이차함수에서 두 변량사이의 관계 인식 및 표현의 발달 과정 분석: 민선의 경우를 중심으로

이동근 ( Dong Gun Lee ),문민정 ( Min Joung Moon ),신재홍 ( Jaehong Shin ) 한국수학교육학회 2015 수학교육 Vol.54 No.4

The aim of this qualitative case study is twofold: 1) to analyze how an eleventh-grader, Min-Seon, conceive and represent a pattern of change between two varying quantities in a quadratic functional situation, and 2) further to help her form a concept of ``derivative`` as a tool to express the relationship with employing a concept of ``rate of change.`` The result indicates that Min-Seon was able to construct graphs of piecewise functions that take average rates of change as range of the functions, and managed to conjecture the derivative of a quadratic function, y=x ^{2}. In conclusion, we argue that covariational approach could not only facilitate students`` construction of an initial function concept, but also support their understanding of the concept of ``derivative.``

유리섬유강화 복합절연재료의 열화특성에 관한 연구

이규철,유근민,김경석,박홍태 울산대학교 1996 공학연구논문집 Vol.27 No.2

본 연구에서는 주위 환경 열화에 따른 복합절연재료의 절연특성과 수명을 향상시키기 위해 고온에서 흡습량을 변화시켰을 때와 탈습량을 변화시켰을 때 흡십시료와 탈습시료의 전기적 특성 및 기계적 특성을 조사하였다. 유리섬유 각층의 흡습상수는 각각 1층에서 0.0117, 2층에서 0.0123, 3층에서 0.0152를 나타냈다. 전기적 특성 및 기계적 특성은 복합재료의 흡습에 따라 크게 떨어졌다. 70℃에서 습기가 완전히 건조되어도 흡습전의 전기적 및 기계적 특성을 얻기가 어려운 것으로 나타났다. 수분에 의해 발생한 복합절연재료내에 존재하는 많은 결함들은 에폭시 메트릭스와 필라사이에 존재하였다. The electrical and mechanical properties of moisture absorbed and moisture desorbed specimens were investigated to improve the insulating characteristics and the reliability of composite materials against environment aging. Moisture absorption constants with the layers of glass fiber showed 0.0117 in 1 layer, 0,0123 in 2 layer and 0.0152 in 3 layer, respectively. Although moisture was removed at 70℃, it was impossible to obtain the initial electrical and mechanical properties. Many defects induced by moisture were observed at the interface between epoxy matrix and filler in composite materials.

충남 서북부지역 여성의 질세포진 검사에 대한 임상적 고찰

이석민,선우재근,장경택,서수형,김민관,배동한 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.2

Pap smear were performed to 30,294 women living in the north-west of Chung-nam. The result are summarized below 1. Positive vaginal cytology was 1.09 percent. 2. 72 percents women in their 30's and 40's experienced vaginal cytology. 3. Vaginal cytology was performed at a decreasing rate as age increases. 4. Positive cytology rate is 2.42% higher than average for elderly women over the age of 65. The present date indicates that pap smear is being widely recognized to be important but they needs to be continued advocacy for pap smear.

마쇄처리 고추의 냉동저장중 이화학적 성분의 변화

설민숙,황성연,이현자,박소희,김종군 한국식생활문화학회 2004 韓國食生活文化學會誌 Vol.19 No.2

To investigate physico-chemical changes of mashed red repper and red pepper powder during frozen storage, we analyzed the quality of samples after mashing, mashing and blanching, mashing and addition of vitamin C, mashing and addition of NaCl. The most important quality factor of red pepper is red color. α value of red pepper powder of Pochungchun was 31.51. These results showed that those processing methods were effective to preserve red color. Capsanthiin contents of mashed red pepper treated with vitamii C were decreased 1.8% after 180 days of frozen storage. Thii decrease was the Least, showing that addition of vitamin C helped retaining capsanthiin contents. Capsaicin and dihydrocapsaicin contents in Pochungchun powder were decreased 11.9 and 18.3% during frozen storage respectively. These results showed that capsaicin was more stable than dhycrocapsaicin during frozen storage. Generally capsaicin and dhycrocapsaicinin the Pochungchun red pepper frozen-stored after mashing were less decreased than red pepper powder, and addition of vitamin C to the mashed red pepper was the most effective to retain capsaicin and dihydrocapsaicin than others. The content of vitamin C in the red pepper frozen-stored after mashing and blanching was 12.0 mg/100g, compared with 44.0mg/100g in the sample stored after only mashing. This suggested that blanching process destroyed vitamin C in the mashed red pepper. Addition of salt in the mashed red pepper showed the same inclination. But, addition of vitamin C to the mashed red pepper was decreased 32.9%, compared with 69.0% in the mashed red repper during frozen storage. Theser results indicated that addition of vitamin C could retain vitamin C in the mashed red repper.

태권도 지도자들이 체육관 경영 시 고려하는 주요 요인 분석

조광민,이건희,김상유 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.3

Taekwondo which has adopted as a formula competitive games in 2004 Athens Olympic is establishing itself as world-widely recognized marshal arts, Taekwondo training centers which perform most of Taekwondo education, however, have been giving rise to many problems, Among others, reduction of the number of training peoples and limited an age group are the most serious ones. The purpose of this study was to help the Taekwondo trainers with solving various problems, such as facilities, trainer's quality, and training programs, and with consequently managing successful training center. It was abstracted by cluster random sampling method from Taekwondo Masters who work or operate Taekwondo Gym A questionnaire was sent to a Taekwondo Masters, Out of 300 copies, 196 copies were actually used in the practical analysis, Any copies with lost pages or insincere answers were excluded. For this study, SPSS 11.0 for Windows statistic package were used to analyzing collected samples, To analyze the data, frequency analysis, multiple responses, t-test, factor analysis, One-way ANOVA were conducted. And Scheffe method was used for the post analysis, investigating the propriety of the questionnaire, the factors analysis was executes by varimax after the professionals' review about the selecting Taekwondo Gym. As the result of the factor analysis, Factor 1 was named as the master's talent, Factor 2. as the accessive to the Taekwondo Gym and Factor 3 as the facility of Taekwondo Gym, And internal, external of Master, In the questionnaire of this study, reliability was used to verifying All Cronbach's a were over .700. As a conclusion, a diet program or a physical-training program need be developed forvarious groups of customers from the youth to the old, and training programs and in future study, marketing strategy for regional. needs should also be made.

저사이클 피로수명에 영향을 미치는 구상흑연주철의 흑연입자수의 영향

김민건,이병현,유병호 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.B

Low cycle fatigue life of spheroidal graphite cast iron is determined by the morphological parameters of internal graphite. The aim of this study is to clarify the effect of the number of nodular grain of spheroidal graphite cast iron on low cycle fatigue life. Two specimens that have identical average nodular grain size by changing nodular grain volume fraction and different number of nodular grain count was tested. In this paper, the parameter governing fatigue life through fatigue test, the number of nodular grain seriously affect fatigue life and nodular grain size is no longer governing parameter of it.

SNCM강의 피로균열의 발생 및 전파속도에 미치는 질화처리의 영향

김민건,이상호 강원대학교 산업기술연구소 2003 産業技術硏究 Vol.23 No.A

Effect of nitriding on fatigue crack imtiation and growth rate has been studied on SNCM. Specunens were nitnded for 15 hr at 860℃. The fatigue limit of nitrided specunens was superior to that of annealed(860℃. 15 hr) specimens. Based on detailed observations of slip band and micro crack initiation, it is concluded that the excellent fatigue limit of nitrided specunens is attnbuted to improved slip initiation resistance by nitriding The charactenstic of fatigue crack growth rate of nitrided specimens was investigated and compared with those of annealed specunens It was found that by nitriding the crack growth rate was markedly decreased and the threshold stress intensity factor range was improved. It is concluded that the excellent fatigue limit of nitnded specunens is also attributed to unproved fatigue crack growth rate and threshold stress intensity factor range by nitriding

2단 평행구조 로보트 프로그램 개발

박근우,이민기 國立 昌原大學校 産業技術硏究所 1996 産技硏論文集 Vol.10 No.-

This paper introduces the development of program for the double parallel robot which is applied to a machining work. The robot system consists of a robot, PC (personal computer), DMC (DSP Motion Controller), and machining tools. We analyze the motions of robot by an inverse kinematics +and drive the motions by DC Servo motors. In order to actuate the motor, we use the motion functions of the DMC, which is implemented in "C" language. Without adding a teaching box, we teach the robot with keyboard itself. Furthermore, we develope a 3-D graphics simulator to investigate the feasibility for application program in off-line.

젤라틴 제조시 추출온도가 젤라틴의 물리적 특성에 미치는 효과

염건웅,이미연,민상기,이성,이혜정 건국대학교 동물자원연구센터 2000 動物資源硏究誌 Vol.21 No.-

본 실험에서는 돈피를 원료로 acetic acid에 산침한 후, 열수 온도를 달리하여 추출해 낸 젤라틴의 점도, 겔강도, 색도 등의 물리적인 성질을 비교하였다. 산침 후 무게는 원료무게의 2배 이상 증가하였으며 팽윤율은 평균 115.9%로 증가하였고, 산침 후 두께는 평균 2.02mm, 두께의 팽윤율은 152.6%로 증가하였다. 추출율은 온도에 따라서 60℃<100℃<80℃<121℃ 순으로 나타났으며 추출온도별로 비교하면 동일한 온도, 동일한 전단속도에서 점도는 121℃<100℃<60℃<80℃ 순으로 높게 나타나 고온에서 추출하였을 경우 점도가 낮아짐을 알 수 있었다. L-value는 100℃에서 74.78로 가장 높게 나타났으며 121℃에서 가장 낮은 51.96을 보여주었다. a-value는 80℃에서 -1.35로 가장 낮은 값을 나타내었으나 60℃, 100℃, 121℃에서는 유의차가 없었다. b-value는 100℃에서 6.46으로 가장 높게 나타났으며, 80℃에서 3.78으로 가장 낮은 값을 나타내었으나 60℃와 121℃간에는 유의성이 발견되지 않았다. Gel 강도측정 결과를 보면 견고성(hardness)은 121℃<100℃<60℃<80℃순으로 크게 나타났으며, 응집력(cohesiveness)은 추출 온도별로 유의성을 나타내지 않았고 평균 0.66을 나타내었다. 탄성력(elasticity)역시 평균 0.977g/cm²로 추출온도별 유의성은 나타나지 않았다. 부서짐성(brittleness)은 견고성과 마찬가지로 121℃<100℃<60℃<80℃순으로 80℃가 가장 높았다. 그리고 부착성(adhesivenss)의 경우 추출온도별 유의성은 100℃와 121℃에서는 나타나지 않았고, 60℃와 80℃에서만 나타났다. 따라서 추출온도가 낮을수록 견고성과 부착성이 높은 것으로 나타났다. The physical properties of gelatin extracted from pork skin were investigated by determmation of expanding rate of skin, viscosity, gel strength and color depending on extraction temperature. Pork skin during acid treatment was expanded to about 152.6%. The extract rate was increased by 60℃<100℃<80℃<121℃. Viscosity of extracted gelatin sol was increased by 121℃<100℃<60℃<80℃. L-value was highest at 100℃(74.78) and lowest at 121℃(51.96). a-value was lowest at 80℃(-1.35), but there were no significant difference between temperatures of 60, 100 and 121℃. b-value was highest at 100℃(6.46) and lowest at 80℃(3.78). Hardness of gel was increased by 121℃<100℃<60℃<80℃ and cohesiveness was about 0.66 whereas elasticity was about 0.977g/cm³, Brittleness was increased by 121℃<100℃<60℃<80℃, and it was highest at 80℃, which showed similar trend with hardness. Adhesives were no significance difference between 100 and 121℃. From these results, it was achieved that gelatin becomes hard and adhesive when the extraction temperature is low.

기지국 최적화를 위한 전역 탐색 알고리즘의 성능 해석

오정근,박미선,이성신,이민혁,변건식 동아대학교 정보기술연구소 2002 情報技術硏究所論文誌 Vol.10 No.1

In the design of mobile wireless communication system, Base station location is one of the most important parameters. Designing base station location, the cost of equipment makes low by combining various, complex parameters. We can solve this problem by combining optimization algorithm, such as Simulated Annealing, Tabu Search, Genetic Algorithm, Random Walk Algorithm that have been used extensively for global optimization. This paper shows the 4 kinds of algorithm to be applied to the base station location optimization of mobile communication system and then compares, analyzes the results and shows optimization process of algorithm.