• 제목/요약/키워드: Field Difference

검색결과 4,714건 처리시간 0.03초

전기비저항탐사에서 음의 겉보기 비저항 (Negative Apparent Resistivity in Resistivity Method)

  • 조인기;김정호;정승환;서정희
    • 지구물리와물리탐사
    • /
    • 제5권3호
    • /
    • pp.199-205
    • /
    • 2002
  • 전기비저항 탐사에서 측정되는 양은 두 전위전극 사이의 전위차이다. 이 전위차가 양일 경우에는 겉보기 비저항도 양의 값을 가지며, 음일 경우에는 겉보기 비저항도 음의 값을 나타낸다. 또한 측정되는 전위차의 부호는 전기장의 방향에 따라 좌우된다. 만약 측정방향과 전기장의 방향이 같다면, 전위차와 겉보기 비저항은 양의 값을 보이게 되며, 그 반대의 경우에는 음의 값을 나타낸다. 일반적으로 지표 전기비저항 탐사에는 측정방향과 1차 전기장의 방향이 같은 전극 배열을 사용하며, 이 방향의 1차 전기장은 2차 전기장에 비하여 항상 크다. 따라서 일반적인 전극배열을 사용하는 지표 전기비저항 탐사의 경우에는 지형이 평탄하고 잡음이 없다면 음의 겉보기 비저항은 나타나지 않는다. 그러나 시추공-시추공 전기비저항 탐사의 경우에는 1차 전기장의 방향과 측정방향이 일치하지 않으며, 경우에 따라서는 1차 전기장의 측정방향 성분이 2차 전기장의 측정방향 성분 보다 그 크기가 작을 수 있다. 이 경우 2차 전기장의 방향과 측정방향이 서로 반대일 경우에는 음의 겉보기 비저항이 나타날 수 있다. 따라서 음의 겉보기 비저항은 측정방향의 1차 전기장이 매우 작은 영역에서 발생할 가능성이 높다.

다중가진을 받는 수중 원통구조물의 방사효율에 대한 수치해석 (A Numerical Analysis on the ascoutic radiation efficiency of a stiffend cylindrical structure in underwater under multi-excitation)

  • 강명환;이종주;한승진;배수룡;정우진
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2014년도 추계학술대회 논문집
    • /
    • pp.372-376
    • /
    • 2014
  • This study is on acoustic radiation efficiency of a tiffened cylindrical model in water-multi-excitation with phase difference using commercial numerical program ABAQUS and SYSNOISE. When the stiffened cylindrical model is under multi-excitation with phase difference, the surface vibration field is variated with phase difference of excitation. By this different surface vibration field, the acoustic radiation efficiency is also variated with phase difference of excitation.

  • PDF

현장계측사례를 통한 압밀특성 평가 (Assessement of Consolidation Characteristics by Field Instrumentation)

  • 송정락;백승훈;오다영
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 1992년도 가을학술발표회 논문집
    • /
    • pp.121-130
    • /
    • 1992
  • Assessement of comsolidation characteristics of soft soil is very important in the project of soft soil improvement. In the design step, the consolidation characteristics of soil is determined by the laboratory tests (typically oedometer test), generally. But there is big differences between the condition of laboratory test and the condition of field(in situ). the differences results in the considerable difference between the predicted and measured consolidation behavior. This article analyzed the consolidation data of the "SOFT SOIL IMPROVEMENT PROJECT of the 2nd Namdong Industrial Complex at Inchon". The project was improving the road way net work in the 2nd Namdong Industrial Complex by preloading and sand pile method. Field instrumentation was performed at 10 points which consist of pneumatic piezometers, magnetic probe extensometers, inclinometers and electronic dipmeter. The results showed that there is big difference in the laboratory predicted consolidation behavior and field consolidadion behavior. Also there was big difference in the settlement behavior and pore pressure behavior. This article investigated the above factors by comparing the settlement, pore pressure and strength at different conditions.onditions.

  • PDF

Difference field 개념의 경계적분방정식을 이용한 3차원 정자장 해석 (3-D Magnetostatic Field Calculation by a Boundary Integral Equation Method using a Difference Field Concept)

  • 박민철;김동훈;박일한
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2000년도 하계학술대회 논문집 B
    • /
    • pp.903-905
    • /
    • 2000
  • For an accurate analysis of three dimensional linear magnetostatic problems, a new boundary integral equation formulation is presented. This formulation adopts difference magnetic field concept and uses single layer magnetic surface charge as unknown. The proposed method is capable of eliminating numerical cancellation errors inside ferromagnetic materials. In additions, computing time and storage memory are reduced by 75% in comparison with the reduced and total scalar potential formulation. Two examples are given to show its efficiency and accuracy.

  • PDF

비정상 흐름-파랑 공존장의 인공어초 침하특성에 관한 연구 (A Study of Artificial Reef Subsidence in Unsteady Flow-Wave Field)

  • 윤상준;김헌태
    • 한국해양공학회지
    • /
    • 제15권3호
    • /
    • pp.28-34
    • /
    • 2001
  • The experimental studies for the artificial reef (AFR) subsidence characteristics in the unsteady flow field and in the unsteady flow-wave field were carried out. The difference of scou $r_sidence characteristics between in the steady flow field and in the unsteady flow field wad discussed and also the long-term subsidence characteristics in the unsteady flow field were investigated. AFR subsidence characteristics was discussed with Keulegan - Carpenter number(KC), Reynolds number (Re),. Shields number (Sn) and dimensionless time (t/Tt). And the difference of subsidence characteristics between in the unsteady flow and in the unsteady flow-wave field was discussed.ed.

  • PDF

비정상 흐름-파랑 공존장의 인공어초 침하특성에 관한 연구 (A Study of Artificial Reef Subsidence in Unsteady Flow-Wave Field)

  • 윤상준;김헌태
    • 한국해양공학회지
    • /
    • 제15권3호
    • /
    • pp.29-29
    • /
    • 2001
  • The experimental studies for the artificial reef (AFR) subsidence characteristics in the unsteady flow field and in the unsteady flow-wave field were carried out. The difference of scour/subsidence characteristics between in the steady flow field and in the unsteady flow field wad discussed and also the long-term subsidence characteristics in the unsteady flow field were investigated. AFR subsidence characteristics was discussed with Keulegan - Carpenter number(KC), Reynolds number (Re),. Shields number (Sn) and dimensionless time (t/Tt). And the difference of subsidence characteristics between in the unsteady flow and in the unsteady flow-wave field was discussed.

간호조직의 관리적 특성과 조직 유효성의 관계 (The Relationship between Managerial Characteristics of the Nursing Organization and Organizational)

  • 최정;하나선;박정원
    • 간호행정학회지
    • /
    • 제9권4호
    • /
    • pp.625-639
    • /
    • 2003
  • Purpose: The Purpose of this study was to identify the relationship between managerial characteristics of the nursing organization and organizational effectiveness. Method : The data were gathered from the self-reported questionnaires of 717 nurses who work for eight different general hospitals located around Seoul and Kyounggi province. The period of data collection was from December 12 to December 7, 2002. For data analysis, descriptive statistics, Pearson correlation coefficient, t-test, and ANOVA with SAS & SPSS Program were used. Result : 1) Managerial Characteristics of the Nursing Organization were positively related to all of the organizational effectiveness. Transactional leadership were negatively related to all of the organizational effectiveness. 2) 'Shared Value' and 'Communication' showed a significant difference except religion. 'Autonomy' showed a significant difference except religion, major field of practice. 'Job Motivation' showed a significant difference except marital status, religion. 'Transformational leadership' showed a significant difference except marital status, religion, major field of practice. 3) 'Job satisfaction' showed a significant difference except religion, major field of practice. 'Organizational commitment' and 'Organizational citizenship behavior' showed a significant difference except religion. Conclusion : From the above results, the highly perceived with managerial characteristics of the nursing organization is very implicative to enhance the organizational effectiveness.

  • PDF

도형의 변환학습의 순차성 고찰 (A Study of the Sequence of Figure Transformation Learning)

  • 박성택
    • 한국수학교육학회지시리즈A:수학교육
    • /
    • 제17권2호
    • /
    • pp.1-13
    • /
    • 1979
  • This study aimed at studying the sequence of the Figure Transformation Learning, inquiring relationship among these transformations and then researching whether there is the difference of the learning ability or not between by teaching them as it is independent and by teaching them as it is contains. (Hypothesis 1) It may be more effective to teach The Sequence of Transformation Learning by beginning with peculiar field, ending with general field than vice versa At the result of verification-C $R_{M}$=2.59, 0.005$R_{M}$=5.19, p<0.005-significant difference appeared. It is proved more effective to teach the Figure Transformation Learning the way it contains than the way it is independent. Synthesizing two hypothesises of the above, the conclusion is following The Figure Transformation Learning should be taught by beginning with peculiar field. ending with general field (congruent transformationlongrightarrowsimilar transformationlongrightarrowprojective transformationlongrightarrowtopological transformation). To teach it the way it contains is more effective.ive.

  • PDF

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

  • 정호준;정현기;박영수;조철현
    • 지구물리와물리탐사
    • /
    • 제3권2호
    • /
    • pp.48-52
    • /
    • 2000
  • 저주파수 전자탐사 관로 탐지기 개발 및 현장 운용시의 지침을 마련하기 위해 3차원 유한요소법을 이용해서 수평 자기 쌍극자 송신원에 의한 도전성 지하 매설 관로의 전자기 반응을 계산하고 그 특성을 분석하였다. 단일 관로의 전자기 반응은 수평 자기장 및 수직 자기장의 수평 차분치 모두 관로 직상부에서 최대값을 나타낸다. 반응 곡선에서 최대값의 1/2이 되는 위치의 폭은 수평 자기장의 경우 수직 자기장의 수평 차분치보다 2배 정도 넓으며, 이는 수직 자기장의 수평 차분치가 관로 위치 분해능이 높은 것을 의미한다. 그리고 관로의 심도 계산식이 관로의 직상부에서만 정의되기 때문에 분해능이 높은 수직 자기장의 수평 차분치를 측정하는 것이 관로 심도 결정시 유리할 것이다. 서로 2 m 떨어진 이중 관로의 전자기 반응은 수직 자기장의 수평 차분의 경우 송신기 하부 및 인접 관로의 상부 모두에서 반응 곡선의 피크가 보인다. 이에 반해 수평 자기장의 경우는 인접 관로에 의한 자기장은 송신기 하부 관로에 의한 자기장에 의해 상쇄되어 송신기 하부 관로에 의한 피크만 나온다. 이로 미루어 볼 때 지하에 다수의 관로가 인접하여 매설되어 있는 상황에서는 수직 자기장의 수평 차분을 측정함으로써 다수 관로의 탐지도 가능할 것으로 보인다. 그리고 반응 곡선의 폭을 비교할 때, 단일 관로에서와 마찬가지로 분해능은 수직 자기장의 수평 차분치를 측정하는 것이 수평 자기장을 측정하는 것에 비해 뛰어난 것으로 판단된다.

  • PDF

산업 안전을 위한 시각영역에 관한 연구 (A Study of Visual Field for Industrial Safety)

  • 윤훈용;심정훈
    • 산업경영시스템학회지
    • /
    • 제25권3호
    • /
    • pp.9-15
    • /
    • 2002
  • Due to the inconsiderateness of human capability and inappropriate arrangement of display and control unit at the industrial site, the human error leads to a various accidents. This study was performed to investigate the visual range at the eye field and stationary field at the various angles with three different visual stimuli of alphabetic character, color slip and light-emitting diode. Three kinds of various alphabetic characters depending on length and breadth ratio (1:1, 3:5, 5:3) and three different colors (red, yellow, green) were used for the stimuli. Twenty-five subjects (11 males and 14 females) participated for this study. The results showed that female had wider visual range than male at the eye field, however no significant difference was found at the stationary field. The light-emitting diode had a widest visual range then color slip and characters are in order at the eye field and stationary field. For the character stimulus, the widest visual range was shown at length and breadth ratio of 1:1. The other ratios (3:5 and 5:3) showed no significant difference. The color of red had a widest visual range on the light-emitting diode, however, the color of yellow showed a widest visual range on the just color slip at the eye field. The result of this study would be valuable in applying to the design of visual display and the panel layout of control and displays in the industrial site.