head Posture(FHP) and Craniomandlbular Disorders(CMDs). Many studies reported that there was some relationship between them, however, there is still controversy. So It Is necessary to observe and compare many more patients with CMDs wirh normal controls. For the study 85 patients with CMDs and 37 dental students were selected as experimentals and controls, respectively. And the experimentals were classified Into two groups, that is, TMJ internal derangement group and muscle disorders group according to clinical diagnosis. For measuring the FHP, CROM(Cervical-Range-of-Notion)was used. This goniometer is composed of three part. First, gravity goniometer for flexion and extension. Second, magnetic compass and yoke for rotational movement. And last, forward head arm and vertebra locator for forward head posture. Next T-Scan, electronic occlusal analyzer, was used for recording of occlusal contact state. Other items such as maximum opening, lateral excursion, Helkimo's anamnestic index, and muscle palpation point from Friction's craniomandibular index were checked clinically by one examiner. The result of this study were as follows : 1. In male, control group showed much more measurement in resting forward head posture than did experimental group. But there were not significant differences between groups in female subject. From this results, the author contended that CROM is new measuring system and differ from other goniometers in some aspect, so that results should be re-evaluated 2. Mean value of maximum mouth opening in nearly all groups were greater than 40mm. and mouth opening had a significant correlation with occlusal force and with anamnestic index both sex. 3. Mean value of palpation point had not any correlationship with forward head posture in both sex, but there was significant difference between upper and lower group by rounded shouldes. 4. In summary, there was no significant relationship between forward head posture and sign and symptom of Craniomandibular Disorders.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.181-184
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• 2016

본 연구는 선박의 위치 및 선내 화물/장치들의 이동으로 인한 자차수정 값의 변화에 따른 부정확성을 보완하고, 수작업의 불편함을 해소하기 위해 자차수정 방법 간편화 및 자동화를 통해 시켜 수정 값의 정확성과 수정의 편의성을 도모한 연구로써 사용된 주된 방식은 자차수정을 위한 자동 변환 프로그램에 자기컴퍼스 선수방향 신호를 자동 또는 수동 입력하여 자차수정 값을 자동 도표화 하는 것으로 24방위를 기본 측정방위로 하였으며 측정된 값은 데이터 및 도표로 전시되어 정확한 자차수정 값 산출이 가능하게 하였고 이를 통해 전문가에 의한 자차수정 불필요로 자차수정 시간/장소 및 비용 감소 등의 효과를 얻을 수 있어 전 세계 모든 지역(해상/육상/항공)에서 비전문가의 별도 자차수정 작업없이 ${\pm}3^{\circ}$이내 오차 범위 내에서 자차표 작성이 가능하여 자이로컴퍼스 사용 불가시 또는 제한시 항해안전 도모 등 선박 경제성과 안전성 측면에 많은 도움을 줄 것이다.

• 한국해양공학회지
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• 제18권4호
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• pp.33-39
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• 2004

This paper presents a hybrid underwater navigation system for unmanned underwater vehicles, using an additional range sonar, where the navigation system is based on inertial and Doppler velocity sensors. Conventional underwater navigation systems are generally based on an inertial measurement unit (IMU) and a Doppler velocity log (DVL), accompanying a magnetic compass and a depth sensor. Although the conventional navigation systems update the bias errors of inertial sensors and the scale effects of DVL, the estimated position slowly drifts as time passes. This paper proposes a measurement model that uses the range sonar to improve the performance of the IMU-DVL navigation system, for extended operation of underwater vehicles. The proposed navigation model includes the bias errors of IMU, the scale effects of VL, and the bias error of the range sonar. An extended Kalman filter was adopted to propagate the error covariance, to update the measurement errors, and to correct the state equation, when the external measurements are available. To illustrate the effectiveness of the hybrid navigation system, simulations were conducted with the 6-d.o.f. equations of motion of an AUV in lawn-mowing survey mode.

• 한국항해항만학회지
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• 제33권1호
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• pp.35-41
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• 2009

워터젯이 탑재된 RIB(Rigid Inflatable Boat)형태의 무인수상선을 인한 경유점 추적 제어 알고리즘을 설계하였고, 성능 검증을 위해 실해역 시험을 수행하였다. 본 연구에서 사용된 RIB형 무인수상선의 경유점 추적제어를 위해서는 방향제어를 위해 버킷각을 제어하여야 한다. 우선, 육상 관제소에 미리 입력된 경유점들의 위경도 등의 위치정보들을 바탕으로, 목표 방향각을 실시간 계산한다. 그리고, 무인수상선에 탑재된 마그네틱 콤파스 등의 센서로부터 받은 선수각 및 선수각속도의 값과 PD 제어기법을 이용하여, 버킷각 명령을 실시간 계산한다. 본 연구에서는, 바람 등의 외력으로 인한 표류각을 보정하기 위해 일정속도 이상에서는 실침로(Course Of Ground, COG)를 사용하였다. 또한, 설계된 경유점 추적 제어 알고리즘을 검증하기 위해 부산 광안대교 근처 해역에서 육상관제소를 설치하고, 실선 시험을 수행하였다. 본 논문에서는, 설계된 무인 경유점 추적 제어 알고리즘의 시험결과를, 유인으로 제어한 결과 및 상용추적제어기로 제어한 결과들과 비교 분석하였다.

• 대한지리학회지
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• 제47권1호
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• pp.60-78
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• 2012

본 연구는 성호의 대표 저작인 [성호사설]의 만물문(萬物門)에서 지리관련 내용을 뽑고, 오늘날 지리학 분류체계와 개념을 기준으로 해석하면서 성호의 '지리적 관심과 사고(思考)'를 알아보려 한 것이다. 결과는 첫째, 지반의 융기, 회오리 바람, 토양성질, 윷 말판의 천문지리 등 자연지리 내용과 산삼, 담배, 고추, 전통과실(밤 대추 감), 고려지(高麗紙; 한지), 뽕나무와 목면, 천연 염색, 마정(馬政), 지남침, 모내기 농구 앙마(秧馬) 등 인문지리 내용이 나타난다. 둘째, 회오리 바람, 지남침, 말[馬], 고추, 산삼, 전통과실(대추 밤), 사도(柶圖; 윷판) 등의 내용은 자세하고 깊다. 셋째, 철저한 고증과 인용을 바탕으로 기술하여 내용의 진위(眞僞)는 대체로 '진(眞)'이다. 넷째, 많은 주제와 내용들이 '서민들의 민생경제 및 그 개선'에 주안을 둔다. 농작물 관련내용과 말을 이용한 물자 수송 등에 주된 관심을 기울여 당시의 시대적 상황을 반영한다. 다섯째, 모든 설명에 대한 고증과 인용은 중국(청) 문헌을 토대로 하는 것을 볼 때, 조선에 대해 당시 청(淸)은 선진세계이며 본받을 만한 문명 문물이었다. 여섯째, 말의 정책적 관리, 모내기 농구 앙마, 뽕나무, 옷의 천연염색 등의 내용을 제외 하면 오늘날에도 효용성이 있는 유용한 내용들이다. 요약컨대 성호의 지리적 관심과 사고(思考)는 민생 농업경제에 초점이 모아짐을 알수 있다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.5019-5024
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• 2015

Background: The purpose of this study was to assess the dosimetric and clinical feasibility of volumetric modulated arc based hypofractionated stereotactic radiotherapy (RapidArc) treatment for large acoustic schwannoma (AS >10cc). Materials and Methods: Ten AS patients were immobilized using BrainLab mask. They were subject to multimodality imaging (magnetic resonance and computed tomography) to contour target and organs at risk (brainstem and cochlea). Volumetric modulated arc therapy (VMAT) based stereotactic plans were optimized in Eclipse (V11) treatment planning system (TPS) using progressive resolution optimizer-III and final dose calculations were performed using analytical anisotropic algorithm with 1.5 mm grid resolution. All AS presented in this study were treated with VMAT based HSRT to a total dose of 25Gy in 5 fractions (5fractions/week). VMAT plan contains 2-4 non-coplanar arcs. Treatment planning was performed to achieve at least 99% of PTV volume (D99) receives 100% of prescription dose (25Gy), while dose to OAR's were kept below the tolerance limits. Dose-volume histograms (DVH) were analyzed to assess plan quality. Treatments were delivered using upgraded 6 MV un-flattened photon beam (FFF) from Clinac-iX machine. Extensive pretreatment quality assurance measurements were carried out to report on quality of delivery. Point dosimetry was performed using three different detectors, which includes CC13 ion-chamber, Exradin A14 ion-chamber and Exradin W1 plastic scintillator detector (PSD) which have measuring volume of $0.13cm^3$, $0.009cm^3$ and $0.002cm^3$ respectively. Results: Average PTV volume of AS was 11.3cc (${\pm}4.8$), and located in eloquent areas. VMAT plans provided complete PTV coverage with average conformity index of 1.06 (${\pm}0.05$). OAR's dose were kept below tolerance limit recommend by American Association of Physicist in Medicine task group-101(brainstem $V_{0.5cc}$ < 23Gy, cochlea maximum < 25Gy and Optic pathway <25Gy). PSD resulted in superior dosimetric accuracy compared with other two detectors (p=0.021 for PSD.