• Title/Summary/Keyword: variability(deviation)

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An Uncertainty Assessment of AOGCM and Future Projection over East Asia (동아시아 지역의 AOGCM 불확실성 평가 및 미래기후전망)

  • Kim, Min-Ji;Shin, Jin-Ho;Lee, Hyo-Shin;Kwon, Won-Tae
    • Atmosphere
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    • v.18 no.4
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    • pp.507-524
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    • 2008
  • In this paper, future climate changes over East Asia($20^{\circ}{\sim}50^{\circ}N$, $100^{\circ}{\sim}150^{\circ}E$) are projected by anthropogenic forcing of greenhouse gases and aerosols using coupled atmosphere-ocean general circulation model (AOGCM) simulations based on Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) B1, A1B and A2 scenarios. Before projection future climate, model performance is assessed by the $20^{th}$ Century (20C3M) experiment with bias, root Mean Square Error (RMSE), ratio of standard deviation, Taylor diagram analysis. The result of examination of the seasonal uncertainty of T2m and PCP shows that cold bias, lowered than that of observation, of T2m and wet bias, larger than that of observation, of PCP are found over East Asia. The largest wet bias is found in winter and the largest cold bias is found in summer. The RMSE of temperature in the annual mean increases and this trend happens in winter, too. That is, higher resolution model shows generally better performances in simulation T2m and PCP. Based on IPCC SRES scenarios, East Asia will experience warmer and wetter climate in the coming $21^{st}$ century. It is predict the T2m increase in East Asia is larger than global mean temperature. As the latitude goes high, the warming over the continents of East Asia showed much more increase than that over the ocean. An enhanced land-sea contrast is proposed as a possible mechanism of the intensified Asian summer monsoon. But, the inter-model variability in PCP changes is large.

A Preliminary Study on UAV Photogrammetry for the Hyanho Coast Near the Military Reservation Zone, Eastern Coast of Korea (동해안 군사시설보호구역 주변 향호 연안역을 대상으로 무인항공사진측량에 관한 예비 연구)

  • Kim, Baeck-Oon;Yun, Kong-Hyun;Chang, Tae-Soo;Bahk, Jang-Jun;Kim, Seong-Pil
    • Ocean and Polar Research
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    • v.39 no.2
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    • pp.159-168
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    • 2017
  • To evaluate the accuracy of UAV photogrammetry for Hyangho coast, eastern coast of Korea, we conducted a field experiment wherein UAV photogrammetry test was repeated three times. Since the Haygho coast is located within a military reservation zone, it was necessary to obtain permission to gain access to the beach and to have sensitive aerial photographs showing military facilities inspected and cropped. The standard deviation of the UAV shooting position between the three tests was less than 1 m, but repeatability of footprint on the ground was low due to wind-driven variability of the UAV pose. Self-calibrating bundle adjustment(SCBA) of implementing non-metric camera calibration was failed in one test. In two tests, the vertical error was twice as large as the pixel size except for those areas that were subject to security inspection and cropping. Given the problems that can arise with regard to the repeatability of the shooting area as well as the possibility of failure with regard to SCBA, we strongly recommend that UAV photogrammetry in coastal areas needs to be repeated at least twice.

Effects of Structural Parameter Variations on Dynamic Responses (해석(解析)모델의 구조변수(構造變數) 변동(變動)이 동적응답에 미치는 영향(影響))

  • Park, Hyung Ghee;Lim, Boo Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.3
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    • pp.59-67
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    • 1993
  • The variations of the natural frequencies and the peak response acceleration at the top of prestressed concrete reactor building due to random variability and/or model uncertainty of structural parameters are studied. The results may be used as essential input parameters in seismic probabilistic risk assessment or seismic margin assessment of the reactor building. The sensitivity test of each structural parameter is first performed to determine the most influential parameter upon the natural frequency of structure model. Then Monte Carlo simulation technique is applied to evaluate the effect of parameter variation on the natural frequencies and the peak response acceleration. The acceleration time history is obtained by direct integration scheme. As the study results, it is found that the fundamental natural frequency and the peak response acceleration at the top of the building are most strongly affected by Young's modulus among the structural parameters, in which the value of mean plus one standard deviation obtained by probabilistic approach deviates up to about (+)12% from the result of deterministic method. Considering the uncertainty of flexural rigidity, the structural responses vary in range of (-)4%~(+)14%.

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Influence of Fertilizing Methane Fermentation Digested Sludge to Rice Paddy on Growth of Rice and Rice Taste (메탄발효 소화액 시용이 벼 생육과 식미에 미치는 영향)

  • Ryu, Chan-Seok;Lee, Choung-Keun;Umeda, Mikio;Lee, Seung-Kyu
    • Journal of Biosystems Engineering
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    • v.34 no.4
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    • pp.269-277
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    • 2009
  • In this research, the vegetation growth and rice taste of the liquid fertilizer applied fields (LF) were compared with those of chemical fertilizer applied fields(CF) in order to confirm the possibility of methane fermentation digested sludge as liquid fertilizer using precision agriculture and remote sensing technology. In panicle initiation stage, the vegetation growth at LF was 60%~80% of it at CF and there were significant difference of nitrogen contents between CF and LF. The estimation model of nitrogen contents was established by GNDVI (R=0.607, RMSE=$1.04\;g/m^2$, n=36, p<0.01). In heading stage, vegetation growth at LF went close to it at CF as ratio of 80%~95%. The nitrogen content estimation model was also established (R=0.650, RMSE=$1.73\;g/m^2$, n=35, p<0.01) and there were significant difference of spatial variability between LF and CF. There were not significant difference of rice taste and it's elements, when three samples, which were more than twice of standard deviation, were excepted. The protein contents estimation model using GNDVI of before harvesting (R=0.700, RMSE=0.470%, n=29, p<0.01) were more suitable to predict the protein contents at harvesting comparing with it of heading stage(R=0.610, RMSE=0.521%, n=29, p<0.01).

Development of Electrogastrography System (위전도 계측시스템의 개발)

  • Han, W.T.;Kim, I.Y.;Kim, W.K.;Park, K.W.;Kim, Hui-Chan;Son, J.I.;Rhee, P.L.;Rhee, J.C.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.403-406
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    • 1997
  • Electrogastrogaphy(EGG) is the technique by which gastric myoelectrical activity is recorded noninvasively, from electrodes on the abdominal skin. Despite many attempts made over the decades, the clinical application of the EGG signal has not improved to the identification of waveform characteristics using comparison of EGG signal to be detected other EGG system. Cutaneous measurements of EGG are yet to be standardized in methods of detection and analysis. This may be responsible in part for some of the variability in the results. Thus, we develope EGG system composed of amplifiers, analysis methods, patient database or standardization. we introduce configurations of EGG system and their functions. Several important EGG parameters are introduced, including the dominant frequency and power of the EGG, the relative, period EGG-dominant frequency and power, the instability coefficient of EGG-dominant frequency and power, standard deviation, the percentage of running spectrum activity of gastric slow waves.

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Determination of In-Vivo Glenohumeral Translation During Loaded and Unloaded Arm Elevation

  • Nishinaka, Naoya;Mihara, Kenichi;Suzuki, Kazuhide;Makiuchi, Daisuke;Matsuhisa, Takayuki;Tsutsui, Hiroaki;Kon, Yoshiaki;Banks, Scott A.
    • The Academic Congress of Korean Shoulder and Elbow Society
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    • 2009.03a
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    • pp.44-44
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    • 2009
  • The purpose of this study was to investigate humeral translation relative to the glenoid invivo during loaded and unloaded shoulder abduction. CT scans of 9 healthy shoulders were acquired and 3D models were created. The subject was positioned in front of a fluoroscope and motions were recorded during active abduction. The subjects performed two trials of holding a 3kg weight and unload. 3D motions were determined using model-based 3D-to-2D registration to obtain 6 degrees of freedom kinematics. Glenohumeral translation was determined by finding the location on the humeral head with the smallest separation from the glenoid. Humeral translation was referenced to the glenoid center in the superior/inferior direction. The humerus moved an average of 2 mm, from inferior to central on the glenoid, during arm abduction for both conditions. The humeral head was centered within 1mm from the glenoid center above $70^{\circ}$. There were no statistically significant differences for both conditions. The standard deviation decreased gradually over the motion, with significantly lower variability at the end of abduction compared to the initial unloaded position. We assumed that the humeral translation to the center of the glenoid provides maximum joint congruency for optimal shoulder function and joint longevity. We believe this information will lead to better strategies to prevent shoulder injuries, enhance rehabilitation, and improve surgical treatments.

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Interannual Variability of Sea Water Temperatures in the Southern Waters of the Korean East Sea (한국 동남해역의 장주기 수온변동)

  • Ro, Young Jae
    • 한국해양학회지
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    • v.24 no.1
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    • pp.1-14
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    • 1989
  • This study analyzes the interannual periodicity by using the statistical techniques of probability, spectral analysis, empirical orthogonal function analysis (EOF), and coherency analysis. The data base for this study is the time series of 1971-1985 temperature, salinity in the southern waters of the East Sea, 1960-1986 mean sea level at Pusan and Izuhara, and 1960-1986 sea level atmospheric pressure at Pusan. The appearances of anomalous temperatures higher and lower than 15-year mean monthly average with one standard deviation are about 30% of total data. The significant interannual period for temperature, salinity and sea level fluctuation is 36.6, and 23.3 months. The empirical orthogonal function analyses show that the 1st mode of the EOFs is responsible for more than 90% of total variance of the surface temperature variations, while in near-bottom waters, the relative importance of the higher EOF modes is much greater explaining more than 30% of total variance. The coherency between normalized temperatures and salinities is significant at the interannual period of 36.6 and 21.3 months.

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Physiological and Ecological Response of Agronomic Characters Related to Source and Sink in Rice (벼의 Source와 Sink 관련형질의 생리생태적 반응)

  • 최수일
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.3
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    • pp.239-245
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    • 1989
  • This experiment was conducted to study the physiological and ecological responses of agronomic characters related to source and sink relation in rice. Standard deviation and coefficient of variability of agronomic characters by individual tiller were greatly influenced by the lower internodes in the length of internode, flag leaf in the leaf blade, lower leaf blade in the leaf width, and the number and spikelets of secondary rachis branch in panicle. In relation to the parts of source and sink of rice plant and the number of spikelet in panicle, the number of spikelet was significantly correlated with the length and leaf area of second leaf blade, the length of second internode, and culm diameter of third internode. The correlation of the length of panicle with the length of internode and leaf blade was greatly influenced by the length of second leaf blade and second internode. The number of spikelet was increased with increasing the second rachis branch rather than first rachis branch. The content of total inorganic nutrients was greatest at leaf blade followed by leaf sheath and internode, and panicle.

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Relationship between Vestibuloocular Reflex and Autonomic Nerve Response in Adults (성인에서 전정안구반사를 이용한 평형감각과 자율신경반응의 관련성)

  • 김규겸;박현영;전희정;윤상대;박병림
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1999.03a
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    • pp.237-242
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    • 1999
  • The nature of the interactions between the vestibular and autonomic systems is complex and has not been fully defined. Vestibuloocular reflex induced by sinusoidal rotation and activity of the autonomic nerves in the heart were measured to investigate the interactions between the vestibular system and the autonomic nervous system in healthy adults. Eye movement induced by sinusoidal rotation of the whole body or optokinetic stimulation at 0.04 Hz was analyzed in gain, phase, and symmetry. EKG was measured during vestibular stimulation and analyzed in heart rate variability including mean R-R interval, standard deviation (SD) and coefficient of variance (CV) of R-R interval, and power spectrum of low frequency region (LF) and high frequency region (HF). Gain of eye movement was 0.65${\pm}$0.03 by ratatory stimulation, 0.70${\pm}$0.02 in optokinetic stimulation, 0.08${\pm}$0.02 in visual suppression, and 0.84${\pm}$0.04 in visual enhancement. In R-R interval, resting condition (control) was 0.82${\pm}$0.03 sec, and visual suppression showed significant increase and visual enhancement did significant decrease compared with control (p<0.01).CV was 0.06${\pm}$0.02 in control and visual enhancement increased significantly (p<0.05). In LF/HF control was 1.40${\pm}$0.23, which was not different from rotatory or optokinetic stimulation. But visual suppression decreased LF/HF significantly and visual enhancement increased significantly compared with control (p<0.01). These results suggest that degree of gain corresponds with LF/HF and increased gain in visual enhancement is deeply related to the activity of sympathetic nerves.

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Study of protein loop conformational changes by free energy estimation using colony energy

  • Kang, Beom Chang;Lee, Gyu Rie;Seok, Chaok
    • Proceeding of EDISON Challenge
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    • 2014.03a
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    • pp.63-74
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    • 2014
  • Predicting protein loop structures is an important modeling problem since protein loops are often involved in diverse biological functions by participating in enzyme active sites, ligand binding sites, etc. However, loop structure prediction is difficult even when structures of homologous proteins are known due to large sequence and structure variability among loops of homologous proteins. Therefore, an ab initio approach is necessary to solve loop modeling problems. One of the difficulties in the development of ab initio loop modeling method is to derive an accurate scoring function that closely approximates the true free energy function. In particular, entropy as well as energy contribution have to be considered adequately for loops because loops tend to be flexible compared to other parts of protein. In this study, the contribution of conformational entropy is considered in scoring loop conformations by employing "colony energy" which was previously proposed to estimate the free energy for an ensemble of conformations. Loop conformations were generated by using two EDISON_Chem programs GalaxyFill and GalaxySC, and colony energy was designed for this sampling by tuning relevant parameters. On a test set of 40 loops, the accuracy of predicted loop structure improved on average by scoring with the colony energy compared to scoring by energy alone. In addition, high correlation between colony energy and deviation from the native structure suggested that more extensive sampling can further improve the prediction accuracy. In another test on 6 ligand-binding loops that show conformational changes by ligand binding, both ligand-free and ligand-bound states could be identified by using colony energy when no information on the ligand-bound conformation is used.

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