학습컨설팅을 위한 대학생 학습역량 진단도구 개발 사례: K대학 사례를 중심으로

송명현,이금호,강승찬 대학교육개발센터협의회 2023 대학 교수-학습 연구 Vol.16 No.2

The purpose of this study is to develop a learning competency diagnosis tool for learning consulting suitable for K University characteristics. In this study, the areas, components, and questions of learning competency were developed through a review of previous studies and expert advice, and a preliminary survey and main survey were conducted. The results can be summarized as follows. First, through the modeling of the learning competency of University K, the purpose and direction of the development of the learning competency diagnosis tool were clarified, and the definition, major domains, small domains, and component of the learning capability were derived. Second, as a result of exploratory factor analysis, 17 sub-factors were reduced to 16 sub-factors. And as a result of the confirmatory factor analysis, the fit of the model was found to be good, so the learning competency diagnosis tool was established as 3 areas, 6 competencies, 16 sub-competencies, and 104 items. Third, based on the results of the development of the learning competency diagnostic tool, a diagnosis manual including score calculation logic, descriptive statistical table, profile interpretation, was developed.

Wavelet 변환을 이용한 전동기 고장진단

송명현 順天大學校 1998 論文集 Vol.17 No.1

This study discusses the wavelet application for detecting moter faults using current signals. Diagnosis methods with current signals are very effective, inexpensive and simple methods. In this paper, several artificial faults; unbalance, broken rotor bars and some kinds of bearing faults, are made, and then electric motor currents are collected, processed and transformed that signals using wavelet for extracting proper features. The experimental results show that the effective detecting method can be obtained by using wavelet transform for current signals.

전류측정에 의한 AC서보모터의 언밸런스 고장검출

송명현,조병호,김부열 순천대학교 2000 순천대학교 자연과학논문집 Vol.19 No.1

Using current measurement, the analytic method for the unbalance fault detection of 3Φ induction servomotor was proposed. The fault detection of the load unbalance has been studied by means of the measure of vibration. In the conventional method, the additional vibration sensors are set up to measure the vibration properly, but the method introduced in this paper, a current sensor for motor control is used for measuring the load current, so there is no need for additional sensors. After measuring the current caused by unbalance load, the FFT spectrum of the measared current were analyzed and compared with the spectrum pattern of the balanced load. Varying the motor speed by 500, 1000, 1500 and 2000 rpm, some characteristic frequency for detecting the unbalance fault were found. These experimental results show that the proposed current measuring method is more simple, easy, and effective than the conventional vibration measuring method.

전류측정에 의한 전동기 고장 진단

송명현,김재현 순천대학교 공업기술연구소 1998 工業技術硏究所論文集 Vol.12 No.-

This paper discusses the diagnosis of motor for detecting the air gap eccentricity, broken rotor bars and outlace fault of bearing. For developing of the on-line monitoring system, a simple method of current spectral analysys is proposed. Though it is processed within a limited range of frequency for simplicity, but it can be obtained the possible detecting frequency for monitoring the some motor faults. The experimental results give the proper frequency and amplitude dB levels for detecting the motor faults.

브러시리스 직류전동기의 가변구조 위치제어기 설계

송명현 順天大學校 1989 論文集 Vol.8 No.1

본 연구에서는 이원전기 trapezoidal 형 브러시리스 직류전동기를 이용 위치제어기를 구성함에 있어서 모든 상태를 측정하지 않고서도 가변구조제어가 가능하며 채터링현상을 감소시킬 수 있는가에 대하여 고찰한 결과 컴퓨터 시뮬레이션을 통하여 다음의 결론을 얻었다. 1) 속도, 위치 정보에 속도미분항을 구하여, 전류를 측정하지 않고서도 전류정보를 이용한 경우와 동일한 특성을 얻을 수 있었다. 즉 감소차수 스위칭함수와 스위칭이 가능하다. 2) 고이득 ON-OFF패턴을 이용한 경우 발생된 채터링을 영역을 설정하여 현저히 감소시킬 수 있었다. 3) 전반적으로 강인한 제어기를 구성할 수 있었다. 본 연구에서, 컴퓨터 시뮬레이션을 통해, 얻은 결론을 현재 DSP를 이용한 ON-OFF패턴 발생기의 제어기에 적용중에 있으며 앞으로 고차계로의 확장 및 체계화가 필요하며 부하변동시 강인성 확보에 대해서도 연구가 필요하다. Variable Structure Control (VSC) theory has been applied to servo system because of its merit of insensitivity to the plant parameters variation and external disturbances. In order to abtain above merit, the VSC must have high switching frequency and full-order switching function should be composed with all of the state variables such as position, velocity and current. But current measuring causes the overall system to be complex and implementation cost to be increased. To overcome this problem, this paper discusses a reduced-order switching function with the use of only speed and position informations. Also chattering reduction of control input, which uses high gain ON-OFF pattern, is discussed. Computer simulations are executed to the position control of trapezoidal type BLDC motor. The results show the effectiveness of the reduced-order switching function and chattering reduction method.

온라인 프로젝트 기반학습(PBL) 적용 비교과 프로그램 개발 사례 연구

송명현,김미화 한국공학교육학회 2022 공학교육연구 Vol.25 No.6

This study aims to develop and implement extra-curricular program applying project-based learning (PBL) and to find out its effectiveness. The research was conducted from March 2021 to December 2021 according to the ADDIE model. Surveys, t-test and descriptive statistics were also conducted. The results of the study are as follows. First, project-based learning was applied to the extra-curricular program by reflecting the characteristics of students of University A and the requirements of the person in charge of the teaching and learning center. Second, project tasks related to education of universities were proposed. Third, the programs were designed as three common courses and four consulting courses. Fourth, the program was conducted with 32 students for two months. Fifth, the post-test results of problem-solving skills rose to 0.9 points compared to the pre-test but there was no significant difference, while the post-test resultsof communication skills were 0.5 points lower than before and statistically significant. Sixth, the satisfaction survey result was high with a rating of 4.59. Lastly, educational implications are also discussed.

CF-reduplication in English: Dynamic Prototypes & Contrastive Focus Effects

송명현,이정민 한국언어학회 2014 언어 Vol.39 No.4

CF-reduplications refer to three different levels of a category: the prototype of a category, the subcategories in a category or a category itself. The CF-marked modifier receives the intension of a base word and produces a contingently determined denotation of CF-reduplications, on the basis of dynamic prototypes in the minds of speakers. The Contrastive Focus exhaustively selects the denotation of the CF-reduplications out of immediately relevant alternatives given in the discourse with the exclusive implication that only the denotation of the reduplicated expression is intended by speakers. CF-reduplications semantically have dynamically changing denotations and pragmatically facilitate the communication between speakers with contrastive focus effects.

역량기반 대학생 또래교수(Peer tutor) 양성교육 지원체제 구축 : A대학 사례를 중심으로

송명현,김미화,Song, Myunghyun,Kim, Mi Hwa 한국콘텐츠학회 2022 한국콘텐츠학회논문지 Vol.22 No.10

This study aims to develop a training program to strengthen the competency of peer tutors at A University and to establish a sustainable system. It was conducted in the process of developing, operating, evaluating, modifying, and supplementing the curriculum for about two years from January 2019 to February 2022. In-depth interviews, surveys, literature reviews, and expert surveys were used as research methods. The research results can be summarized as follows. First, by combining in-depth interviews and ranking of educational needs of peer tutors' competencies, the researchers designed peer tutors training curriculum and certification system, and these were certified by conducting expert surveys. Second, from March 2020 to the end of February 2022, peer tutor training and certification system were operated, and as a result of a satisfaction survey of students, 4.33 points on average in 2020 and 4.61 points on average in 21, indicating high satisfaction. Finally, the implications were discussed for establishing peer tutor training programs and system in universities.

소형 브러시리스 직류 전동기의 토크 특성 향상에 관한 연구

송명현,김용일 순천대학교 공업기술연구소 1989 工業技術硏究所論文集 Vol.3 No.-

In this paper, we describe the optimal driving method and magnetic flux distribution of permanent magnet which enhance torque chracteristics in small―sized 3―phase brushless DC motors. The disadvantages of conventional 120° constant current drive method are torque ripple, switching noise and spike voltage due to the inductance of stator coil. This shortcommings can be avoided by the switching slew―rate of driving current which is called linear voltage driving method. The aim of this study is to analyze linear voltage driving method quantatively and to determine optimal drive current waveform through computer simulation. The selection of commutation angle and slew rate of a new driving current at switching instants makes torque ripple index minimize and average torque maximize. Considering two dimensional nonlinear magnetic flux distribution on the permanent magnet, we suggest optimal flux distribution according to the presented driving method which improves torque characteristics.

얼굴요소 탐지와 Correlation 기법에 의한 얼굴 인식

최남섭,김경민,이세영,박중조,송명현 여수대학교 1998 論文集 Vol.13 No.2

Automatic face recognition methods are based on the computation of similarity of face images which are represented as geometrical feature vectors or template models. In this paper, we developed a face recognition algorithm by using correlation technique with templates of face elements(eyes, nose, mouth). Our method of face recognition is mainly divided into two stages. In the first stage, the locations of each face element are detected. This process is for reducing the computational time in correlation process. In the second stage, input unknown image is correlated on the detected area with corresponding template, in which normalized correlation technique is used for reducing illumination effect in the image and templates. And matching scores are compared to obtain face recognition result. The experimental result shows the recognition rate of 95.75% for 225 testing images of 45 persons.