• Defense and Technology
• /
• no.8 s.270
• /
• pp.56-67
• /
• 2001

일반적으로 보병병사의 취약점은 첫째 위치가 탐지 당하면 방어수단의 미비로 지원화력에 의해 즉각 피해를 당할 수 있고, 둘째 보병의 무기는 전정에서 다른 무기와 비교하여 위력이 약하고 명중률이 낮으며 시계의 한계를 벗어나기 곤란하며 전투 중 병사는 동료와 지휘관으로부터 고립되기 쉽다는 사실이다. 이러한 문제점을 해결하기 위해 혁신적으로 발전하는 과학기술의 적용으로 다양한 파장영역의 센서, 고속 컴퓨터, 자동화 병기, 그리고 최첨단 기재에 의해 초능력 병사가 출현할 가능성이 높아지고 있다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.2
• /
• pp.865-871
• /
• 2011

Presently, the location and direction information are certainly needed for the autonomous vehicle of the ship. Among them, the direction information is a essential elements to automatic steering system. And the gyro-compass, the magnetic-compass and the GPS compass are the sensor indicating the direction. The gyro-compasses are mainly used in the large-sized ship of the GMDSS(Global Maritime Distress & Safety System). The precision and the reliability of the gyro-compasses are excellent but big volume and high price are disadvantage. The magnetic-compass has relatively fine precision and inexpensive price. However, the disadvantage is in the influence by the magnetism object including the steel structure of a ship, and etc. In the case of the GPS compass, the true north is indicated according to the change of the location information but in case of the minimum number of satellites or stopping of a ship or exercise in the error range, the exact direction cannot be obtained. In this paper, the performance of the GPS compass was improved by using the least-square curve fitting method for the mutual trade off of the angle sensor. The algorithm which improves the precision of an azimuth by applying the weighted value according to the size of covariance error was proposed with GPS-compass and magnetic compass. The characteristic and the performance of the proposed algorithm were analyzed and verified through experimentation. The applicability of the proposed algorithm was shown through the experimental result.

• Journal of Life Science
• /
• v.21 no.1
• /
• pp.159-164
• /
• 2011

Microbial whole-cell biosensors can be excellent analytical tools for monitoring environmental pollutants. They are constructed by fusing reporter genes (e.g., lux, gfp or lacZ) to inducible regulatory genes which are responsive to the relevant pollutants, such as aromatic hydrocarbons and heavy metals. A large spectrum of microbial biosensors has been developed using recombinant DNA technology and applied in fields as diverse as environmental monitoring, medicine, food processing, agriculture, and defense. Furthermore, their sensitivity and target range could be improved by modification of regulatory genes. Recently, microbial biosensor cells have been immobilized on chips, optic fibers, and other platforms of high-throughput cell arrays. This paper reviews recent advances and future trends of genetically modified microbial biosensors used for monitoring of specific environmental pollutants.

• Proceedings of the KIEE Conference
• /
• 2005.07a
• /
• pp.727-729
• /
• 2005

본 논문에서는 낙뢰에서 발생하는 VHF 대역의 신호를 광대역 간섭계를 통하여 낙뢰의 방전경고 측정하는 거리 낙뢰관측 시스템을 소개하고자 한다. 측정시스템은 3개의 광대역 전계센서와 LF/VLF 대역의 전계센서로 구성된다. 측정된 신호는 잡음 제거를 위한 필터를 거쳐 디지털 신호로 변환되어 메모리에 저장되어 진다. 각각의 센서로부터 측정된 신호는 FFT분석을 거쳐 신호원인 낙뢰의 방위각과 고도각이 계산되어진다. 이 시스템은 30 km 내외의 뇌운의 방전 경로의 형성과 진전과정을 세밀하게 관측할 수 있다.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1996.11a
• /
• pp.177-182
• /
• 1996

Remote nuclear cask handling device (RNCHD)는 사용후 핵연료cask의 원격 조작에 있어서 안전성과 성능을 향상을 목적으로 한다. RNCHD의 한부분인 grapple은 사용후 핵연료cask의 이동 및 수송 또는 용기뚜껑의 개폐를 위하여 cask의 벽에 대각선으로 돌출되어있는 두 개의 trunnion에 삽입되어야한다. 그러나 trunnion으로의 grapple 삽입은 용기중심과 grapple 장치 중심사이의 위치와 방향편차 때문에 어렵게된다. 인공신경망은 grapple에 설치된 광전센서를 사용하여 용기의 중심으로 부터 grapple 장치의 상대적 위치를 계측하기위해 사용된다. 인공신경망 학습은 광전센서값과 grapple의 상대적 위치와 방향사이의 함수적 관계를 추론하기 위해 수행된다. 이렇게 측정된 RNCHD의 중심위치는 grapple의 자세를 맞추기 위한 제어입력값으로 제공된다. 인공신경망 학습을 위한 데이터는 grapple 장치와 trunnion을 모사한 1/2 스케일의 실험장치를 사용함으로써 얻어진다. 학습된 인공신경망은 학습에 사용 안된 센서입력값, 즉 새로운 grapple의 위치에 대해서도 정확성을 가지고 grapple 장치의 위치와 방위를 측정할 수 있었다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.12
• /
• pp.1207-1215
• /
• 2013

This paper proposes the location estimation techniques of distributed targets with the multi-sensor data perceived through IR sensors of the military robots in consideration of obstacles. In order to match up targets with measured azimuths, to add to the depth-first search (DFS) algorithms in free-obstacle environment, we suggest the expanded DFS (EDS) algorithm including bypass path search, partial path search, middle level ending, and the supplementation of decision metric. After matching up targets with azimuths, we estimate the coordinate of each target by obtaining the intersection point of the azimuths with the least square error (LSE) algorithm. The experimental results show the error rate of estimated location, mean number of calculating nodes, and mean distance between real coordinates and estimated coordinates of the proposed algorithms.

• The Journal of the Acoustical Society of Korea
• /
• v.41 no.6
• /
• pp.637-646
• /
• 2022

Sub-arrays of arbitrary conformal array have different geometric shape through steering direction, thus the beam patterns of sub-arrays are always non-uniform. In this paper, we apply the beam pattern synthesis method using convex optimization into the conformal array, and shows the improvement of uniformity of beam performance. The simulation is performed with the conformal array of cut-sphere shape. As a result, the standard deviation of 3 dB beamwidth in elevation is greatly reduced but the directivity index is also reduced. To alleviate this trade-off, we propose a convex optimization using a shading function.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39B no.11
• /
• pp.755-762
• /
• 2014

In recent year, along with the rapid development of LED technology, many applications using LEDs with Visible Light Communication(VLC) have been researched. Since it is easy to provide LOS communication environment along with cheap deployment cost, the indoor positioning system based on VLC has been actively studied. In this paper, we propose an accurate indoor positioning algorithm using a stereo image sensor and white-light LEDs with the visible light communication. Indoor white-light LEDs are located at the ceiling of a room and broadcast their position information by VLC technology. Mobile receiver with stereo image sensor receives LED position information by VLC and estimates its position and angle information. Simulation results are given to show the efficiency of proposed indoor positioning algorithm.

• Geophysics and Geophysical Exploration
• /
• v.23 no.2
• /
• pp.89-96
• /
• 2020

This tutorial summarizes the coordinate transforms for formulating geophysical problems. To ensure mathematical consistency, this discussion begins with the right-hand rule. Further, the concepts of active and passive transforms are introduced. By extending these concepts, the coordinate transform and its inverse between two coordinates are related to the matrix transpose. The yaw-pitch-roll rotation and the azimuth-deviation-tool face rotation transforms are described as the most frequently used schemes, and the relation between the Rodrigues' rotation formula and these two transforms are mathematically explained. The "Gimbal Lock" problem inherent in yaw-pitch-roll rotation is schematically presented and mathematically derived. As a useful tool overcome this problem, the principle and usage of the quaternion is also described.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.7
• /
• pp.2334-2340
• /
• 2010

Sun position computed by Michalsky shows maximum $1.5^{\circ}$, $0.88^{\circ}$ and 2 minutes differences in azimuth, altitude, and sunrise and sunset times respectively compared with Korean Almanac. The 2-axis solar tracking system, which consist control panel with ATmega128 CPU, BLDC motor-cylinder actuator and 2-axis link mechanism, was developed. Computed azimuth and altitude of sun for a current time, and latitude and longitude of tracker position built are controlled in real time by BLDC motor-cylinder actuators comparing with the position feed-backed by Hall sensor. The use of BLDC motor is free in maintenance. Implementation of a home-return function by Hall sensor is to minimize the cumulative error.