• 한국운동역학회지
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• 제15권1호
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• pp.29-44
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• 2005

The purpose of this study is to reveal the effects of two different kicks, the drop kick and the punt kick, into the kicking motion, through the kinetic comparative analysis of the kicking motion, which is conducted when one kicks a soccer goal. To grasp kinetic changing factors, which is performed by individual's each body segment, I connected kicking motions, which were analyzed by a two dimension co-ordination, into the personal computer to concrete the digits of it and smoothed by 10Hz. Using the smoothed data, I found a needed kinematical data by inputting an analytical program into the computer. The result of comparative analysis of two kicking motions can be summarized as below. 1. There was not a big difference between the time of the loading phase and the time of the swing phase, which can affect the exact impact and the angle of balls aviation direction. 2. The two kicks were not affected the timing and the velocity of the kicking leg's segment. 3. In the goal kick motion, the maximum velocity timing of the kicking leg's lower segment showed the following orders: the thigh(-0.06sec), the lower leg(-0.05sec), the foot(-0.018sec) in the drop kick, and the thigh(-0.06sec), the lower leg(-0.05sec), the foot(-0.015sec) in the punt kick. It showed that whipping motion increases the velocity of the foot at the time of impact. 4. At the time of impact, there was not a significant difference in the supporting leg's knee and ankle. When one does the punt kick, the subject spreads out his hip joint more at the time of impact. 5. When the impact performed, kicking leg's every segment was similar. Because the height of the ball is higher in the punt kick than in the drop kick, the subject has to stretch the knees more when he kicks a ball, so there is a significant affect on the angle and the distance of the ball's flying. 6. When one performs the drop kick, the stride is 0.02m shorter than the punt kick, and the ratio of height of the drop kick is 0.05 smaller than the punt kick. This difference greatly affects the center of the ball, the supporting leg's location, and the location of the center of gravity with the center of the ball at the time of impact. 7. Right before the moment of the impact, the center of gravity was located from the center of the ball, the height of the drop kick was 0.67m ratio of height was 0.37, and the height of the punt kick was 0.65m ratio of height was 0.36. The drop kick was located more to the back 0.21m ratio of height was 0.12, the punt kick was located more to the back 0.28m ratio of height was 0.16. 8. There was not a significant difference in the absolute angle of incidence and the maximum distance, but the absolute velocity of incidence showed a significant difference. This difference is caused from that whether players have the time to perform of not; the drop kick is used when the players have time to perform, and punt kick is used when the players launch a shifting attack. 9. The surface reaction force of the supporting leg had some relation with the approaching angle. Vertical reaction force (Fz) showed some differences in the two movements(p<0.05). The maximum force of the right and left surface reaction force (Fx) didn't have much differences (p<0.05), but it showed the tendency that the maximum force occurs before the peak force of the front and back surface (Fy) occurs.

• KDI Journal of Economic Policy
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• 제13권2호
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• pp.3-19
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• 1991

인플레기대심리(期待心理)의 지속으로 통화량규제(通貨量規制)의 중요성이 부각되는 가운데 투자금융회사의 업종전환(業種轉換), 금리자유화추진(金利自由化推進) 등으로 각종 통화지표(通貨指標)의 움직임이 불안정해질 우려 때문에 통화정책운용(通貨政策運用)에 어려움을 주고 있다. 그러나 본고(本稿)의 연구결과(硏究結果)에 의하면 70년대 중반 이후 금융환경(金融環境)이 급변하여 왔음에도 불구하고 실질(實質)M2는 실질(實質)GNP 및 기회비용(機會費用)(예상(豫想)인플레율(率)에서 M2가중평균수신금리(加重平均受信金利)를 뺀 것)과 장기적으로 안정적인 관계를 가지며, 이는 유통속도(流通速度)와 기회비용간(機會費用間)의 정(正)의 장기적 균형관계로 간략화 시킬 수 있는 것으로 나타났다. 따라서 사안(事案)의 성격에 따라서 다르겠으나 앞으로의 금융구조변화(金融構造變化)가 반드시 M2유통속도(流通速度)의 움직임을 불안정하게 할 것으로 미리 단정할 필요는 없겠다. 또한 예상(豫想)인플레율(率)이 M2가중평균수신금리(加重平均受信金利)를 지속적으로 상회한다면 유통속도(流通速度)도 그 간의 하락추세에서 벗어나 궁극적으로 상승하게 되며, 이는 기존의 금융정책기조(金融政策基調)의 변화를 요구하는 것이다. 즉 금리자유화(金利自由化)가 이루어져 있지 않은 현여건(現與件) 하에서나 혹은 향후(向後)에 일부(一部) 금리(金利)만을 자유화할 경우에는 정책당국이 시장기능(市場機能)을 대신하여 예상(豫想)인플레율(率)의 변화를 감안하여 수신금리(受信金利)를 수시로 조정하여야 한다. 또한 실물적(實物的) 요인(要因)이 아닌 금융산업개편(金融産業改編)과 같은 금융적(金融的) 요인(要因)에 의한 통화증가가능성(通貨增加可能性)이 존재한다면 수신금리(受信金利)를 탄력적(彈力的)으로 상향조정함으로써 실물경제(實物經濟)에 대한 충격을 최소화하는 등 금리정책(金利政策)의 중요성을 제고하여야 한다.

• 한국수자원학회논문집
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• 제47권5호
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• pp.459-468
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• 2014

수제는 일반적으로 하천에서의 흐름 방향과 유속을 제어하여 하안 또는 제방을 유수에 의한 침식작용으로부터 보호하기 위한 목적으로 설치될 뿐만 아니라 운하의 운영을 위한 충분한 수심 확보 목적으로도 이용된다. 특히 하천복원 및 자연하천 정비에 대한 관심이 커지면서 수제는 국부적인 흐름제어와 수중서식처 조성을 위한 주요 수공구조물로 제시되고 있다. 수제는 단일구조물로 설치되는 경우보다는 군수제의 형태로 설치되어 지는데 군수제의 경우 설치간격에 따라 수제역내 흐름이 다양하게 변화하기 때문에 수제간격은 군수제 설계에 있어서 가장 중요한 설계인자라 할 수 있다. 본 연구에서는 설치간격에 따라 다양하게 변화되는 수제주변 및 수제역내 흐름에 대한 검토를 통해 상향수제를 대상으로 수제설치에 따른 적절한 간격을 제시하고자 하였다. 이를 위해 주흐름영역과 재순환영역으로 구분하여 수제주변에서 발생하는 흐름을 대상으로 검토하였다. 주흐름영역은 통수능 저감으로 인해 증가된 유속이 하상안정성에 영향을 미치는 인자로 설치간격에 따른 최대유속의 변화에 대하여 검토하였다. 수제역내 재순환흐름은 수제역내 세굴 및 퇴적에 영향을 미치는 요소로서 수제역내 흐름 및 제방의 안정성에 문제를 야기시킬 수 있다. 재순환영역은 회전류의 규모와 제방부 안정성에 영향을 미치는 제방주변에서의 흐름에 대하여 분석하였으며, 수제역내 발생하는 회전류의 중심점 위치변화에 대한 비교검토를 수행하였다. 결과를 종합적으로 검토한 결과 상향수제설치에 따른 유속저감, 하상안정성확보, 수제역내역류로 인한 제방안정성 확보 등을 고려하였을 때 적절한 설치간격은 최소 4배에서 최대 6배 이내로 설치할 것을 제안하고자 한다.

• 천문학회지
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• 제29권spc1호
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• pp.63-64
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• 1996

The nature of distant faint blue field galaxies remains a mystery, despite the fact that much attention has been devoted to this subject in the last decade. Galaxy counts, particularly those in the optical and near ultraviolet bandpasses, have been demonstrated to be well in excess of those expected in the 'no-evolution' scenario. This has usually been taken to imply that galaxies were brighter in the past, presumably due to a higher rate of star formation. More recently, redshift surveys of galaxies as faint as B$\~$24 have shown that the mean redshift of faint blue galaxies is lower than that predicted by standard evolutionary models (de-signed to fit the galaxy counts). The galaxy number count data and redshift data suggest that evolutionary effects are most prominent at the faint end of the galaxy luminosity function. While these data constrain the form of evolution of the overall luminosity function, they do not constrain evolution in individual galaxies. We are carrying out a series of observations as part of a long-term program aimed at a better understanding of the nature and amount of luminosity evolution in individual galaxies. Our study uses the luminosity-linewidth relation (Tully-Fisher relation) for disk galaxies as a tool to study luminosity evolution. Several studies of a related nature are being carried out by other groups. A specific experiment to test a 'no-evolution' hypothesis is presented here. We have used the AUTOFIB multifibre spectro-graph on the 4-metre Anglo-Australian Telescope (AAT) and the Rutgers Fabry-Perot imager on the Cerro Tolalo lnteramerican Observatory (CTIO) 4-metre tele-scope to measure the internal kinematics of a representative sample of faint blue field galaxies in the red-shift range z = 0.15-0.4. The emission line profiles of [OII] and [OIII] in a typical sample galaxy are significantly broader than the instrumental resolution (100-120 km $s^{-l}$), and it is possible to make a reliable de-termination of the linewidth. Detailed and realistic simulations based on the properties of nearby, low-luminosity spirals are used to convert the measured linewidth into an estimate of the characteristic rotation speed, making statistical corrections for the effects of inclination, non-uniform distribution of ionized gas, rotation curve shape, finite fibre aperture, etc.. The (corrected) mean characteristic rotation speed for our distant galaxy sample is compared to the mean rotation speed of local galaxies of comparable blue luminosity and colour. The typical galaxy in our distant sample has a B-band luminosity of about 0.25 L$\ast$ and a colour that corresponds to the Sb-Sd/Im range of Hub-ble types. Details of the AUTOFIB fibre spectroscopic study are described by Rix et al. (1996). Follow-up deep near infrared imaging with the 10-metre Keck tele-scope+ NIRC combination and high angular resolution imaging with the Hubble Space Telescope's WFPC2 are being used to determine the structural and orientation parameters of galaxies on an individual basis. This information is being combined with the spatially resolved CTIO Fabry-Perot data to study the internal kinematics of distant galaxies (Ing et al. 1996). The two main questions addressed by these (preliminary studies) are: 1. Do galaxies of a given luminosity and colour have the same characteristic rotation speed in the distant and local Universe? The distant galaxies in our AUTOFIB sample have a mean characteristic rotation speed of $\~$70 km $s^{-l}$ after correction for measurement bias (Fig. 1); this is inconsistent with the characteristic rotation speed of local galaxies of comparable photometric proper-ties (105 km $s^{-l}$) at the > $99\%$ significance level (Fig. 2). A straightforward explanation for this discrepancy is that faint blue galaxies were about 1-1.5 mag brighter (in the B band) at z $\~$ 0.25 than their present-day counterparts. 2. What is the nature of the internal kinematics of faint field galaxies? The linewidths of these faint galaxies appear to be dominated by the global disk rotation. The larger galaxies in our sample are about 2"-.5" in diameter so one can get direct insight into the nature of their internal velocity field from the $\~$ I" seeing CTIO Fabry-Perot data. A montage of Fabry-Perot data is shown in Fig. 3. The linewidths are too large (by. $5\sigma$) to be caused by turbulence in giant HII regions.

• 조명전기설비학회논문지
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• 제20권4호
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• pp.43-48
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• 2006

풍력 발전 시스템과 태양광 발전 시스템을 상호 보완함으로써 안정적인 전력 공급과 에너지 이용 효율의 향상을 꾀할 수 있는 풍력-태양광 복합발전 시스템에 대한 관심이 고조되고 있다. 본 연구에서는 이러한 복합 발전 시스템을 효율적이고 안정적으로 운용하기 위하여 시스템의 각종 데이터들을 수집, 분석하고 파일로 저장하며 이를 인터넷을 이용하여 원격지에서도 모니터링 할 수 있는 시스템을 구축한다. 교류와 직류의 각종 전압, 전류들을 비롯한 풍속, 조도, 온도 등의 물리량을 측정하기 위하여 여러 형태의 변환기를 사용하였고 신호 조절 회로를 구성하였다. 데이터 수집 보드를 이용하여 컴퓨터로 데이터들을 저어 들였으며, 시스템 운용을 위한 서버 프로그램과 이를 원격지에서 실시간 모니터링 및 저장된 데이터들을 다운로드 할 수 있는 클라이언트 프로그램을 개발하였다. 측정된 데이터를 시간, 기상 등의 여러 조건과 연관하여 분석하였다.

• 대한기계학회논문집B
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• 제34권2호
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• pp.197-202
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• 2010

자발 진동하는 층류 예혼합 분젠 화염을 관찰하기 위하여 분기관을 가진 연소기를 제작 하였다. 특히, 조건에 따른 화염 거동을 살펴봤으며, 화염 표면적과 열발생 변동의 관계에 대하여 고찰하였다. 본 연구에서 사용된 당량비는 1.1 이고, 노즐 출구 평균 유속은 1.75 m/sec 이다. 연소 챔버와 분기관의 길이비(L.R.)는 연소기 내 압력 변동에 영향을 미치며, 결과적으로 화염 거동 특성이 달라짐을 관찰하였다. 또한, 간섭 필터의 유무에 따른 $OH^*$, $CH^*$, 그리고 화염 자발광은 정성적으로 유사한 거동을 나타냈으며, 자발 진동하는 층류 예혼합 분젠 화염의 화염 표면적 변동과 열발생 변동은 선형적인 관계를 가짐을 확인하였다.

• 한국항해항만학회지
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• 제37권1호
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• pp.79-84
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• 2013

도서지역에 대한 에너지공급시스템의 다양화를 위해서는 지역 내에 풍부한 자연에너지 활용이 필요하고 이를 통해 도서주민의 생활환경 개선이 가능하다. 이에 본 연구에서는 지역에 특화된 자연에너지를 이용한 전력공급시스템을 제안하기 위한 기초자료 구축을 목적으로 통영-남해 해역에 위치한 4개 섬의 풍력과 일사량을 1년간 (2010년 11월~2011년 10월) 실측하여 발생 특성을 파악하고 활용가능성을 비교 평가하였다. 본 연구의 성과를 정리하면 다음과 같다. 풍향별 발생 빈도수를 이용하여 작성한 바람장미로 부터 4개 섬의 풍향 특성이 크게 다르다는 것을 알았다. Rayleigh 속도확률분포를 이용한 평가에 따르면 KR섬과 SS섬은 2~5m/s의 바람이 많이 불지만, SR섬과 YJ섬은 2m/s이하의 저속 바람의 발생 확률이 매우 높은 것으로 분석되었고, 4개 섬 각각의 풍력발전량에는 큰 차이가 있었다. 4개 섬 모두에서 최대 일일 일사량은 2011년 7월에 발생하였지만, 평균 일일 일사량은 2011년 4월이 가장 컸다. 또한 월별 누적 일사량의 경우 2011년 4월이 가장 많았고, 2010년 12월 가장 적었다.

• 대한치과교정학회지
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• 제7권1호
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• pp.13-22
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• 1977

The author investigated the timing of land and wrist ossification events taking place in the hamate and pisiform by means of roentgenographic examination and its relation to the peak growth velocities in body height. Materials obtained included 493 sheets of X-ray films taken from 257 boys ana 236 girls aged between 7 and 17 years lived in Seoul area. The results indicate that; 1) The average ages at occurrence of initial ossification of the hook of the hamate were 12 years 3 months in boys and 10 years 1 month in girls. 2) The average ages at which advanced ossification of the hook of the hamate occurred were 13 years 7 months in boys and 11 years 11 months in girls. 3) Initial ossification of the pisiform appeared at 13 years 0 month in boys and 10 years 2 months in girls. 4) All three ossification events in hand and wrist, and peak growth velocity in body height occurred earlier in girls than in boys. 5) Initial ossification in the hook of the hamate and pisiform preceded or coincided with peak growth in body height in most boys and girls, on the other hand, advanced ossification in the hook of the hamate occurred around peak growth in body height but in girls did it after peak growth in body height. 6) It would appear that initial ossification in the hook of the hamate or in the pisiform, both for boys and girls, provides a better indication of approaching peak adolescent growth in body height. 7) Advanced ossification in the hook of the tamale would indicate that the period of cercumpuberal peak growth had teen entered or finished.

• 천문학회지
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• 제38권2호
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• pp.215-218
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• 2005

An atlas of high resolution (${\lambda}/{\Delta}{\lambda}$=45,000) profiles of interstellar atomic lines of K I (7665, 7699 ${\AA}$), Na I (D 1, D2), Ca II (H, K), Ca I (4227 ${\AA}$), molecular structures of CH, CH+, CN and the major diffuse interstellar bands at 5780 and 5797 ${\AA}$ based on ${\~}$300 echelle spectra of ${\~}$200 OB stars is presented. Relationships between the reddenings, distances and equivalent widths of NaI, CaII, KI, CH, CH+, CN and diffuse bands are discussed. The equivalent width of K I (7699 ${\AA}$) as well as of CH4300 ${\AA}$ / correlate very tightly with E(B- V) in contrast to the features of neutral sodium, ionized calcium and the molecular ion CH+. The equivalent widths of the Hand K lines of Call grow with distance at a rate ${\~}$250m${\AA}$ per 1 kpc. A similar relation for NaI is much less tight. The strengths of neutral potassium lines, molecular features and diffuse interstellar bands do not correlate practically with distance. These facts suggest that ionized calcium fills the interstellar space quite homogeneously while the other carriers mentioned above, especially K I, CH and these of diffuse bands occupy more and more compact volumes, also filled with dust grains. Apparently the carriers of narrow diffuse bands are spatially correlated with simple molecules and dust grains - all abundant in the so-called 'zeta' type clouds. The same environment seems to be hostile to the carriers of broad diffuse interstellar bands (DIEs) (like 5780 or 6284) and -to a certain extent - also to CaII, NaI and CH+.

• 천문학회보
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• 제38권2호
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• pp.63.1-63.1
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• 2013

We present the results of time monitoring observations of $^{28}SiO$ v = 1, 2, J = 1-0, $^{29}SiO$ v = 0, J = 1-0 and $H_2O$ $6_{16}-5_{23}$ maser lines toward radio Source I in Orion KL. The observations have been performed from 2009 June to 2013 April using the 21m single dish radio telescopes of the Korean VLBI Network. Both SiO and $H_2O$ maser lines were simultaneously obtained at 20 epochs. In particular, the third outburst of $H_2O$ maser emission (the first: 1985, the second: 1998) was detected and the flux density variation curve was obtained. The maximum flux density flared up to an order of $10^5$ Jy during 2012 May-July at peak velocity of 7.33 km $s^{-1}$. Hirota et al. (2011) reported that the bursting maser features are located at 8" from Source I and coincident with the interacting region between the outflow from Source I and a dense ambient gas, Orion Compact Ridge. In the case of SiO masers arising from close to the Source I, the peak emission of the v = 1, J = 1-0 maser line appeared in 2010 April. We are investigating the possible relation between this SiO maser peak emission and the third $H_2O$ maser flaring.