• The Journal of the Korean dental association
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• v.51 no.6
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• pp.346-354
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• 2013

Early identification of maxillary canine impaction is very important, because of treatment duration time. Analysis used by 3-dimensional computed tomography is more important than before in treatment planning. The aim of this study was to analysis of factors associated with the treatment during time of forced eruption of the impacted maxillary canine using 3-dimensional computed tomography. 17 patients were analysed in Daejeon dental hospital of Wonkwang university(16 patients with unilateral impactions and 1 patient with bilateral impaction). In total, 18 maxillary impacted cannines were analysed by 3-dimensional computed tomography. The results obtained were as follow; 1. There was positive correlation between the age of patient and treatment duration time. 2. There was positive correlation between the distance of occlusal plane to cusp of maxillary impacted canine and treatment duration time, and negative correlation between the length of maxillary impacted canine and treatment duration time. 3. There was positive correlation between the angulation of midsagittal plane to axis of maxillary impacted canine and treatment duration time, and negative correlation between occlusal plane to axis of maxillary impacted canine and treatment duration time. In conclusion, age, tooth length, distance from the canine cusp tip to the occlusal plane, angulation of tooth axis to occlusal plane and midsagittal plane allow that we can predict treatment duration time.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.383-394
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• 2008

We examine geoeffective directional parameters of coronal mass ejections (CMEs). We select 30 front-side halo CMEs from SOHO LASCO CMEs whose speed is larger than 1000km/s and longitude is less than ${\pm}30^{\circ}$. These are thought to be the most plausible candidate of geoeffective CMEs. We examine the relation between CMEs directional parameters (Earthward direction, eccentricity, ${\Delta}$ distance and central angle parameter) and the minimum value of the Dst index. We have found that the Earthward direction parameter has a good correlation with the Dst index, the eccentricity parameter has a much better correlation with the Dst index. The bo distance and central angle parameter has a poor correlation with the Dst index. It's, however, well correlated with the Dst index in very strong geomagnetic storms. Most of CMEs causing very strong storms (Dst ${\leq}$-200nT) are found to have large Earthward direction parameter $({\geq}0.6)$, small eccentricity, bo distance and central angle parameters $(E{\leq}0.4,\;{\Delta}X\;and\;sin\;{\theta}{\leq}0.2)$. These directional parameters are very important parameters that control the geoeffectiveness of very fast front-side halo CMEs.

• Physical Therapy Korea
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• v.11 no.2
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• pp.35-45
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• 2004

The purpose of this study was to investigate the correlation and characteristics between electromyographic (EMG) activities of lower leg muscles and the posturographic assessment of static balance control in normal adults. Twenty-four young, healthy adults(12 males, 12 females) participated in the study. Center of pressure (COP) parameters were obtained using force platform as total path distance, total sway area, X mean frequency and Y mean frequency for 20 seconds in the following conditions: (1) comfortable standing with eyes opened or closed, (2) uncomfortable standing (feet together) with eyes opened or closed, (3) virtual moving surround delivered using Head mount display (HMD) with four different moving patterns. The virtual moving patterns consisted of close-far, superior-inferior tilting (pitch), right-left tilting (roll), and horizontal rotation (yaw) movements. Surface electromyographic activites were recorded on the tibialis anterior, peroneus longus, medial and lateral heads of gastrocnemius muscles under each condition. Correlation between the posturographic measures and EMG activities were evaluated. Total path distance and total sway area of COP were significantly increased during uncomfortable standing. EMG activity of tibialis anterior was significantly more during uncomfortable standing and virtual moving surround stimulation than during comfortable standing. Total path distance and sway area of COP during comfortable standing with closed eyes showed significant positive correlation with the EMG activities of the lateral head of gastrocnemius muscle. Total path distances and total sway area of COP during muscle. Total path distances and total sway area of COP during presentation of virtual moving surround also had significant positive correlations with EMG activities of the lateral head of gastrocnemius muscle under close-far movement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1276-1284
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• 2017

Lightweight Encryption Algorithm (LEA) that was standardized as a lightweight block cipher was implemented with 8-bit data path, and the vulnerability of LEA encryption processor to correlation power analysis (CPA) attack was analyzed. The CPA used in this paper detects correct round keys by analyzing correlation coefficient between the Hamming distance of the computed data by applying hypothesized keys and the power dissipated in LEA crypto-processor. As a result of CPA attack, correct round keys were detected, which have maximum correlation coefficients of 0.6937, 0.5507, and this experimental result shows that block cipher LEA is vulnerable to power analysis attacks. A masking method based on TRNG was proposed as a countermeasure to CPA attack. By applying masking method that adds random values obtained from TRNG to the intermediate data of encryption, incorrect round keys having maximum correlation coefficients of 0.1293, 0.1190 were analyzed. It means that the proposed masking method is an effective countermeasure to CPA attack.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.302-305
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• 2008

For an complete image composition to be stitched on several mosaic images, tracing displacement of direction and distance between successive images are important parameters. The input image is modeled by using a general second order two-dimensional Taylor-series and then converting it to a $3{\times}3$ correlation block and storing the data. A moving factor and coordinate is calculated by comparing the continuous correlation blocks. The experimentation result has a success rate of 85% for moving path tracing as continuous images are moved to 10% of image central position.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.179-187
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• 2010

Miniature spectrometers can be applied for various purposes in wide areas. This paper shows how a wellmade spectrometer on-a-chip of a low performance and low-cost filter-array can be used for recognizing types of red wine. Light spectra are processed through a filter-array of a spectrometer after they have passed through the wine in the cuvettes. Without recovering the original target spectrum, pattern recognition methods are introduced to detect the types of wine. A wavelength cross-correlation turns out to be a good distance metric among spectra because it captures their simultaneous movements and it is affine invariant. Consequently, a well-designed spectrometer is reliability in terms of its repeatability.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1046-1050
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• 2004

Six physical properties (enthalpy, density, decomposition temperature, solubility in water, pKa values, and hydronium potential) were examined by molecular modeling techniques. The molecular connectivity index, Wiener distance index, and Ad hoc descriptor are employed as structural parameters to encode information about branching, size, cyclization, unsaturation, heteroatom content, and polarizability. This paper examines the correlation of the molecular modeling techniques parameters and the physicochemical properties of amino acids. As a results, calculated values were in agreement with experimental data in the above six physical properties of amino acids and the molecular connectivity index was superior to the other indices in fitting the calculated data.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.4
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• pp.247-253
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• 2006

Power consumption for double-stage paddle impeller in spherical and cylindrical agitated vessel was measured over a wide range of Reynolds number from laminar to turbulent flow regions. The power correlation was obtained which was applied to both spherical and cylindrical vessel, when the apparent diameter of the spherical vessel was equal to the diameter of the cylindrical vessel which had a height equal to its diameter and had the same volume as the spherical vessel. The power consumption for the double-stage impeller was dependent upon the distance of among the impeller in the agitated vessels, as follows: $$f/2={\frac{C_L}{Re_G}}+{\frac{Ct}{2}}({\frac{C_tr}{Re_g}}+Re_g)^{-m}$$

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.622-625
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• 2004

The CMP monitoring system was newly developed by the aid of friction force measurement, resulting from installation of piezoelectric quartz sensor on R&D polisher. The correlation between friction and CMP results was investigated in terms of tribological aspects by using the monitoring system. Various friction signals were monitored and analyzed by the change of experimental conditions such as pressure, velocity, pad and slurry. First of all, the lubrication regimes were classified with Sommerfeld Number through measuring coefficient of friction in ILD CMP. And then, the removal mechanism of abrasives could be understood through the correlation with removal rate and coefficient of friction. Especially, the amount of material removal per unit sliding distance is directly proportional to the friction force. The uniformity of CMP performances was also deteriorated as coefficient of friction increased.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1689-1694
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• 2005

Face detection plays an important role in face recognition, video surveillance, and human computer interface. In this paper, we present a face detection system using eye detection with progressive thresholding from a digital camera. The face candidate is detected by using skin color segmentation in the YCbCr color space. The face candidates are verified by detecting the eyes that is located by iterative thresholding and correlation coefficients. Preprocessing includes histogram equalization, log transformation, and gray-scale morphology for the emphasized eyes image. The distance of the eye candidate points generated by the progressive increasing threshold value is employed to extract the facial region. The process of the face detection is repeated by using the increasing threshold value. Experimental results show that more enhanced face detection in real time.