• Title/Summary/Keyword: field performance

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The Mathematical Modelling of the Field Performance of Machines (기계화 농작업 성능의 수학적 모델링)

  • 김학규;정창주
    • Journal of Biosystems Engineering
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    • v.21 no.3
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    • pp.357-371
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    • 1996
  • An assessment of the field performance of machines for varied farming conditions may be essential to the development of mechanization program and rational machinery management. The field performance of machines is largely affected by the field capacity of machinery selected, physical size and shape of field plots and their scatterness, farming functions and conditions, and labor requirement and constraints. The study was to develop the mathematical model for the field performance of machines and time requirement of the rice farming systems, considering those factors which affect the field performance of machines. The mathematical models developed were simulated to determine field efficiency and capacity of the different sizes of major machinery for a various size of paddy field plot and for prevailing conditions of farming operations. The effects of the sises of machinery and the plot geometry on the efficiency and field capacity were compared for major rice farming functions.

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Comparison between CFD analysis and experiments according to various PEMFC flow-field designs (유로 형상 변화에 따른 CFD 해석 결과와 PEM 연료전지 성능 비교)

  • Lee, Kang-In;Park, Min-Soo;Lee, Se-Won;Chu, Chong-Nam
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.572-575
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    • 2008
  • Flow-field design has much influence over the performance of proton exchange membrane fuel cell (PEMFC) because it affects the pressure magnitude and distribution of the reactant gases. To obtain the pressure magnitude and distribution of reactant gases in four kinds of flow-field designs without additional measurement equipment, computational fluid dynamics (CFD) analysis was performed. After the CFD analysis, the performance values of PEMFC according to the flow-field configurations were measured via a single cell test. As expected, the pressure differences due to different flow-field configurations were related to the PEMFC performance because the actual performance results showed the same tendency as the results of the CFD analysis. A large pressure drop resulted in high PEMFC performance. So, the single serpentine configuration gave the highest performance. On the other hand, the parallel flow-field configuration gave the lowest performance because the pressure difference between inlet and outlet was the lowest.

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Paramedic student's awareness and performance of infection control on clinical field training (응급구조(학)과 학생들의 임상현장실습 시 감염관리에 대한 인지도와 수행도)

  • HuiJeong Kim;YuJin Lee;HyeonJin Choi;Seo Young Yim;Eun-Sook Choi
    • The Korean Journal of Emergency Medical Services
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    • v.28 no.1
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    • pp.47-62
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    • 2024
  • Purpose: This study aimed to provide basic data for infection control education plans based on infection control awareness and performance of paramedic students during clinical field training. Methods: Data were collected from paramedic students with experience in clinical field training. The data collection period was from May 4, 2023, to June 4, 2023, and 132 copies of the collected survey were analyzed using the SPSS27.0 program. Results: Infection control awareness and performance were 4.80±0.24 points and 4.49±0.55 points out of 5, respectively. The infection control awareness of the participants according to clinical field training-related characteristics differed significantly in university education before clinical field training (t=2.100, p=.038). In addition, there were significant differences in performance in the number of clinical field training sessions (F=9.149, p=.000), hospital education before clinical field training (t=5.365, p=.000), and hospital education during clinical field training (t=3.094, p=.002). Conclusion: Before clinical field training, schools should provide infection control education that combines theory and practice suitable for hospital practice so that students can complete the infection control education organized by the hospital. Furthermore, if a university develops infection control in the clinical field training guidelines, it will have a positive impact on students' infection control performance through prior education.

Field Performance Evaluation of Preventive Maintenance Methods (예방적 유지보수 공법의 현장 적용성능 평가 연구)

  • Lee, Sang Yum
    • International Journal of Highway Engineering
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    • v.19 no.2
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    • pp.103-112
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    • 2017
  • PURPOSES : In this study, field performance evaluation of crack treatment of pavement and the feasibility of surface treatment of pavement are presented. The performance and cost of preventive maintenance methods have been previously verified, and the methods are being used in many developed countries and cities. However, the performance and cost of the system have not been verified in domestic, field applications. Therefore, in order to improve performance, the field performance is evaluated, and a reasonable cost is proposed. METHODS : Visual Inspection was conducted to evaluate the field application and performance of the preventive maintenance method. In addition, the PCI index was calculated from the results of visual inspection of the application area of the surface treatment method, and the performance life of each method was predicted. For the economic evaluation, life cycle cost analysis was performed using the life cycle cost analysis program. RESULTS :In order to evaluate and quantify the field performance of crack repair material, the residue condition of the pavement surface after crack treatment, rather than the performance of the material, is evaluated. In addition, the crack resistance and performance life of surface treatment methods are evaluated. The cost of currently available treatment methods are compared to the common pavement cut and overlay method, and it is determined that the preventive method is not economical based on life cycle cost analysis. CONCLUSIONS :Because of the characteristics of cracking, it is necessary to conduct the evaluation of currently applied methods and the analysis of the cause of damage, by visual inspection. Moreover, in order to evaluate the performance and economic suitability of the currently applied surface treatment methods, it is necessary to acquire information on application sections by monitoring their long-term conditions and performance.

PERFORMANCE OF A 4-W TRACTOR IN THAILAND FIELD CONDITIONS

  • Kanoksak, Eam-O-Pas
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.506-512
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    • 2000
  • Performance of a four- wheel tractor fabricated by Tongyang Moolsan Co., Ltd, Korea was tested in Thailand during May-June 2000. Wheel slip and field capacity were measured in three fields using different traction devices and implements. The tractor worked satisfactorily in the test conditions. Wheel slip of 26.05-33.63 % and the field capacity of 0.17 - 0.20 ha/hr were observed during plowing operation. Further tractive performance tests using a three-point linkage configuration are recommended in Thailand field conditions. Different designs of cage wheels are recommended to be tested to optimize the tractive performance.

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Performance analysis of a 746 W HTS generator equipped with 70 A class contactless superconducting field exciter

  • Chae, Yoon Seok;Kim, Ho Min
    • Progress in Superconductivity and Cryogenics
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    • v.22 no.3
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    • pp.1-6
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    • 2020
  • This paper presents the analysis results on the electrical output performance characteristics of a 746 W high temperature superconducting generator (HTSG). The HTS field winding is charged by non-contact excitation method, i.e., contactless superconducting field exciter (CSFE) which is originated by rotary flux pump based on permanent magnet. In this paper, the preliminary current charging test was carried out using a 70 A CSFE to evaluate the performance of field exciter and analyze its non-contact excitation characteristics for the full-scale HTS field winding of the 746 W HTSG. First, the various contactless current-charging tests were conducted using assembly with HTS field winding and CSFE. Then, in order to estimate the output power performance characteristics of the 746 W HTSG, finite element analysis was conducted based on field excitation information which is experimentally measured under various operating conditions. Finally, the electrical output characteristics in no-load and load models were simulated by two-dimensional transient solver in ANSYS electromagnetics 19.0 release.

Influence of Organizational Culture on Performance of Building Construction Project (건축현장 조직문화가 프로젝트 성과에 미치는 영향)

  • An, Sung-Hoon;Bitamba, Bauma Frigeant
    • Journal of the Korea Institute of Building Construction
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    • v.15 no.5
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    • pp.501-506
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    • 2015
  • Construction companies want to improve the abilities of field organizations for improving the performance of construction projects. It is possible to improve the performance of construction projects by managing the field organizational culture, due to the field organizational culture is concerned with the abilities of construction field organizations. Therefore, the purpose of this study is to reveal the influence of the field organizational culture on the performance of building construction projects. The results of this study showed that field organizational cultural characteristics influence on the performance of construction projects. Best performed projects have the higher characteristics of a consensus culture and rational culture, and worst performed projects have the lower characteristics of a development culture and consensus culture. In addition, the characteristics of rational culture and hierarchy culture effect on the performance in worst performed projects. This study is expected to help to improve the performance management system in construction field organization.

The Effect of Adaptation Education on Performance Confidence and Practical Skill of Dental Hygiene Students before Field Practice (현장실습 전 현장적응교육이 치위생과 재학생의 수행자신감과 실무능력에 미치는 효과)

  • Kim, Myung-Eun;Kim, Hee-Kyoung
    • The Journal of the Korea Contents Association
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    • v.22 no.1
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    • pp.620-628
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    • 2022
  • The purpose of this study is to confirm the degree of improvement in performance confidence and executive ability after conducting field adaptation education to dental hygiene students who start their first field practice. Thirty dental hygiene students were evaluated with performance confidence, indirect and direct evaluation of practical skill before and after the field adaptation education was conducted for 15 hours. Also field practice satisfaction was investigated after field practice. A paired t-test was conducted to compare performance confidence, indirect executive ability, and direct practical ability before and after education. Pearson's correlation was performed on the correlation between field adaptation education and field practice satisfaction. Linear regression analysis was performed to identify the influencing factors of field practice satisfaction. As a results, performance confidence, indirect and direct practical skills of after field adaptation program were increased than before that(p<0.05). The correlation between field adaptation education and field practice satisfaction showed that "education satisfaction" among the field adaptation education sub-regions correlated with "education content" and "support of field practice" among the field practice satisfaction sub-regions(p<0.05). Therefore, it is necessary to develop and management various adaptation education in the future as it increases the adaptability of the first field practice and increases the satisfaction of field practice.

Students' Field-dependency and Their Mathematical Performance based on Bloom's Cognitive Levels

  • Alamolhodaei, Hassan;Hedayat Panah, Ahmad;Radmehr, Farzad
    • Research in Mathematical Education
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    • v.15 no.4
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    • pp.373-386
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    • 2011
  • Students approach mathematical problem solving in fundamentally different ways, particularly problems requiring conceptual understanding and complicated strategies. The main objective of this study is to compare students' performance with different thinking styles (Field-dependent vs. Field independent) in mathematical problem solving. A sample of 242 high school males and females (17-18 years old) were tested based on the Witkin's cognitive style (Group Embedded Figure Test) and by a math exam designed in accordance with Bloom's Taxonomy of cognitive level. The results obtained indicated that the effect of field dependency on student's mathematical performance was significant. Moreover, field-independent (FI) students showed more effective performance than field-dependent (FD) ones in math tasks. Male students with FI styles achieved higher results compared to female students with FD cognitive style. Moreover, FI students experienced few difficulties than FD students in Bloom's Cognitive Levels. The implications of these results emphasize that cognitive predictor variables (FI vs. FD) could be challenging and rather distinctive factor for students' achievement.

Field test of high-performance concrete (고성능 콘크리트 현장 시험시공)

  • 신동수;노재호;박연동;권영호;한정호;조일호;백명종
    • Proceedings of the Korea Concrete Institute Conference
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    • 1995.04a
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    • pp.171-176
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    • 1995
  • In recent years, Hith Performance Concrete has attracted world wide attention for its workability, strength and long-term durability. A field test was conducted to confirm the properties of high performance Concrete in situconditions. This paper describes the concrete materials, mix proportions, fresh state properties, some aspects of placability and qualty control results for field test. From the result, it was found that it is possible to produce High Performance Concrete with self-compactable and high strength.

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