• Title, Summary, Keyword: magnetic exploration system

Search Result 35, Processing Time 0.042 seconds

Elimination of car's magnetic effect as noise in a car-borne magnetic exploration system (차량 자력탐사에서 차량의 영향의 제거)

  • Lim, Mu-Taek;Park, Yeong-Sue;Chung, Hyun-Key;Rim, Hyoung-Rae;Koo, Sung-Bon;Lee, Young-Chal
    • 한국지구물리탐사학회:학술대회논문집
    • /
    • /
    • pp.141-151
    • /
    • 2006
  • A blank test was done to calculatee the car itself's magnetic effect as noise and to eliminate it from the data set of total magnetic intensity(=magnetic flux density) exploration in a car-borne magnetic exploration system. To calculate the induced magnetic intensity(= magnetization) and the remanent magnetic intensity(= magnetization) of the car itself, we have installed the magnetometer on a fixed point and measured the magnetic intensity letting the car move around the magnetometer, and we have changed the data set into an analogous data set as if acquired in the condition that we have parked the car on the same fixed point and measured the magnetic intensity moving the magnetometer around the magnetometer. Through an inversion with the later data set as input, we have calculated the magnetic center and the magnetic moments of the induced magnetic intensity(= magnetization) and the remanent magnetic intensity(= magnetization) of the car itself with the two centers coincided because of some barriers of the inversion algorithm that we have used in this study. On the other hand, we have extracted the magnetic anomaly by reducing i. e. vectorially eliminating the induced magnetic intensity(= magnetization) and the remanent magnetic intensity(= magnetization) of the car itself calculated forwardly, from the magnetic exploration data set acquired by the car-borne magnetic exploration system.

  • PDF

Inversion of the Magnetic Field Generated by a Car (차량이 발생하는 자기장에 대한 역산)

  • Lim, Mu-Taek;Park, Yeong-Sue;Rim, Hyoung-Rae;Koo, Sung-Bon;Jung, Hyun-Key;Kwak, Byoung-Wook
    • Geophysics and Geophysical Exploration
    • /
    • v.11 no.4
    • /
    • pp.343-349
    • /
    • 2008
  • We have constructed a car-borne magnetic exploration system, in which a car drags a non-magnetic cart on which a magnetometer is installed. In the total magnetic field measured as a vectorial sum in this system, are included the magnetic field generated by the car itself. This magnetic field, doing the role of a magnetic noise, should be eliminated. For this purpose, we have set up a measurement condition to get the same effect as if we have put the car in one point and thereafter measured the magnetic field around it. In this case, if there is any magnetically anomalous body in the area, we can consider all the remaining magnetic field to have been generated by the car itself, once the geomagnetic field eliminated. We tried to invert the magnetic field considered to have been generated by the car and succeeded to derive the magnetic moment and the direction of the induced and remanent magnetic field of the car respectively. Once the magnetic moment and the direction of the induced and remanent magnetic field have been calculated, the magnetic field generated by them in specific points can be directly and analytically calculated. This result can be used in the future to eliminate the magnetic field generated by the car itself doing the role of a magnetic noise during the procedure of reduction of the measured magnetic exploration data by the car-borne magnetic exploration system.

A Development of Fluxgate Sensor-based Drone Magnetic Exploration System (플럭스게이트 센서 기반 드론 자력탐사 시스템 개발)

  • Noh, Myounggun;Lee, Seulki;Lee, Heuisoon;Ahn, Taegyu
    • Geophysics and Geophysical Exploration
    • /
    • v.23 no.3
    • /
    • pp.208-214
    • /
    • 2020
  • In this study, we have developed a drone magnetic exploration system (proto-type) using a fluxgate magnetic sensor. Hardware of the system consists of a fluxgate magnetometer, an inertial measurement unit (IMU), a GPS, and a communication module. And we have developed monitoring software, which enables it to transmit the measured data to the ground control system (GCS) in real time. The measured magnetic data are finally saved as 1 Hz data after passing through a notch filter and a band-pass filter. For verification of this system, a preliminary test was conducted to check the magnetic responses of a magnetic object first, then the field test was carried out in two iron mines. We tested the developed system on the field test in Pocheon, Gyeonggi and Jeongseon, Gangwon. The magnetic data from the developed drone system was very similar to those from unmanned airship system developed by Korea Institute of Geoscience and Mineral Resources (KIGAM). As a result, preliminary experiment and field test have demonstrated that this system is applicable for outdoor aeromagnetic exploration. It requires more studies to improve filter function and instrument performance to minimize noise in the future.

Some case histories to detect underwater buried objects by electrical and magnetic methods (수중 매장물 조사에 응용되는 전기 및 자기 탐사사례)

  • JUNG Hyun Key;Park Yeong-Sue;Lim Mutaek;Rim Hyoungrae
    • 한국지구물리탐사학회:학술대회논문집
    • /
    • /
    • pp.118-137
    • /
    • 2004
  • Recently underwater geophysical problems for historical relics or UXO's are raised frequently. This study includes the applicabilities and limitations of the recent underwater metal detector and domestic case stories for underwater survey by electrical and magnetic method. Direct or indirect case stories are electrical and vertical magnetic gradiometry surveys beneath Han-river bottom for planning subway tunnel, electrical exploration on lake-bottom, electrical exploration on the tidal flats using high-power transmitter, and borehole three-component magnetic and electromagnetic surveys for detecting the undersea objects. A design of potable real-time, high-speed measurement system using multi-channel array sensors is also introduced here. Further study will be focussed on practical field applications of the fast water-bottom scanning system which is lately required by actual field.

  • PDF

A Magnetic Survey on the Lake for the Detection of the Unexploded Ordnances (위험물탐지를 위한 수상 자력탐사)

  • Jo Churl-hyun;Jung Yong Hyun;Lee Hyo Jin
    • Geophysics and Geophysical Exploration
    • /
    • v.6 no.1
    • /
    • pp.23-27
    • /
    • 2003
  • A magnetic survey on the lake war carried out to explore the possible UXO (unexploded ordnance) under the water. A magnetic gradiometer with 2 magnetometer sensors was used, which measures total magnetic intensity. For the positioning of the measurement points on the water, RTK (real time kinematic) survey system was used. The theoretical responses were calculated assumming the dimension and the material of the UXO so that the detectability could be investigated. Since the areal size of the survey vessel was rather small, the influence from the magnetic material of the vessel and the other equipments such as a laptop computer was not negligible, and the influence did not remain constant during the survey due to the change of survey direction. These effects were reduced remarkably using moving average technique. The result reveals the lineament of a pipe line laid on the bottom of the lake, which can be regarded as an indirect proof of detectability of the method.

Fundamental study on sustainable treatment system of mine water using magnetized solid catalyst

  • Mukuta, Chisato;Akiyama, Yoko
    • Progress in Superconductivity and Cryogenics
    • /
    • v.21 no.2
    • /
    • pp.15-21
    • /
    • 2019
  • In the mine exploration sites, sustainable treatment system of mine water with energy saving and minimized chemical additives is required. Since most of the mine water contains highly-concentrated ferrous ion, it is necessary to study on the removal method of iron ions. We propose the system consisting of two processes; precipitation process by air oxidation using solid catalyst-modified magnetite and separation process combining gravitational sedimentation and magnetic separation using a permanent magnet. Firstly, in the precipitation process (a former process of the system), we succeeded to prepare solid catalyst-modified magnetite. Air oxidation using solid catalyst-modified magnetite using $Fe_2(SO_4)_3$ as a starting material showed high iron removal capability. Secondly, in the separation process (latter process of the system), solid catalyst-modified magnetite using $Fe_2(SO_4)_3$ as a starting material can be separated by a superconducting bulk magnet and a permanent magnet.

Research Status of Sail Propulsion using the Solar Wind

  • Funaki, Ikkoh;Yamakawa, Hiroshi
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • /
    • pp.583-588
    • /
    • 2008
  • A spacecraft propulsion system utilizing the energy of the solar wind was reviewed. The first plasma sail concept was proposed by Prof. Winglee in 2000, and that was called M2P2(mini-magnetospheric plasmapropulsion). However, the first M2P2 design adopting a small(20-cm-diamter) coil and a small helicon plasma source design was criticized by Dr. Khazanov in 2003. He insisted that: 1) MHD is not an appropriate approximation to describe the M2P2 design by Winglee, and with ion kinetic simulation, it was shown that the M2P2 design could provide only negligible thrust; 2) considerably larger sails(than that Winglee proposed) would be required to tap the energy of the solar wind. We started our plasma ssail study in 2003, and it is shown that moderately sized magnetic sails can produce sub-Newton-class thrust in the ion inertial scale(${\sim}70$ km). Currently, we are continuing our efforts to make a feasibly sized plasma sail(Magnetoplasma sail) by optimizing the magnetic field inflation process Winglee proposed.

  • PDF

The effect of gravity and hydrostatic initial stress with variable thermal conductivity on a magneto-fiber-reinforced

  • Said, Samia M.;Othman, Mohamed I.A.
    • Structural Engineering and Mechanics
    • /
    • v.74 no.3
    • /
    • pp.425-434
    • /
    • 2020
  • The present paper is concerned at investigating the effect of hydrostatic initial stress, gravity and magnetic field in fiber-reinforced thermoelastic solid, with variable thermal conductivity. The formulation of the problem applied in the context of the three-phase-lag model, Green-Naghdi theory with energy dissipation, as well as coupled theory. The exact expressions of the considered variables by using state-space approaches are obtained. Comparisons are performed in the absence and presence of the magnetic field as well as gravity. Also, a comparison was made in the three theories in the absence and presence of variable thermal conductivity as well as hydrostatic initial stress. The study finds applications in composite engineering, geology, seismology, control system and acoustics, exploration of valuable materials beneath the earth's surface.

EM Responses of Buried Conductive Pipes Calculated by 3-D Finite Element Method (3차원 FEM 모델링에 의한 수평 도전성 관로의 전자기 반응 특성)

  • Chung Ho-Joon;Jung Hyun-Key;Park Yeong-Sue;Jo Chul-Hyun
    • Geophysics and Geophysical Exploration
    • /
    • v.3 no.2
    • /
    • pp.48-52
    • /
    • 2000
  • We have calculated and analyzed the electromagnetic responses of buried conductive pipes due to a horizontal magnetic dipole source on the pound using a three-dimensional (3-D) finite element method to provide useful guidelines for designing electromagnetic pipe locator and for field operation of the system. For single buried pipe, the horizontal component and the horizontal difference of the vertical component of magnetic field show peaks above the pipe. When comparing the width of response curves of both cases around the peak, horizontal difference of vertical component of magnetic field shows much narrower peak, 2 times narrower at a half of maximum amplitude, than that of horizontal component of magnetic field. Accordingly, we can pinpoint the horizontal location of pipe on the ground more accurately by measuring the horizontal difference of vertical component of magnetic fold. Moreover, it will have a merit in determining the depth of pipe, because the equation for depth estimation is defined just above the pipe. When there are two buried pipes separated by two meters with each other, the response of horizontal difference of vertical component of magnetic field has two separate peaks each of which is located above the pipe whereas horizontal magnetic field response has only one peak above the pipe just below the transmitter. Thus, when there exist more than a buried pipe, measuring the horizontal difference of vertical magnetic field can effectively detect not only the pipe under transmitter but also adjacent ones. The width of response curves also indicates higher resolving ability of horizontal difference of vertical component of magnetic field.

  • PDF