• The korean journal of orthodontics
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• v.37 no.1 s.120
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• pp.16-28
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• 2007

Objective: Evaluation of individual growth is important in orthodontics. The aim of this study was to develop a convenient software that can evaluate current growth status and predict further growth. Methods: Stature data of 2 to 20 year-old Koreans (4893 boys and 4987 girls) were extracted from a nationwide data. Age-sex-specific continuous functions describing percentile growth curves were constructed using natural cubic spline function (NCSF). Then, final stature prediction algorithm was developed and its validity was tested using longitudinal series of stature measurements on randomly selected 200 samples. Various accuracy measurements and analyses of errors between observed and predicted stature using NCSF growth curves were performed. Results: NCSF growth curves were shown to be excellent models in describing reference percentile stature growth curie over age. The prediction accuracy compared favorably with previous prediction models, even more accurate. The current prediction models gave more accurate results in girls than boys. Although the prediction accuracy was high, the error pattern of the validation data showed that in most cases, there were a lot of residuals with the same sign, suggestive of autocorrelation among them. Conclusion: More sophisticated growth prediction algorithm is warranted to enhance a more appropriate goodness of model fit for individual growth.

• Journal of Korea Water Resources Association
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• v.47 no.1
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• pp.25-35
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• 2014

The objective of this study is to evaluate TOPLATS land surface model performance through comparison of results of water and energy balance analysis. The study area is selected Nakdong river basin and high resolution hydrometeorological components of which spatio-temporal resolution is 1 hr and 1 km are simulated during 2003 to 2013. The simulated daily and monthly depth of flows are well fitted with the observed one on Andong and Hapcheon dam basin. In results of diurnally analysis of energy components, change pattern throughout the day of net radiation, latent heat, sensible heat, and ground heat under energy balance analysis have higher accuracy than ones under water balance analysis at C3 and C4 sites. Especially, root mean square errors of net radiation and latent heat at C4 site are shown very low as 22.18 $W/m^2$ and 7.27 $W/m^2$, respectively. Mean soil moisture and evapotranspiration in summer and winter are simulated as 36.80%, 33.08% and 222.40 mm, 59.95 mm, respectively. From this result, when we need high resolution hydrometeorological components, energy balance analysis is more reasonable than water balance analysis. And this results will be used for monitor and forecast of weather disaster like flood and draught using spatial hydrometeorological information.

• The Journal of the Acoustical Society of Korea
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• v.22 no.7
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• pp.519-527
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• 2003

Speech is much influenced by the existence of outliers which are introduced by such an unexpected happenings as additive background noise, change of speaker's utterance pattern and voice detection errors. These kinds of outliers may result in severe degradation of speaker recognition performance. In this paper, we proposed the GMM based on robust principal component analysis (RPCA-GMM) using M-estimation to solve the problems of both ouliers and high dimensionality of training feature vectors in speaker identification. Firstly, a new feature vector with reduced dimension is obtained by robust PCA obtained from M-estimation. The robust PCA transforms the original dimensional feature vector onto the reduced dimensional linear subspace that is spanned by the leading eigenvectors of the covariance matrix of feature vector. Secondly, the GMM with diagonal covariance matrix is obtained from these transformed feature vectors. We peformed speaker identification experiments to show the effectiveness of the proposed method. We compared the proposed method (RPCA-GMM) with transformed feature vectors to the PCA and the conventional GMM with diagonal matrix. Whenever the portion of outliers increases by every 2%, the proposed method maintains almost same speaker identification rate with 0.03% of little degradation, while the conventional GMM and the PCA shows much degradation of that by 0.65% and 0.55%, respectively This means that our method is more robust to the existence of outlier.

• Applied Microscopy
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• v.42 no.1
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• pp.1-7
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• 2012

The possibility of nanoparticles (NPs) in biotechnology had been discussed by biomedical investigators. Here we report to suggest a solution and problems when using electron microscopy to determine the distribution of quantum dots (QDs) nanoparticles that penetrate skin. The results of this study showed that NPs were able to penetrate stratum corneum (SC) and sebocyte via hair follicle. However, we have found artifacts such as nanoparticles that are produced from combination of free fatty acid and osmium tetroxide during specimen preparation. It is usually difficult to identify NPs. Therefore, we tried to resolve these problems by comparing the cross-correlation image pattern that are derived from the images of sample that had been processed differently. This method can contribute to more accurate interpretation and minimal errors during the analysis using quantum dot as tracer.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.361-370
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• 2004

The purpose of this study was to evaluate the outcome and Factors that influence the quantity of Phoria in the low correction and perfect correction. Also the coincidence with the opticenter and the pupillary distance was a principal factor that influence the quantity of Phoria. Thereupon, this study is attributed to promote the perfect Phoria test. The subjects for this study were 120 persons(240 eye) in myopic refractive errors. ISP/WIN program was used for the data analysis. The collected data was analyzed by descriptive statistics and Spearman's correlation coefficient. The results of this study were as follows: 1. The prism pattern was difference between low correction and perfect correction in the Phoria test. The proportion of orthophoria was changed from 10.0% to 12.5%, exophoria was changed from 67.5% to 62.5%, and esophoria was changed from 22.0% to 32.5%, respectively. 2. The average of optical center distance and pupillary distance were 31.70mm and 31.49 mm, respectively. 3. Among the 120 myopic glasses wearers, the distance between optical centers was coincided with the pupillary distance in 37.5%, and discrepant in 62.5%. 4. For the patients who were coincided with the pupillary distance, the proportion of exophoria decreased 53.33%, esophoria increased 20.0%. 5. For the changing of the quantity of Phoria in the low correction, the degree of exophoria decreased 1.11 prism diopters in the perfect correction, esophoria increased 0.39 prism diopters.

• Fire Science and Engineering
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• v.15 no.1
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• pp.127-138
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• 2001

I. introduction. A government goal at the present is established to make a welfare nation and to keep people's safe living, but it is criticised that when a large-scale disaster happens, the authority concerned could not deal with it, causing many people injured and material damage. Moreover, in these days, cities have many risk factors. extremely large and intelligent building, industrial facilities and underground equipment have many risk themselves along with scientific progress. The cope with disaster effectively, government must have efficient organization, skillful personnel, tool, facilities and so on. To reduce the damages, what's the most effective government organization\ulcorner II. Government organization for managing disaster In a few decades, a large-sized accidents broke out in korea, for example, collapse of Sampoong department store, break of Sungso bridge, explosion of Daegu city gas, gas explosion accident at Ahyon-dong etc. but government has not any adequate disaster response organization. Especially, after collapse of Sampoong department store broke out, Disaster Management Act is enacted to solve the past problem. According to Disaster management Act, disaster is limited in manmaid disaster. Therefore, in this thesis, disaster management is inspected theoretically, organization of disaster management for pattern of disaster, and role, duty of government organization, emergency relief organization system and actual conditions are analyzed. there are some problems. there are trials and errors. the government has changed the disaster management organization by the disaster management law. the organization consists of central and local government. but both of government do not work together harmoniously. in thesis, I would like to introduce the advanced nations disaster management organization, and study our central, local government organization. III. Conclusion Change and development of the government disaster management organization is the goal of this thesis. we have to increase public service in response and manage disaster. protecting civilian's life from the disaster is very important responsibility of government. there would be better way of government disaster management organization.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.71-84
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• 2017

Radon, which enters the interior environment from soil, rocks, and groundwater, is a radioactive gas that poses a serious risk to humans. Indoor radon concentrations are measured to investigate the risk of radon gas exposure and reliable radon concentration mapping is then performed for further analysis. In this study, we compared the predictive performance of various univariate kriging algorithms, including ordinary kriging and three nonlinear transform-based kriging algorithms (log-normal, multi-Gaussian, and indicator kriging), for mapping radon concentrations with an asymmetric distribution. To compare and analyze the predictive performance, we carried out jackknife-based validation and analyzed the errors according to the differences in the data intervals and sampling densities. From a case study in South Korea, the overall nonlinear transform-based kriging algorithms showed better predictive performance than ordinary kriging. Among the nonlinear transform-based kriging algorithms, log-normal kriging had the best performance, followed by multi-Gaussian kriging. Ordinary kriging was the best for predicting high values within the spatial pattern. The results from this study are expected to be useful in the selection of kriging algorithms for the spatial prediction of data with an asymmetric distribution.

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.62-65
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• 2010

This study was carried out to estimate the size and exine pattern of pollen grains in seven species of the genus Lilium by using scanning electron microscope. Exine of pollen grains, which were all monad, took the prolate forms with a pollen aperture. However, there were various L/W ratio between length (L) and width (W) of pollen grains among selected Lilium species. The pollen of L. distichum was oblong shape which had the highest L/W ratio of 2.59. On the other hand, that of L. concolor var. partheneion was broadly elliptical shape close to circle which had the lowest L/W ratio of 1.82. The surface patterns of exine were reticulate in all Lilium species that have showed diverse forms in their lumina. Pollen length and width in L. lancifolium had the greatest value, 115.90 and $46.54{\mu}m$, respectively, in comparison with those of L. tsingtauense, 70.33 and $38.72{\mu}m$, respectively. Except L. distichum and L. leichtlinii var. maximowiczii which had a similar pollen length within standard errors, the others in Lilium species showed different sizes, respectively. Therefore, these results indicated that pollen length could be a better standard for the classification of Lilium species than exine surface patterns or pollen dissection area.

• Korean Journal of Optics and Photonics
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• v.24 no.5
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• pp.213-216
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• 2013

This paper presents a combination of linear Fresnel lenses optimized for ${\times}25$ solar concentration. The combined lens consists of $5{\times}5$ linear Fresnel lenses. Each Fresnel lens is of $10{\times}10$ mm and optimized to tilt the incoming light onto a solar cell of the same size. All of the optimized Fresnel segments have the same pattern height of 35 ${\mu}m$, draft angle of $4^{\circ}$, and edge groove round of 1 ${\mu}m$ but with different facet angles varying from $14.1^{\circ}$ to $31.2^{\circ}$. The solar concentrating efficiency of the combination is shown to be over 80% and more robust than a conventional single ${\times}25$ circular Fresnel lens in terms of pointing misalignment and manufacturing errors. A sensitivity analysis finds that the edge groove round should be kept as small as machining allows since the concentrating efficiency drops ~5% per 1 ${\mu}m$ increase of the edge groove.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.366-375
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• 2022

The monitoring of electricity consumption using Internet of Things (IoT) technology is attracting attention as a technology to reduce operation costs of smart farms. In this study, we propose a method to apply a real-time electrical consumption monitoring system (the e-Gauge system) and utilization of the collected data real-time while a melon-producing smart farm is in operation. For this purpose, the electrical consumption data for the individual smart-farm facilities such as boilers, nutrient distribution systems, automatic controllers, circulation fans, boiler controllers, and other IoT-related utilities were collected during three months of melon cultivation period. By using the monitoring results, the electrical energy consumption pattern was analyzed as an example, and necessary considerations needed to optimally utilize the measurement data were suggested. This paper will be useful in lowering the technological implementation barriers for new researchers to build a electrical consumption monitoring system and reducing trial and errors in the usage of the generated data.