• Title/Summary/Keyword: dynamic period

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The Change of Motion Ranges of Adjacent Vertebral Joints after Lumbar Fusion Operation (요추 고정수술 후 인접척추 운동범위의 변화)

  • Yeo, Sang-Jun;Park, Seung-Won;Kim, Young-Baeg;Hwang, Sung-Nam;Choi, Duck-Young;Suk, Jong-Sik;Chung, Dong-Kue;Min, Byung-Kook
    • Journal of Korean Neurosurgical Society
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    • v.29 no.11
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    • pp.1456-1460
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    • 2000
  • Objectives : Transpedicular screw fixation has become an important method for internal fixation in variety of disorders. However, acceleration of degeneration at the adjacent segment in any follow. The goal of this study is to review the change of motion ranges of vertebral joints adjacent to fused level in lumbar spine. Methods : This study consists of 22 patients with degenerative spinal instability. Treatment of spinal instability includes posterior fusion with transpedicular screw fixation or transpedicular screw fixation with posterior lumbar interbody fusion. The flexion-extension angle(FEA) was measured from dynamic views of lumbar spine taken both at preoperative and post operative period. Results : The FEA of upper vertebral joint adjacent(FEA-u) to a fused L4-5 level was increased(p=0.010). The FEA-u was increased in case of L5-S1 fusion(p=0.025). The change of FEA-u in case of L5-S1 fusion was greater than that in L4-5 fusion(p=0.013). Conclusion : After L4-5 fusion, there seems to be more meaningful increase in FEA of L3-4 than that of L5-S1. The reason may be due to the damage of L3-4 facet joints during the operation, the other possible explanation may be the anatomical stability of L5-S1 vertebral joint. The change of FEA-u of L5-S1 fusion is increased more than that of L4-5 fusion. Because there are compensations in the adjacent vertebrae both above and below the fused L4-5, the compensatory motion in FEA-u of L5-S1 fusion was greater than that of the L4-5 fusion.

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The Characteristics of Colors Found in the Gyubang Culture of Joseon Dynasty (조선시대 규방문화에 표현된 색채특성)

  • Kim, Eun-Kyoung;Kim, Young-In
    • Journal of the Korean Society of Costume
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    • v.59 no.3
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    • pp.109-130
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    • 2009
  • This study examines the rotor characteristics of Guybang culture (women's living in Joseon) relics which the life images and mental world of women in Joseon if expressed to prepare rotor data to be utilized in modern design and information for color identity establishment of Korean women culture. The result of this study is as following: 1. From 176 pieces of relic photos, total of 1380 color chips were extracted. For color analysis, 1368 units (99.1%) of color data excluding achromatic 12 units (0.9%) among 1380 units of colors were used. With the standard of 10 color wheel of Munsell Color System, the result of studying distributions according to frequency, red was the highest by 25.9%, yellow was 21.4% in women's goods in Joseon period which the ratio of red and yellow was 473%. Other than that, GY 14.6%, YR 11.3% and RP 11.1% followed next which is studied that the warm colors that conveys enjoyable and glamorous feelings composed 84.3%; 2. As a result of tone analysis, high value low chroma ltg color showed highest distribution of 20% and d was 12.2%, b was 11.7% and sf was 8.8%. Generally, it showed high frequency in high value cocors such as ltg, sf and b of 40.5%t and in low chroma (ltg) and medium chroma (d, sf) of 41% and colors in bright and calm image was used the most. 3. As a result of analyzing relationship between hue & tone, the ltg tone of Y close to white in traditional color sensibility showed the highest frequency of 9.6% and ltg tone of GY(6.4%), b tone of RP(6.1%), and v(5.4%), b(5.4%), dp(5.3%) of R followed next. 4. As a result of analyzing the characteristics of coloring, it showed that in case of coloring contrasting hues, it is adjusted similar tones and in case of coloring less contrasting hue, the difference in tone is adjusted to be rather large to make harmonized coloring. Moreover, in case of coloring similar hues, the ratio of using same tone and similar tone was large which the coloring of calm image and dynamic image is all used.

An Estimation of Occupancy Population Using the Expanded Mobile Phone Data (이동통신 자료 전수화를 통한 존재인구 산정 방안)

  • KIM, Kyoung Tae;LEE, Inmook;KWAK, Ho-Chan;MIN, Jae Hong
    • Journal of Korean Society of Transportation
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    • v.34 no.3
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    • pp.222-233
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    • 2016
  • Recently, mobile phone data was applied in travel demand modeling as a new source of dynamic population movement. This study is also aimed to estimate "occupancy population" during a given period of time within a given spatial region using mobile phone data. An occupancy population was defined as the number of people residing or moving within a given time and space. In case of Seoul Metropolitan area, we divided the area into a number of administrative districts as zones for analysis and estimated the occupancy population of each zone by mobile phone data collected by SK telecom Co., a wireless telecommunication provider in Korea. For the expansion of mobile phone data, a new concept of "communication probability" was introduced and applied in the estimation of occupancy population of each zone by the hour. We compared the estimated number with the daytime population and the daytime population index referred by the Statistics Korea. The results showed that a positive correlation existed between the estimated number and the statistical number by nationwide survey. It was concluded that mobile phone data could be more cost-effective sources than a conventional survey method to estimate the pattern of population movement by the hour or by the day.

The effects of employment on depression -the Korea Welfare Panel Study- (고용상태 변화와 고용지위가 우울에 미치는 영향 -한국복지패널을 중심으로-)

  • Yoo, Kyuong-Ar;Kim, Young-Ran;Park, Chang-Soo;Lee, Tae-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.251-259
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    • 2018
  • This study was conducted to investigate individuals' mental health on the basis of scores for depression and self-esteem from the Korea Welfare Panel Study (KWPS) and determine their dynamic association with employment status. This study was conducted using the eighth (2013) and ninth (2014) data from the KWPS. To identify factors affecting depression, socio-demographic factors, factors related to mental health, and contents related to employment, such as changes in the employment condition and employment status, were selected and analyzed by t-test, ANOVA, and hierarchial multiple regression to determine the explanatory power. Multiple regression revealed that in Model 1, those who were female, were older, had no spouse, were in the lower income bracket, had lower total self-esteem, and scored higher for depression in the previous period tended to show higher levels of depression. Education had no significant effect and explanatory power for all variables inputted into this model was estimated to be 30.8% (p<0.001). The explanatory power for all variables input into Model 2, which was generated by inputting employment status into Model 1, was estimated to be 30.9%, which was 0.1% higher than for Model 1 (p<0.05). These results indicated that depression was significantly correlated with gender, age, income, presence of a spouse, previous depression, self-esteem, and employment status; accordingly, investigation of the factors that can narrow the gap among variables affecting depression should be conducted and socially supported.

The Early Result of Anterior Rotational Osteotomy in the Treatment of Osteonecrosis of the Femoral Head (대퇴골두 무혈성괴사의 치료에서 전방 회전 절골술의 조기 추시 결과)

  • Kim, Se-Dong;Shin, Duk-Seop;Jang, Woo-Seok
    • Journal of Yeungnam Medical Science
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    • v.11 no.2
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    • pp.284-292
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    • 1994
  • In transtrochanteric rotational osteotomy to treat osteonecrosis of the femoral head, the necrotic superior anterior femoral head is rotated anteriorly around the longitudinal neck axis so that the weight bearing force is transferred to the intact posterior surface. The ratio of transposed intact articular surface of the femoral head to the weight-bearing surface of the acetabulum on postoperative anteroposterior view of the hip roentgenograph is the most important indicator of the prognosis. During the period from December 1992 to June 1994, we treated 31 hips in 28 patients who were indicated for the anterior rotational osteotomy among the patients of osteoncrosis of the femoral head. Among the patients, male were 27 and female was one. Age distribution was from 13 to 62 years old and mean age was 44.3. According to the Ficat and Arlet classification, II A was most in number as 16 II B was 7 and III was 8. As their etiolgic factors, alcohol was most in number as 18, steroid was 3, idiopathic was 5 and trauma was 2. The mean rate of the intact area of the posterior part of the femoral head to the total articular surface on the preoperative lateral view of the hip roentgenograph was 41.8%, The mean ratio of transposed intact articular surface of the femoral head to the weight bearing surface of the acetabulum was 53.8%, Fixation devices were screws or dynamic hip screw.

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DIAGNOSTICS OF PLASMA INDUCED IN Nd:YAG LASER WELDING OF ALUMINUM ALLOY

  • Kim, Jong-Do;Lee, Myeong-Hoon;Kim, Young-Sik;Seiji Katayama;Akira Matsunawa
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.612-619
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    • 2002
  • The dynamic behavior of Al-Mg alloys plasma was very unstable and this instability was closely related to the unstable motion of keyhole during laser irradiation. The keyhole fluctuated both in size and shape and its fluctuation period was about 440 ${\mu}{\textrm}{m}$. This instability has been estimated to be caused by the evaporation phenomena of metals with different boiling point and latent heats of vaporization. Therefore, the authors have conducted the spectroscopic diagnostics of plasma induced in the pulsed YAG laser welding of Al-Mg alloys in air and argon atmospheres. In the air environment, the identified spectra were atomic lines of Al, Mg, Cr, Mn, Cu, Fe and Zn, and singly ionized Mg line, as well as strong molecular spectrum of AlO, MgO and AIH. It was confirmed that the resonant lines of Al and Mg were strongly self-absorbed, in particular in the vicinity of pool surface. The self-absorption of atomic Mg line was more eminent in alloys containing higher Mg. These facts showed that the laser-induced plasma was relatively a low temperature and high density metallic vapor. The intensities of molecular spectra of AlO and MgO were different each other depending on the power density of laser beam. Under the low power density irradiation condition, the MgO band spectra were predominant in intensity, while the AlO spectra became much stronger in higher power density. In argon atmosphere the band spectra of MgO and AlO completely vanished, but AlH molecular spectra was detected clearly. The hydrogen source was presumably the hydrogen solved in the base Metal, absorbed water on the surface oxide layer or H$_2$ and $H_2O$ in the shielding gas. The temporal change in spectral line intensities was quite similar to the fluctuation of keyhole. The time average plasma temperature at 1 mm high above the surface of A5083 alloy was determined by the Boltzmann plot method of atomic Cr lines of different excitation energy. The obtained electron temperature was 3, 280$\pm$150 K which was about 500 K higher than the boiling point of pure aluminum. The electron number density was determined by measuring the relative intensities of the spectra1lines of atomic and singly ionized Magnesium, and the obtained value was 1.85 x 1019 1/㎥.

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A Link Travel Time Estimation Algorithm Based on Point and Interval Detection Data over the National Highway Section (일반국도의 지점 및 구간검지기 자료의 융합을 통한 통행시간 추정 알고리즘 개발)

  • Kim, Sung-Hyun;Lim, Kang-Won;Lee, Young-Ihn
    • Journal of Korean Society of Transportation
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    • v.23 no.5 s.83
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    • pp.135-146
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    • 2005
  • Up to now studies on the fusion of travel time from various detectors have been conducted based on the variance raito of the intermittent data mainly collected by GPS or probe vehicles. The fusion model based on the variance ratio of intermittent data is not suitable for the license plate recognition AVIs which can deal with vast amount of data. This study was carried out to develop the fusion model based on travel time acquired from the license plate recognition AVIs and the point detectors. In order to fuse travel time acquired from the point detectors and the license plate recognition AVIs, the optimized fusion model and the proportional fusion model were developed in this study. As a result of verification, the optimized fusion model showed the superior estimation performance. The optimized fusion model is the dynamic fusion ratio estimation model on real time base, which calculates fusion weights based on real time historic data and applies them to the current time period. The results of this study are expected to be used effectively for National Highway Traffic Management System to provide traffic information in the future. However, there should be further studies on the Proper distance for the establishment of the AVIs and the license plate matching rate according to the lanes for AVIs to be established.

Investigation of Fatigue Damage of the Mooring Lines for Submerged Floating Tunnels Under Irregular Waves (불규칙 파랑 중 해중 터널 계류선의 단기 피로 손상 분석)

  • Kim, Seungjun;Won, Deok Hee
    • Journal of Korean Society of Steel Construction
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    • v.29 no.1
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    • pp.49-60
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    • 2017
  • As well as the strength check, fatigue life check is also mainly required for designing mooring lines of the floating structures. In general, forces which induce dynamic structural response significantly affect to fatigue design of the mooring lines. So, waves are mainly considered as the governing loading for fatigue design of the mooring lines. In this study, characteristics of the fatigue damage of the mooring lines for submerged floating tunnels (SFT) under irregular waves are investigated. For this study time domain hydrodynamic analysis is used to obtain motion of the tunnel and tension and stresses of the mooring lines under the specific environmental conditions. Also, the Rainflow-counting method, the Palmgren-Miner's rule, and S-N curves for floating offshore structures presented by DNV recommendation is applied to calculate the fatigue damage due to the fluctuating stresses. Referring to the design plactice of the tendon pipes for TLP (tension-leg platform), which is very similar structural system to SFT, it is assumed that a 100 year return period wave attacks the SFT systems during 48 hours and the fatigue damages due to the environmental loading are calculated. Following the analysis sequence, the effects of the tunnel draft, spacing and initial inclination angle of the mooring lines on the fatigue damage under the specific environmental loadings are investigated.

Analysis of Snowfall Development Mechanism over the Korean Peninsula due to Polar Low (극저기압에 의한 한반도 강설 발달기구 분석)

  • Kim, Jinyeon;Min, Ki-Hong
    • Journal of the Korean earth science society
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    • v.34 no.7
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    • pp.645-661
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    • 2013
  • The synoptic, thermodynamic, and dynamic characteristics of a heavy snowfall event that occurred in Seoul metropolitan area on 27 to 28 December 2010 was investigated. During this period there was a distinctive case that was identified as a polar low. We analyzed surface and upper level weather charts, snowfall amount, sea surface temperature, satellite imagery, sounding, and the National Center for Environmental Prediction global $1^{\circ}{\times}1^{\circ}$ reanalysis data. The polar low developed in an area where there was strong baroclinicity in the lower level aided by strong conditional instability due to 925 hPa warm air advection and 700 hPa cold air advection. The development mechanism of polar low is due, in part, to the tropopause folding, which advected stratospheric air increasing potential vorticity in mid-level and inducing cyclonic vorticity and convergence in low-level. Eventually clouds developed and there were snowfall total of 10 cm in Seoul metropolitan area and as much as 20 cm in southern parts of Korea. During the snowfall development, there was a $-45^{\circ}C$ cold core at 500 hPa and shortwave maintained $3-5^{\circ}$ separation with surface trough, which favored the development of polar low located in the warm sector and cyclonic advection area. The height of the dynamical tropopause lowered to 700 hPa during the peak development and increase in potential vorticity allowed strong vertical motion to occur. Overall, there was a close relationship between the development of snowfall and tropopause undulation. The heaviest snowfall occurred east of the tropopause folding where strong cyclonic vorticity, vertical motion, and moisture advection all coincided while the polar low was passing through the Korean peninsula.

Study on the Styles of Subcultural Clothing: from 1930s to 1990s (하위문화 맥락에서 본 패션스타일 연구)

  • 양미경
    • Journal of the Korea Fashion and Costume Design Association
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    • v.5 no.1
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    • pp.33-45
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    • 2003
  • This is a study that examines the fashion changes in the 20th century in terms of various subcultures in the period. Starting from defining the concept and the developing process of subculture, this study traces the history of subcultural styles from 1930s to 1990s, focusing on the way each generation resisted the main stream through its styles. This study is intended to provide a theoretical frame on the understanding of subcultural styles, with a close examination of its formative and developing process and characteristics. This study understands subcultural style as a way of deviate or resistant expression within a society. It differentiates itself from the main style by deliberately and publicly asserting its own identity, and, as a result, realizes in the form of fashion its repressed subconsciousness, resistance to the alienation from the society, and deviation from the normative ethics and morality of a society. The four types of subcultural styles presented in chapter 4 are based on their form of resistance, and they are classified and analyzed as follows: The first type is revision, which tries to revise and change the given form by adding new elements. There are two kinds of revision, one is dressing up, which dresses for success, and the other is minimal dressing. Hyperbole is the second type, which resists by emphasizing or hyperbolizing the main stream with its erotic, nihilistic, or dynamic forms. Two kinds of hyperbole are examined, one is hyperbole of masculinity, and the other is ostentatious hyperbole. The third type is reversal and rejection, which reverses the forms from the established sign system into its own secret code, or rejects the traditional taboos. This type include no dressing, and the reversal of sex identity. Isolation and redrawal is the fourth type, which tries to distance itself from the ritual code of the day. This type is divided into dressing of the escape from time, and dressing of the escape from space. The first group of this type is characterized by nostalgia or futurism. An emphasis is given on ethnicity, naturalism, or a closed space within a city in dressing of the escape from space. In conclusion, it can be said that subcultural style puts the foremost importance on individual freedom. Since 1990s, the distinction between the subcultural styles and high fashion gets somewhat blurred, while the liberal, sexual, life stylistic tension between the two groups are heightened.

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