• 제목/요약/키워드: Field experimental study

검색결과 3,687건 처리시간 0.032초

직파재배 논의 지표관개 수리특성 -건답휴립직파 논을 중심으로- (Hydraulic Characteristics of Surface Irrigation in Paddy Field of Direct Seeding Culture -With paddy field of ridge direct dry seeding-)

  • 정하우;최진용;김대식;박기욱;배승종
    • 한국농공학회지
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    • 제39권4호
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    • pp.64-74
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    • 1997
  • The purpose of this study is to analyze hydraulic characteristics of surface irrigation in a paddy field of direct seeding culture. Field experiment was performed in the paddy field of ridge direct dry seeding. Simulation by a numerical model was also accomplished with the data obtained from the field experiment. The model was developed by one dimensional zero-inertia equation and finite difference method. From the result of the field observation, the furrows of the experimental field were found to have various geometric characteristics. Advance distance and time were measured both in the field and by the model simulation for various furrow lengths and irrigation discharges. Roughness coefficients of each furrow were also estimated by the model.

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Design Considerations to Enhance Perforation Corrosion and Life Prediction of Automotive Body Panel

  • Choi, Minsoo;Chung, Bumgoo;Choi, Jaewoong
    • Corrosion Science and Technology
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    • 제2권5호
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    • pp.247-251
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    • 2003
  • The corrosion forms of automotive body panels are various. One of the representations is a corrosion pitting and its propagation on the lapped portion by galvanic corrosion. But it has been difficult in correlation analysis about the corrosion propagation rate and mechanism of pitting and the actual automotive body in field. This present study interprets experimentally the rust pitting occurrence mechanism on the lapped panels through experimental methods. And field car investigation was executed for correlation analysis with experimental results. This paper compares corrosion propagation rate by pitting on hot-dip galvannealed steel sheets with corrosion forms in the automotive field condition. The research fundamentals which make it possible to predict the pitting occurrence and propagation on the lapped panels in the actual vehicles are given.

Gray Scale Plasma Display Panel with a New High-Speed Drive

  • Ryeom, Jeong-Duk
    • 조명전기설비학회논문지
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    • 제21권9호
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    • pp.7-11
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    • 2007
  • The objective of this study is to evaluate the characteristics of a newly proposed high-speed drive method for the gray scale display for high-resolution plasma display panels(PDP). In the experiment it was found that the characteristics of gray scale display are not closely affected by a priming period below 50[${\mu}s$], the width of the priming period, and that it can be driven stably from the brightest sub-field to the darkest sub-field even though a priming discharge is applied to the 1 TV-field only once. Moreover, from the experimental result, the gray scale pattern of 8-bit and 9 sub-fields was stably displayed in the experimental PDP with scan pulses having the pulse width of 0.7[${\mu}s$]. An address voltage margin of about 25[V] and a sustain voltage margin of about 10[V] was obtained.

다공관 출구로부터 방출되는 펄스파에 관한 실험적 연구 (An Experimental Study on the Impulse Wave Discharged from the Exit of a Perforated Pipe)

  • 허성욱;이동훈;김희동
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2003년도 제20회 춘계학술대회 논문집
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    • pp.67-71
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    • 2003
  • The propagation characteristics of the impulse wave discharged from the exit of a perforated pipe is investigated through a simple shock tube facility. The pressure histories and directivities of the impulse wave propagating outside from the exit of pipe with several different configurations are analyzed for the range of the incident weak shock wave Mach number between 1.02 and 1.2. In the shock tube experiments, the impulse wave are visualized by a Schlieren optical system for the purpose of understanding its propagation characteristics. The experimental results show that for the near sound field the impulse noise strongly propagates toward to the pipe axis, but for the far sound field the impulse noise uniformly propagates toward to the omnidirections, indicating that the directivity pattern is almost same regardless of the pipe type. Especially, it is shown that the perforated pipe has a little performance to reduce the impulse noise only for the near sound field

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광탄성 실험에서 균열선단 응력장의 고차항을 고려한 응력확대계수 측정에 관한 연구 (A Study on the Measurement of Stress Intensity Factor Considering of High Order of Stress Field in the Vicinity of Crack Tip by Photoelastic Experiment)

  • 서재국
    • 한국안전학회지
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    • 제15권1호
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    • pp.43-52
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    • 2000
  • Generally, photoelastic experimental data were measured in the closed vicinity of crack tip to determine stress intensity factors of a crack with photoelastic experiment method. In this case, only the first order term has been considered in the equation of stress field. But because it is very difficult to measure the correct photoelastic data in the closed vicinity of crack, the accuracy of experimental results was very poor. By including the high order terms in the stress field equation we could obtain the accurate S.I.F values by using clear photoelastic data in the distant region from crack tip instead of unclear photoelastic data in the vicinity of crack tip.

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ER유체의 유동특성에 관한 실험적 연구 III (평행평판 간극내의 유량-압려강하 특성) (Experimental Investigation on the Flow Characteristics of ER Fluids III (3nd Report, Flow-Pressure Drop Characteristics clearance between Two Parallel Plate))

  • 김도태
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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    • pp.399-404
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    • 1999
  • Electro-rheological(ER) fluids are suspensions which show an abrupt increase in rheological properties under electric fields. The rheological response is very rapid and reversible when the electric field is imposed and/or removed. Therefore, there are many practical applications using the ER fluids. The purpose of the present study is to examine the flow characteristics of electro-rheological fluids. The field-dependent yield stress are obtained from experimental investigation on the Bingham property of the ER fluid. Then the steady relationshup between pressure drop and flow rate of the ERF was two fixed parallel-plates was measured under application of an electric fields. The electrical and rheological properties of zeolite based electro-rheological fluids were reported.

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전동기 냉각팬의 유량예측을 위한 수치해석 (A Numerical Analysis for Prediction of Flow Rate of the Motor Cooling Fan)

  • 이상환;강태인;안철오;서인수;이창준
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2005년도 연구개발 발표회 논문집
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    • pp.670-677
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    • 2005
  • In this study, we analyzed the three dimensional unsteady flow field around the motor cooling fan using the unsteady lifting surface theory. We obtained the flow rate for various geometries of fan from the calculated results of velocity field. For the data of design parameter and rotating speed(rpm) of the fan, we can predict the flow rate of the motor cooling fan with thin thickness through numerical analysis without the experimental data of the free stream velocity which is a boundary condition of flow field. the numerical results showed the flow rate within 10% of error in comparison with experimental results. The radial fans, which are often used as internal motor fan were also investigated with the same procedure.

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항암화학요법에 관한 개별교육이 암 환자의 삶의 질에 미치는 효과 (A Study on Effect of Individual Education about Chemical Therapy for Preventing Cancer on Quality of Life of Patient Who Suffers From Cancer)

  • 추연화;김경희
    • 종양간호연구
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    • 제4권2호
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    • pp.103-109
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    • 2004
  • The disease occurrence rate of the cancer is rapidly increased and It is becoming the main factor for the death The chemical therapy for preventing the cancer is recently used for many patients and thus extended the life of the patients. However, the side effect caused by the medical substances when performing the chemical therapy for preventing the cancer and the consequent mental and social problem are incurred to deteriorate the quality of the life. Therefore, it is needed to help the patient In order to reduce the above problems, and so this study was executed in order to examine the effect of the individual education on the quality of the life of the patients who are treated by the chemical therapy for preventing the cancer. The study was performed from Jan. 19. 2004 to Apr. 18. 2004 for the patients who were firstly treated by the chemical therapy for preventing the cancer in a university hospital located in the downtown in Seoul. The individual education on the chemical therapy for preventing the cancer was provided to 40 patients of the experimental group. The study plan is the experimental plan before and after the sole group, and it is the beginning experimental plan. The title of the booklet on the chemical therapy for preventing the cancer is "Cancer, The more you know, the more you can be cured", and the book was composed up of the side effect of the chemical therapy for preventing the cancer, treatment way for the side effect, and guide of the daily life. The survey with the questionnaire sheet was distributed to the experi- mental group before the education, the survey sheet was made out when they were hospitalized for 3-4 weeks after the education, and the data were examined by using SPSS statistical program with making our the survey questionnaires and the change of the quality of the life before and after the education of the patients who are treated by the chemical therapy for preventing the cancer was analyzed by using the parred t-test. The research result was verified that it has the meaningful that the quality of the life for the physical field, mental field, social field, and spiritual field after the individual education. The suggestion concluded by the above research result is as follows. First, there is the limitation to interpret the result since it was the beginning experimental plan for the sole group. Thus, it is suggested that the similar experimental plan should be executed with the expansion of the research subject and also with the contrast group. Second, it is suggested that the study on the change of the quality of the lifeaccording to the support of the individual education and family of the patients who are treated by the anti-cancer therapy.

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코칭 효과 검증을 위한 현장실험연구: 코칭과 자아존중감, 진로결정자기효능감 및 진로준비행동 간의 관계 (A Field Experiments Study for Coaching Effects Verification: Relation between Coaching and Self-esteem, Career Decision Making Self-efficacy, and Career Preparation Behavior)

  • 조성진
    • 직업교육연구
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    • 제37권5호
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    • pp.101-121
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    • 2018
  • 본 연구의 목적은 현장실험을 통해 코칭과 자아존중감, 진로결정자기효능감 및 진로준비행동 사이의 관계를 밝히는 것이다. 이를 위해 4년제 대학교에 재학 중인 대학생 50명(남학생 30명, 여학생 20명)을 선정했고, 코칭 효과를 분석하기 위해 연구대상자를 25명씩 실험군과 대조군으로 나누었다. 먼저, 실험군에 속한 대학생들에게 코칭 프로그램(진로 특강과 코칭)을 진행한 후, 선행연구를 바탕으로 선정된 자아존중감, 진로결정자기효능감 및 진로준비행동 항목을 검사했다. 대조군에 속한 대학생들에게도 실험 전후에 같은 항목을 검사했다. 실험군과 대조군에 대한 코칭 전후의 차이를 비교하기 위해 IBM SPSS 22.0 프로그램을 활용하여 수집된 자료를 분석했다. 그 결과, 코칭을 진행한 후에 실험군의 자아존중감, 진로결정자기효능감 및 진로준비행동 수치가 모두 통계적으로 유의미하게 상승된 것으로 밝혀졌다. 이것은 코칭이 직장인과 일반인의 경력개발 및 관리 등에 유용하다는 선행연구를 재차 확인한 것이고, 나아가 코칭은 대학생의 진로지도 및 직업교육에도 적용될 수 있는 유효한 인적자원개발 수단임을 의미한다.

자성 유체를 이용한 1자유도 계의 공진멸소에 관한 실험적 연구 (An experimental study on resonance reduction of system with one degree of freedom by magneticfluid)

  • 전운학;이봉규;황승식;이희상;김중
    • 한국자동차공학회논문집
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    • 제7권9호
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    • pp.131-137
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    • 1999
  • Under magnetism , as the magneticfluid is being itself magnetized, increase the apparent viscosity because of its body force and has the magnetic characteristics in response ot magnetism, the magnetic fluid is getting attention in various field. The magnetic fluid has the fluidity, which is a special characteristics of fluid and the magneticism , which is a special one of solid. Using this characteristics, this study has been proceeded to show the basic data for developing of a viscous damper with magnetism fluid as hydraulic fluid. Experimental study shows that the application of magnetic field is effective reducing the resonance characteristics of the spring-mass system.

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