Y-△ 기동 LSPM의 회전자 자극 형상 설계에 관한 연구

송지효 동아대학교 대학원 2018 국내석사

자란만에서의 유해성 와편모조류 Cochlodinium polykrikoides 발생과 환경특성

송지효 부경대학교 대학원 2012 국내석사

The dinoflagellate Cochlodinium polykrikoides is an ichthyotoxic species of harmful algae. Its outbreak had been known to be caused by inflows from outside. However, a recent identification of its resting cysts suggested a possibility of its potential for internal outbreak. Therefore, rapid and precise methods of identifying resting cysts and researches on regional resting cyst potential were required. Thus, the possibility of seed bed of C. polykrikoides was confirmed from the results of previous studies, and the occurrence of Nematodinium sp. that had a similar biological trend on initial germination processes was investigated. And growth-promoting ecological factors on harmful algal blooms were measured from probable seed beds. Around Jaran Bay during the study period, water temperature was 16.88∼29.52℃, salinity was 20.35∼34.79 psu and dissolved oxygen was 4.00∼9.63 ㎎/L at the surface. An initial development of C. polykrikoides was observed at all stations surveyed in 2010 and 2011. During that period, water temperature was 19∼21℃, salinity was 34.11∼34.23 psu and dissolved oxygen was 7.34∼7.37 ㎎/L at the surface. The prevalence of C. polykrikoides motile cells tended to be significantly affected by ecological factors such as water temperature, DO and salinity. Among them, water temperature affected the initial development of C. polykrikoides significantly. And after DO decreased, motile cells of C. polykrikoides tended to increase. A decrease in salinity due to rainfall resulted in a decrease in motile cells of C. polykrikoides. As the results of physical changes, the development of C. polykrikoides did not proceed to bloom scales. Cyst germinants of C. polykrikoides and Nematodinium sp. appeared to show a similar tendency, and those of C. polykrikoides were detected two or three days after the first inoculum of those Nematodinium sp. As Nematodinium sp. and C. polykrikoides occurred on the spot almost at the same time, showing a tendency of occurrence similar to each other, they could be considered to play a role of an indicator species of initial development to each other, and they could be used in monitoring the initial development of C. polykrikoides in some specific sea areas. 유해적조생물 Cochlodinium polykrikoides는 1995년 764억으로 추산되는 막대한 수산피해를 발생시킨 이래로 매년 여름철에 남해를 중심으로 광역적으로 발생하여 지속적인 피해를 가져왔다. 그리하여 C. polykrikoides 적조에 대한 많은 선행연구가 이루어졌으며, C. polykrikoides 적조의 최초 발생·확산 원인으로 외부유입가설이 제시되었지만 한 가지 가설만으로는 쉽게 설명되지 않는 C. polykrikoides 적조의 발생과 확산에 대해 C. polykrikoides의 생활주기 중 유성생식에 의해 형성되는 내구성 휴면포자의 영향이 제시되었다. 그리하여 C. polykrikoides의 Seed population 조사를 통해 C. polykrikoides의 적조 잠재성을 조사하여 적조 생물 발생의 가능성이 추측되는 seed bed를 유추하였으며 그 seed bed의 유효함을 확인하였다. 그리고 휴면포자로서 유사한 물리적 동향과 초기 발생의 시기적 유사성을 지닌 Nematodinium sp.의 발생을 조사하였다. 그리고 발생 전후의 환경조건을 조사하여 C. polykrikoides의 적조 발생 특성을 알아보고자 하였다. 자란만에서 2010년 5월부터 7월 까지, 2011년 5월부터 7월 까지 C. polykrikoides 영양세포의 출현량, 수온, 염분과 용존산소를 조사한 결과, 조사기간 중 수온 최저 16.88℃에서 최고 29.52℃의 변화를 보였고, 염분은 20.35 ~ 34.79 psu, DO는 4.00 ~ 9.63 mg/L의 변화를 보였다. 수온 19~21℃, 염분 34.11~34.23 psu, 용존산소 7.34~7.37 mg/L이었을 때 각 정점에서 C. polykrikoides의 초기발생이 관찰되었다. 조사기간 동안 해역에서 C. polykrikoides 영양세포는 관찰되었지만 C. polykrikoides에 의한 대규모 적조발생은 관찰되지 않았으며 Nematodinium sp.의 관찰에서 두 종간의 최초 출현시기와 출현정점, 세포 증감 패턴에서 유사성을 발견하여 C. polykrikoides 발생의 지표종 역할을 할 수 있을 가능성이 기대되었다. C. polykrikoides의 출현양상은 수온과 용존산소, 염분 등 물리적 환경요인의 영향을 크게 받는 경향을 보여주었는데 각각 수온의 경우 C. polykrikoides의 초기발생 시기에 영향을 주는 것으로 판단되었고, 용존산소의 감소 이후 C. polykrikoides 영양세포의 증가가 일어나는 경향을 보여주었으며 강우에 의한 염분의 감소는 C. polykrikoides 영양세포의 감소를 가져오는 결과를 보여주었다. C. polykrikoides의 출현양상은 질소나 인, 규소 등의 영양염류의 변동과는 특별한 관계를 찾을 수 없었다.

학교 음악교육이 성인생활에 미치는 영향

송지효 숙명여자대학교 교육대학원 1987 국내석사

音樂은 人間의 發展過程에서 情緖面에 크게 寄與함은 물론 文化生活의 척도를 높이고 나아가서 人格을 形成하며 보다 훌륭한 品性을 지니게 하는 데 絶對的인 역할을 함은 周知의 事實이다. 오늘날의 敎育이 民主市民으로서의 資質과 能力을 開發하는, 즉 全人的 敎育이라고 定義할 때 音樂은 單純히 情緖와 感情의 能力에서 머무는 것이 아니고 보다 넓은, 다시 말하면 包括的 意味의 敎育的인 意義를 지니고 있음을 이해하여야 할 것이다. 音樂 敎育의 方法도 過去와는 달리 音樂을 唱歌로만 생각하지 않고 歌唱, 器樂, 創作, 感賞을 고루 포함한다. 指導의 槪念도 敎師 中心에서 學生 中心으로 옮겨져 被敎育者들의 審美的인 心性을 중요시하고 音樂의 깊은 世界를 體驗하며 生活化시키는 데 있다. 學校 音樂敎育이 成人들의 生活에 어떤 影響을 미치고 있는지 成人들의 音樂的인 實態를 把握하여 올바른 音樂 敎育의 方向을 提示하는 데에 多少나마 寄與 하고자 하며 音樂을 通하여 來日의 健全하고 밝고 맑은 豊饒로운 生活을 이끌어 나가려는 데에 本 硏究의 目的과 意義를 두는 것이다. 따라서 本 硏究에서는 學校 音樂敎育이 成人生活에 미치는 影響을 37個의 質問을 475名의 成人을 通해서 알아보았다. 이 結果 1. 學校 音樂敎育에서 音樂을 指導할때 音樂의 모든 領域을 고루 指導하여 音樂의 生活化에 不足함이 없도록 하여야 하겠다. 2. 學校 音樂敎育에서 좋은 音樂을 많이 듣도록 함으로서 더욱 情緖가 豊富한 調和된 人格을 形成하게 이끌어 나가야 되겠다. 3. 좀 더 많은 우리 歌曲을 指導하여 밝고 맑은 健全한 社會建設에 힘써야 되겠다. 4. 모든 指導層에 있는 사람들이 어떤 곳에서나 上下를 莫論하고 우리 生活속에 파고들어 健全한 音樂을 指導하고 즐기고 普及함으로서 情緖를 啓發하고 明朗하며 忠實하고 豊饒로운 社會建設을 이룩해야 되겠다. 끝으로 순수 音樂人들의 奉仕的 積極的인 社會參與가 무엇보다 要請되며 政府의 敎育的 歌曲 育成에 더 많은 政策的 支援을 바라는 바이다. The general contribution of music is found in improving the level of cultural maturity as well as in men's emotional development. From a view of historical perspective, the art of music has in fact played an absolute role in the cultivation of better character and personality. Apart from the illiberal definition that to teach is to develop a man, there is no education now against the principle of whole-minded teaching which aims at making a good advance in the gifts and abilities enough to be a democrat. Thus, the practice of music education takes in a broad sense much more than repetitive learning of feeling or emotional capacity. Contrary to the past in that most people regarded the whole of music as a simple collection of songs, today's method of music education makes no discrimination between singing, writing, appreciation and instruments, at all. The concept of guidance is also thought to be an intention that lays emphasis on students, not on teachers. All of music is firmly rooted in the students' everyday life who have learned it; they, indeed, experience themselves in the warmth of 'true' music and find many of aesthetic senses one by one. This study attempts to know the current state of how the school music education influences on the adult's life. Therefore the purpose of the study is to suggest some desirable directions of music education and to contribute to coming of much brightness and richness in their future life. 475 copies of questionnaire, included 37 questions in each of them, were sent to the same number of adults. Conclusions obtained from the statistical results are: I. An impartial guidance with no absence of any less-weighed area should be given in school music education, so that the realities of music might be all embodied in men's life. II. More opportunities of listening to good pieces must be provided in schools to set up better personality full of emotional accords than till now. III. The increase of the number of Korean lieds is needed in the education so as to have a sound and bright society. IV. Everybody of the upper class, under the creed of building up the public society of richer emotion, should make a great effort, with no limitation of the place or status, for the guidance and propagation of sound pieces in everyday life. V. Finally, more active and faithful social role-creation of the group of music lovers is needed above all, in parallel with policy support of the government.

성인 태권도 활성화 방안 모색과 마케팅 전략에 관한 연구

송지효 수원대학교 교육대학원 2008 국내석사

Follow the conclusion, three research questions about the plans of revitalization on the Taekwondo academies and marketing strategy would be suggested with several points. ▣ Research question 1 : What is the difference of the marketing factor and willingness to continue to be trained by the character of population statistics of taekwondo participants. 1) The difference of willingness to continue to be trained by population statistics : The difference of willingness to continue by gender distinction is meaningful in 5%; "I will drop-out in private Taekwondo academy." There is a difference in gender distinction. The factor of drop-out in private Taekwondo academy is meaningful in both gender distinction and education level. The difference of willingness to continue by income level is meaningful to the terms; "I want to train in private Taekwondo academy, even though I am dissatisfied with academy", "I will drop-out in private Taekwondo academy." The difference of willingness to continue related to the B variable is meaningful in 1 percent. 2) The difference of marketing factor by demographic characteristic : The marketing factor related to the gender distinction is meaningful in the terms of H(It is helpful to physical training and bodily development) and O(Dues of Taekwondo academy is expensive). The variable of H is meaningful in 5% and the variable of O is meaningful in 10%. The difference of marketing factor by age is meaningful in the terms of H(It is helpful to physical training and bodily development), K(The scale of Taekwondo academy is huge), M(I am easy to reach in Taekwondo academy),N(Dues of Taekwondo academy is expensive),and O(Dues of Taekwondo academy is expensive). They are meaningful in each 10%, 5%, 5%, 5%, and 5%. The most of marketing factor by education level is not meaningful in contrast of gender distinction and age. It is meaningful the variable of F(The training of Taekwondo is useful to reduce stress) in 10%. It means that there is a difference between F variable. Most of variables related to the income level is not meaningful. The term of P(The match rule and training method is well-known) is meaningful in 5% level. It means that there is a distinction between P variable by income level. ▣ Research question 2 : How does the degree of training affect to both willingness to training and marketing factor? 1) The effects of willingness to continue to be trained : the degree of training has positive effects on the willingness to continue to be trained. The result is meaningful in 1% level. Because the coefficient sign is plus, the willingness to continue to be trained is to strengthen by frequent of training. Also, the period of training has positive effects on the willingness to continue to be trained. It means that the person who has trained for a long time has strong willingness to continue to be trained. It is meaningful in 5% level. The results of multiple regression analysis, however, show that the frequency of training is meaningful to the willingness to drop-out the academy. Because the coefficient sign is negative, the frequency of training is to weaken by the willingness to drop-out the academy. It is meaningful in 1% level. But the period of training is not meaningful in 10% level. 2) The effects of the marketing factor : First of all, this study researches the effects of degree of training on the products in marketing factors. The period of training is meaningful in 1% level. Because the coefficient sign is plus, the period of training is to strengthen the positive thought to the Taekwondo. The effects of price show the meaningful results on the frequency of training contrast to the products. The high frequency of training person think that the price of training is expensive. This variable is meaningful in 1% level. The results of multiple regression analysis on the facilities is not meaningful in 10% level between two variables. Finally, two variables is meaningful in the view of promotion. Frequency of training is negative relation with promotion. It is meaningful in 1% level. Also, the promotion is positive relation with the period of training. It is meaningful in 5% level. ▣ Research question 3 : How does the marketing factors affect to the willingness to continue to be trained? Above all, this study researches the effects of frequency of training on marketing factor. According to the results of linear regression analysis, all variables except for promotion in the marketing factors show meaningful results. The more people think about the Taekwondo positively, the more people increase the frequency of participation. It is meaningful in 1% level. The more people think that it is expensive, the more people participate repeatedly. This variable is meaningful in 1% level. Finally, the facility is negative relation with the frequency of participation. It reveals meaningful results in 5% level. According to the result in the effects of marketing factor on the period, the products, price, and facility factor have meaningful result on the period of training. In the concrete review, the product is negative relation with the period of training, the price is negative relation with the period of training, and the facility is positive relation with the period of training. Each variable shows meaningful result in 1%, 10%, and 1%. level.

A methodology for predicting the phase fraction and microhardness of welded joints using heat transfer analysis and integrated modeling

송지효 서울대학교 대학원 2024 국내박사

Repeated heating and cooling during welding results in diverse microstructures and mechanical properties, which makes experimental analysis difficult. This study presents a methodology for predicting the phase transformation and fraction and microhardness at every location of welded joints. The methodology consists of the following steps: construction of an austenite decomposition database (AD data), heat transfer analysis, prediction of essential parameters, and prediction of the phase fraction. The AD data encompassed a comprehensive range of prior austenite grain size (PAGS) and t8/5 (cooling time between 800 and 500°C) values. The heat transfer model was developed to simulate the heat transfer during welding, obtain the thermal cycles, and calculate the critical parameters (austenite fraction, PAGS, and t8/5). Finally, the phase fraction was predicted by combining the AD data and parameters and the microhardness was calculated by considering microhardness value of each phase. This methodology, initially developed for single pass welding, has been successfully extended to multi pass welding. The developed methodology was refined to consider the effects of the PAGS and the phase fraction formed during the previous welding. This methodology was applied to single pass and multi pass welding. In both cases, the microhardness values were compared with the experimental results, and good agreement was observed, validating the precision of the calculated phase fraction and the reliability of the methodology. The results show that the methodology can provide valuable insights into phase transformation during welding. Furthermore, this study highlights the potential of this methodology to characterize and optimize the properties of multi pass welded joints under various welding conditions. 용접 시 반복적인 가열과 냉각은 용접부에 다양한 미세조직과 기계적 특성을 형성시키며, 이는 용접부의 특성을 실험적으로 분석하기 어렵게 한다. 본 연구에서는 용접부 모든 위치에서 상변화 거동과 상분율, 경도를 예측하는 방법론을 제시한다. 이 방법론는 오스테나이트 분해 데이터베이스(Austenite decomposition database, AD data)구축, 열 전달 해석, 상변화 변수 예측, 상분율 및 경도 예측 과정이 포함된다. 오스테나이트 분해 데이터베이스는 넓은 범위의 오스테나이트 입자 크기 (Prior austenite grain size, PAGS) 및 t8/5 (800도에서 500도까지의 냉각 속도) 값을 포함하므로 다양한 용접 조건에서 정확한 상 예측을 가능하게 한다. 열전달 모델을 활용해서는 용접 시 용접부에서의 열전달 현상을 해석해 온도이력을 얻는다. 이 온도 이력은 상변화 예측 모델에서 중요한 변수(오스테나이트 분율, PAGS 및 t8/5)를 계산하는데 활용된다. 최종적으로 오스테나이트 분해 데이터베이스에 상변화 변수를 적용해 상분율을 예측하며 예측된 상분율과 각 상의 경도 값을 결합하여 경도를 예측한다. 연구 초기 단일 패스 용접부 예측을 위해 설계된 방법론은 다층 패스 용접부에 활용될 수 있도록 발전되었다. 다층 패스 용접부 예측을 위해 발전된 방법론은 반복적인 용접 상변화 과정을 고려하였으며, 이전 용접 시 형성된 PAGS 및 상분율의 영향을 방법론에 적용하였다. 본 연구에서 제시한 방법론의 검증을 위해 단일 및 다층 패스 용접부에 초기 방법론 및 확장된 방법론을 각각 적용하였다. 단일 패스와 다층 패스 모두에서 예측한 경도값이 실험 결과와 일치하였으며, 이는 예측된 상분율 뿐만 아니라 초기 방법론 및 확장된 방법론의 신뢰성을 증명한다. 또한 이 방법론은 용접 시 상변화에 대한 중요한 이해를 제공하며, 다양한 용접 조건에서의 용접부 접합 특성을 효과적으로 분석하는데 활용될 수 있음을 보여준다.