• Title/Summary/Keyword: Height changes

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Long-Term Trend of Surface Wind Speed in Korea: Anemometer Height Adjustment (한반도 지상 풍속의 장기 추세 분석: 풍속계 고도 보정)

  • Choi, Yeong-Ju;Park, Chang-Hyun;Son, Seok-Woo;Lee, Jae-Won;Hong, Dong-Chan
    • Atmosphere
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    • v.31 no.1
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    • pp.101-112
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    • 2021
  • The long-term trend of surface wind speed in Korea is examined for 31 KMA weather stations from 1985 to 2019. Most stations, except Daegwallyeong, have several times of anemometer height changes from tens of centimeters to several meters. To minimize such height change effect on long-term wind trend, the present study adjusts anemometer height in each station to the standard height of 10 m using the power-law wind profile. This adjustment results in non-negligible trend change. For instance, the increasing surface wind speed at Suwon station, which has six times of anemometer height changes in a range of 0.8 m to 20 m, is weakened up to 67% and becomes statistically insignificant. Likewise, the decreasing trend at Andong station, with three times of anemometer height changes in a range of 10 m to 15.5 m, is weakened up to 66%. A similar weakening in long-term trend is observed in most stations regardless of positive and negative trends. However, due to the cancellation between weakened negative trends and weakened positive trends, the station-averaged wind speed trend in Korea does not change much. This result suggests that anemometer height adjustment is crucial for evaluating local wind speed trend but its impact on nation-wide wind speed trend is rather minor.

The Effect of Column Height on Sludge-Water Interface Height Change Model (슬러지계면층높이변화모델에서 컬럼높이에 대한 영향)

  • Park, Suk Gyun;Kang, Seon-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.2
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    • pp.265-272
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    • 2006
  • While sludge settles down in a column, sludge settling characteristic is influenced by effect parameters, interparticle force, wall effect etc. As the height of a column changes, the settling velocity of sludge-water interface changes, too. At lower sludge concentration, particular effect was not observed by the difference of column height, however it was observed that settleability of sludge was greatly influenced by column height when sludge settling was poor or sludge concentration was high. It is therefore required to consider the effect of column height when the power model for sludge interface settling is established. In the tests, there was hardly any $SVI_{ts}$(SVI after "t" minutes) difference in each column after 10min at $1.5kg/m^3$ of sludge concentration. When sludge concentration was at $2.5kg/m^3$, $SVI_{ts}$ tended to be constant after 20min. At $3.5kg/m^3$, $SVI_{ts}$ increased to 30minuets. The purpose of this work is to establish the correction factor that is able to compensate the errors derived from each different height of column.

Induced Morphological Changes in Larval Rock Bream, Oplegnathus fasciatus, under Starvation

  • Park, In-Seok;Choi, Hee-Jung;Noh, Choong-Hwan;Myoung, Jung-Goo;Park, Hye Jung;Goo, In Bon
    • Development and Reproduction
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    • v.17 no.4
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    • pp.399-407
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    • 2013
  • Morphological changes in the reared rock bream, Oplegnathus fasciatus, from hatching to six days after hatching were examined during the early growth stage under starvation. All the larvae died within five days when feeding was delayed for three days after hatching. These results imply that initial larval food should be supplied within two days of hatching. Changes in the pectoral angle and the ratios of eye height to head height, gut height to standard length, and gut height to myotome height in the rock bream are alternative indicators for the identification of starving fish. These indicators might prove useful in evaluating the successful transition from endogenous to exogenous feeding in this species.

A LONGITUDINAL STUDY OF KOREAN CHILDREN'S PROFILE CHANGE IN RELATION WITH MANDIBULAR GROWTH PATTERN (한국인 아동의 하악골 성장유형에 따른 안모변화에 관한 누년적 연구)

  • Kim, Ui-Hwan;Ryu, Young-Kyu
    • The korean journal of orthodontics
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    • v.15 no.2
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    • pp.175-195
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    • 1985
  • Vertical and horizontal growth occur in the craniofacial complex which ensues continuous changes in facial morphology, until the end of active growth period. Longitudinal study for individual is essential, in the research on growth and development, however, the difficulties in obtaining long term subjects in Korea, the research has been limited. The author analyzed the cephalometric roentgenogrems of 43 boys and 47 girls taken from the ages 6 to 10. The subjects were divided into 3 groups according to SN-MP angle and 2 groups according to gonial angle. In this longitudinal study, 21 variables were measure 4. The obtained results were as follows: 1. SN-MP angle and genial angle had no significant changes in each group with age. 2. With age, facial convexity of hard tissue decreased in all groups, facial angle of hard tissue increased in low SN-MP angle group, but facial convexity of soft tissue had no significant changes in all groups with age. 3. In comparison of high SN-MP angle group and low SN-MP angle group, the former had greater facial convexity and smaller facial angle than the latter. 4. SN-MP angle and the ratio of posterior dental height to anterior dental height had reverse correlation in all groups. 5. High genial angle group revealed larger SN-MP angle, anterior dental height facial convexity, but smaller mandibular length, and the ratio of posterior dental height to anterior dental height compared with low genial angle group.

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A large eddy simulation on the effect of buildings on urban flows

  • Zhang, Ning;Jiang, Weimei;Miao, Shiguang
    • Wind and Structures
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    • v.9 no.1
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    • pp.23-35
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    • 2006
  • The effect of buildings on flow in urban canopy is one of the most important problems in local/micro-scale meteorology. A large eddy simulation model is used to simulate the flow structure in an urban neighborhood and the bulk effect of the buildings on surrounding flows is analyzed. The results demonstrate that: (a) The inflow conditions affect the detailed flow characteristics much in the building group, including: the distortion or disappearance of the wake vortexes, the change of funneling effect area and the change of location, size of the static-wind area. (b) The bulk effect of the buildings leads to a loss of wind speed in the low layer where height is less than four times of the average building height, and this loss effect changes little when the inflow direction changes. (c) In the bulk effect to environmental fields, the change of inflow direction affects the vertical distribution of turbulence greatly. The peak value of the turbulence energy appears at the height of the average building height. The attribution of fluctuations of different components to turbulence changes greatly at different height levels, in the low levels the horizontal speed fluctuation attribute mostly, while the vertical speed fluctuation does in high levels.

Prediction of Sludge-Water Interface Height Change in Batch Column (Batch Column에서의 슬러지계면층 높이변화 예측)

  • Park, Suk Gyun;Kang, Seon-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.1
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    • pp.156-163
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    • 2006
  • While sludge is settling in batch column, sludge concentration becomes high. Because the characteristic of sludge settling changes in function of time due to the sludge concentration change, the sludge settling velocity changes too. Also, because the sludge settling characteristic is influenced by a physical characteristic of sludge and a column height etc, it is difficult to exactly measure the sludge settling characteristic. Although the sludge volume indexes, SVI, SSVI and $SSVI_{3.5}$, are used to predict sludge settling characteristic, these indexes are not reliable values. Because the previously established models for sludge settling velocity predict the sludge settling velocity only, it is difficult to predict sluge-water interface height by using those models. The purpose of this experiment is to establish the empirical model which predicts the sludge interface height change with respect to the sludge physical characteristic and the settling condition.

An Analysis on the Morphological Relationship of Hair Styles with Changes in Necklines and Collars in 20th Century Fashion

  • Kim, Hyoju;Bae, Soojeong
    • Journal of Fashion Business
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    • v.19 no.3
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    • pp.1-13
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    • 2015
  • The purpose of this research is to analyze the morphological relationship between changes hair styles and changes in necklines and collars in 20th century fashion. After selecting the representative plate by each age for this study, the neckline, collar, and formative relevancy of hair style according to it have been analyzed by measuring the neckline, collar, and the width and height item of each hair style. The results of this study show- that the width changes of necklines and collars were mostly proportional in relation to each other, but the width changes of collars and hair styles were inversely proportional. While the amplitude of necklines and collars' width change was very broad, the amplitude of some hair style's height change was very broad. Regarding width, this result had similar results of the researcher's former research, the relation according to the width of necklines, collars and hair style from 16th century to 19th century. However, regarding height, this result was different from the preceding research in that the amplitude of hair style and collars' height change was very broad between 16th and 19th centuries, but the amplitude of neckline's height change is relatively small. This means various heights of necklines appeared in the 20th century, but more various heights of collars were shown between the 16th and 19th centuries. This research hopes to be helpful by predicting trends in fashion, and to be basic resources to understand the systemic relationship of these factors.

The Effects of a Bridging Exercise Applying Changes in the Base of Support for the Shoulders on Trunk Muscle Activation

  • Lee, Tae-Gyu;Park, Chan-Hyun;Son, Ho-Hee
    • Journal of the Korean Society of Physical Medicine
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    • v.11 no.3
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    • pp.97-104
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    • 2016
  • PURPOSE: Bridge exercise is widely used in rehabilitation exercise for trunk stabilization through various applications in clinical practice. However, there is a lack of studies changing the base of support for the shoulders. The purpose of this study is to investigate the changes in the base of support for the shoulders of trunk muscle activation during bridge exercise. METHODS: 20 healthy subjects (10 men, 10 women) in their twenties were participated in this study. They performed 5 bridge exercises (bridge exercise with their shoulders on a stable table (1/2 knee height, knee height), and on a sling (1/2 knee height, knee height), conventional bridge exercise. The surface electromyography were used for rectus abdominis (RA), internal oblique (IO), external oblique (EO), and erector spinae (ES). RESULTS: During bridge exercise that their shoulders on the sling of 1/2 knee height, the RA, EO, IO muscle activities were significant increased. And during bridge exercise that their shoulders on the stable surface of knee height, the IO/RA ratio were higher than other positions but there were no significant difference between positions for EO/RA, IO/RA ratio. CONCLUSION: Based on this result, using various bases of support and changing the height of bridging exercise may be used to provide effective trunk stabilization exercises.

A Study on How Height and Weight Affects Glomerular Filtration Rate (신장과 체중의 변화가 사구체 여과율에 미치는 영향)

  • Park, A Rang;Choi, Jong Sook;Lee, Young Hee;Jung, Woo Young
    • The Korean Journal of Nuclear Medicine Technology
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    • v.23 no.1
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    • pp.40-44
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    • 2019
  • Purpose Glomerular filtration rate (GFR) is an important index for evaluation of renal function, renal disease diagnosis and progress monitoring. Therefore, accurate measurement of GFR is clinically important. Among the factors that affect the GFR result, there have been many discussions on the methods such as the correction of the kidney depth, net syringe count, and the method of setting the ROI. However there has been no consideration of counting in the most basic factors like height and weight measurement. In this study, we investigate how height and weight changes affects the result of GFR and review the importance of standardized body measurements. Materials and Methods Fifty patients who underwent GFR test were randomly sampled and examined for changes in height and body weight within one month. From the normal patients without renal disease to the patients with severely decreased GFR, we applied the GFR formula of Gate with varying height and weight. Results: The result showed variation of the height at maximum three centimeters and six kilograms of weight. The first calculation of GFR was done with fixed height value and control variable as weight. Weight was incremented by one kilogram each time up to six kilograms. The GFR showed increased result with increasing weight. The result of GFR showed ten percent increase with six kilograms of weight increase. On the other hand, when height value was incremented by one centimeter up to three centimeters showed decreased GFR result with fixed weight value. Up to three centimeters of height increase showed two percent of decreased GFR with fixed weight. Conclusion This study showed varying GFR result when height and weight changes. Therefore it is clinically crucial not only to maintain and manage body measuring instrument but also to have a standardized measurement methods to derive accurate measured values and to achieve reproducibility.

The Effects of Neuro-feedback Training on Self-regulation of Acquired Factors and Height Growth (뉴로피드백 훈련이 후천적 요인의 자기조절력과 키 성장에 미치는 영향)

  • MINGYANG, QU;Lee, Ji-An
    • Journal of Convergence for Information Technology
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    • v.8 no.6
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    • pp.15-20
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    • 2018
  • This study aimed to find an effective intervention measure through establishing the correlation between self-regulation (control over life style) and height growth through neuro-feedback training. 40 elementary students in grades two to four with height growth programs (20 experimental group students, 20 control group students) were examined for the changes before and after undergoing neuro-feedback training. The experiment lasted for three months with one 30-minute training session two times a week. After analyzing the differences in self-regulation among the control group with no neuro-feedback training and the experimental group with neuro-feedback training, the differences in height growth were analyzed. First of all, there were positive changes in self-regulation of the experimental group compared with the control group. Secondly, the experimental group showed larger changes in height growth. In conclusion, neuro-feedback training had positive effects upon the self-regulation that adjusts the acquired factors of height growth, which led to positive effects.