• Title/Summary/Keyword: PRE

Search Result 24,281, Processing Time 0.039 seconds

Fuzzy r-Pre-semineighborhoods and Fuzzy r-Pre-semicontinuous Maps

  • Lee, Seok-Jong;Eoum, Youn-Suk
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.1 no.1
    • /
    • pp.62-68
    • /
    • 2001
  • In this paper, we introduce the concepts of fuzzy r-pre-semiopen and r-pre-semiclosed sets. With them we define fuzzy r-pre-semiinterior and r-pre-semiclosure. We also introduce and investigate the properties of a fuzzy r-pre-semicontinuous map, a fuzzy r-pre-semiopen map and a fuzzy r-pre-semiclosed map. These concepts are generalizations of the Bai Shi-Zhongs fuzzy pre-semicontinuity.

  • PDF

Effects of Pre-learning Attitude on Academic Achievement in the Flipped Learning Methodology (A Case of Applied Thermodynamics) (플립러닝 교수법에서 사전학습태도가 학업성취도에 미치는 영향 (응용열역학 교과목 적용 사례))

  • Ryu, Kyunghyun
    • Journal of Engineering Education Research
    • /
    • v.26 no.6
    • /
    • pp.51-61
    • /
    • 2023
  • In this study, the effects of pre-learning attitude on learning participation and academic achievement was analyzed when applying the flipped learning methodology to engineering subject education. The modified PARTN teaching and learning model was applied, and pre-class survey, assessment on learning in pre-class, and post-class survey were conducted to analyze the effectiveness of flipped learning. The results were analyzed for 24 students who took the applied thermodynamics lecture. They were asked to take the course with the videos provided in the pre-class stage, and a pre-learning assessment was conducted to measure the completeness and understanding of the learning. As a result of the study, it was found that students with relatively excellent learning ability had excellent pre-learning evaluation results and excellent final academic achievement. In addition, the lower the pre-learning completion rate within the pre-learning period or the higher the learning rate using mobile devices, the more difficult it was to faithfully complete pre-learning, leading to poor pre-learning evaluation results. Meanwhile, the survey revealed that conducting pre-learning assessments were helpful in encouraging individual learning. In addition, cases reflecting pre-learning evaluation results to course grades showed higher pre-learning evaluation results than cases not reflecting pre-learning evaluation results to course grades, and in flipped learning classes, pre-learning evaluations act as a factor that promotes pre-class learning.

L-pre-separation axioms in (2, L)-topologies based on complete residuated lattice-valued logic

  • Zeyada, Fathei M.;Abd-Allahand, M. Azab;Mousa, A.K.
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.9 no.2
    • /
    • pp.115-127
    • /
    • 2009
  • In the present paper we introduce and study L-pre-$T_0$-, L-pre-$T_1$-, L-pre-$T_2$ (L-pre-Hausdorff)-, L-pre-$T_3$ (L-pre-regularity)-, L-pre-$T_4$ (L-pre-normality)-, L-pre-strong-$T_3$-, L-pre-strong-$T_4$-, L-pre-$R_0$-, L-pre-$R_1$-separation axioms in (2, L)-topologies where L is a complete residuated lattice.Sometimes we need more conditions on L such as the completely distributive law or that the "$\bigwedge$" is distributive over arbitrary joins or the double negation law as we illustrate through this paper. As applications of our work the corresponding results(see[1,2]) are generalized and new consequences are obtained.

Fuzzy (r,s)-pre-semicontinuous mappings (퍼지 (r,s)-pre-semicontinuous 함수)

  • Lee, Seok-Jong;Kim, Jin-Tae;Eom, Yeon-Seok
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2007.11a
    • /
    • pp.191-194
    • /
    • 2007
  • In this paper, we introduce the concepts of fuzzy (r,s)-pre-semiopen sets and fuzzy (r,s)-pre-semicontinuous mappings on intuitionistic fuzzy topological spaces in ${\v{S}}ostak's$ sense. The concepts of fuzzy (r,s)-pre-semiinterior, fuzzy (r,s)-pre-semiclosure, fuzzy (r,s)-pre-semineighborhood, and fuzzy (r,s)-quasi-pre-semineighborhood are given, and several properties of these concepts are discussed. Using these concepts, the characterizations for the fuzzy (r,s)-pre-semicontinuous mappings are obtained. Also, we introduce the notions of fuzzy (r,s)-presemiopen and fuzzy (r,s)-pre-semiclosed mappings on intuitionistic fuzzy topologica spaces in ${\v{S}}ostak's$ sense, and then we investigate some of their characteristic properties.

  • PDF

Relationships Between Pre-Skidding and Pre-Braking Speed (활주 직전과 제동 직전 속도의 상관관계 규명에 관한 연구)

  • Ryu, Tae-Seon;Jeon, Jin-U;Park, Hong-Han;Lee, Su-Beom
    • Journal of Korean Society of Transportation
    • /
    • v.27 no.1
    • /
    • pp.43-51
    • /
    • 2009
  • This paper investigates the accuracy of vehicle pre-braking speed estimates based upon tire/roadway coefficient of friction (drag factor) measurements and skid mark measurements Data for pre-braking and pre-skidding speeds were collected to determine if there were any correlations between pre-braking speeds and pre-skidding speeds. Braking tests were performed on two vehicles using various measurement devices including a fifth wheel, a speed gun, and a vericom 2000. The vehicle speeds, braking distances, skid mark distances, and deceleration histories were recorded. From these data. coefficients of friction and vehicle pre-skidding speeds for the tested road surface were calculated. The pre-skidding speeds were then compared to the actual pre-braking speeds of the vehicles in order to establish relationships between pre-skidding and pre-braking speed. A correlation between the Pre-skidding speed and the actual pre-braking speed was established for the study data.

A FEASIBILITY STUDY ON THE NUMERICAL PRE-ASSEMBLY SIMULATION USING 3D LASER SCANNING MEASUREMENT

  • Kyoungmin Kim ;Seok Kim ;Chan-Hyuk Park ;Kyong Ju Kim
    • International conference on construction engineering and project management
    • /
    • 2005.10a
    • /
    • pp.1193-1198
    • /
    • 2005
  • The pre-assembly takes a large portion of the fabrication cost of steel bridges. In order to save the fabrication cost through the improvement of the conventional pre-assembling process, this research investigates a numerical pre-assembly simulation as an alternative to current pre-assembling process. The 3D laser scanning was utilized in site and measuring data for steel box were analyzed. The productivity of pre-assembly simulation system is compared with the conventional pre-assembling system. This paper identifies feasibility on the alternative pre-assembling process and then proposes the scheme of the pre-assembly simulation system development satisfying the current pre-assembly inspection of standards.

  • PDF

A Study for Resistance Spot Weldability of Pre-sealed Sheet Steel for Automobile Body by Using Pre-current (예비전류를 이용한 자동차용 프리실드 강판의 저항 점 용접성 향상에 관한 연구)

  • Park, Tae-Gyu;Yun, Sang-Man;Rhee, Se-Hun
    • Journal of Welding and Joining
    • /
    • v.27 no.6
    • /
    • pp.36-42
    • /
    • 2009
  • In the present day, new performances are demanded for automobile body steel sheet for example, light weight, durability, resistance corrosion and environmental protection. For an improvement of resistance corrosion, European automobile companies developed pre-sealed steel in 1990's. Pre-sealed steel have organic coated layer upper zinc coated layer. Evaluating a resistance spot weldability of pre-sealed steel plate is important because resistance spot welding is used mainly in automobile body joining process. In this study, evaluating a weldability of pre-sealed steel plate was carried out using lobe diagram, dynamic resistance and high-speed image. Usually, Pre-sealed steel has poor weldability than GA steel's. To improve a weldability of pre-sealed steel sheet, pre-current was applied to welding process. Pre-current is applied prior to base-current. In conclusion, the weldability of pre-sealed steel has been improved than GA steel's by applying pre-current.

Performance Variation of a Combined Cycle Power Plant by Coolant Pre-cooling and Fuel Pre-heating (냉각공기 예냉각과 연료예열에 의한 복합발전 시스템의 성능변화)

  • Kwon, Ik-Hwan;Kang, Do-Won;Kim, Tong-Seop;Kim, Jae-Hwan
    • The KSFM Journal of Fluid Machinery
    • /
    • v.15 no.3
    • /
    • pp.57-63
    • /
    • 2012
  • Effects of coolant pre-cooling and fuel pre-heating on the performance of a combined cycle using a F-class gas turbine were investigated. Coolant pre-cooling results in an increase of power output but a decrease in efficiency. Performance variation due to the fuel pre-heating depends on the location of the heat source for the pre-heating in the bottoming cycle (heat recovery steam generator). It was demonstrated that a careful selection of the heat source location would enhance efficiency with a minimal power penalty. The effect of combining the coolant pre-cooling and fuel pre-heating was also investigated. It was found that a favorable combination would yield power augmentation, while efficiency remains close to the reference value.

ON FUZZY FAINTLY PRE-CONTINUOUS FUNCTIONS

  • Chetty, G. Palani;Balasubramanian, G.
    • East Asian mathematical journal
    • /
    • v.24 no.4
    • /
    • pp.329-338
    • /
    • 2008
  • The aim of this paper is to introduce a new generalization of fuzzy faintly continuous functions called fuzzy faintly pre-continuous functions and also we have introduced and studied weakly fuzzy pre-continuous functions. Several characterizations of fuzzy faintly pre-continuous functions are given and some interesting properties of the above functions are discussed.

  • PDF