• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.39-49
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• 1999

Monolayer thick fluorocarbon films were characterized by the contact angle measurements. The contact angles of three different liquids, water, formamide and diiodomethane were measured on spun coated, vapor phased deposited films and Teflon surface. The highest contact angle over $130^{\circ}$was observed on fluorocarbon films deposited on Al substrates while the lowest angles below $70^{\circ}$deposited on oxide. The surface energies were calculated based on Lewis acid /base theory. The surface energies of Teflon and spin coated FC films were calculated to have 18 and 8.4 dynes /cm, respectively. Higher energies of 31 to .35 dynes /cm were calculated on vapor phase deposited films on silicon and oxide. However vapor phase deposited films on aluminum only showed a large Lewis base energy term. It might be explained by the surface roughness and heterogeneity as observed by dynamic contact angles and AFM measurements.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.565-606
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• 1993

The purpose of this study was to evaluate the change of before and after treatment of anterior openbite malocclusions treated by Multiloop Edgewise Archwire technique. The openbite sample consisted of 4 male and 12 female adults, treated with nonextraction or third molar extraction. The normal sample consisted of 58 subjects, which have pleasing facial profile and normal occlusion and no experience of orthodontic or prosthodontic treatment. The 58 subjects of normal sample were subdivided by cephalemetric vertical relationship of face. The 40 subjects, cephalometric vertical relationship of face was in normal range, classified as Normal Sample group 1. The 18 subjects, increased cephalometric vertical relationship of face, classified as Normal Sample group 2. The computerized cephalometric analysis was accomplished with 50 reference points for 22 skeletal measurements, 46 dentoalveolar measurements, 8 soft tissue measurements. Statistical analysis of the data was carried out with paired t-test, Student's t-test, and DUNCAN test using SAS(PC version), The results were as follows : 1. There were no statistically significant differences in skeletal measurement between before and after treatment. The major changes were in dentoalveolar region. 2. After treatment, the long axis of maxillary and mandibular posterior teeth were distally tipped-back, and uprighted to bisected occlusal plane. The interincisal angle was increased. 3. There were no statistically significant increase in the upper posterior dental height and statistically significant decrease in the lower posterior dental height. The upper anterior dental height was increased, but there was no statistically significant increase in the absolute upper anterior dental hight. The lower anterior dental height was increased. 4. After treatment, the maxillary occlusal plane to palatal plane angle and the mandibular occlusal plane to mandibular plane angle were statistically significant increased. Then, there were no statistically significant difference between after treatment group and normal sample group 2. 5. After treatment, the percentage of upper lip length to upper anterior dental height was decreased. Then, There were no statistically significant difference between after treatment group and normal sample group 2.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.479-482
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• 2004

We report a method for simultaneous measurements of cell gap, twist angle, birefringence dispersion of liquid crystal (LC) material and alignment directions in filled reflective LC cells. The method is based on spectral measurements of the LC cell reflectivity for three orientations ($0^{\circ},45^{\circ},90^{\circ}$) of the exit polarizer and may be applied for LC cells with low and high gaps.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.21-24
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• 2002

Many methods are available to measure leaf area index(LAI) directly and are variations of either Leaf area index(LAI) and leaf angle distribution are widely used indices of canopy structure that are difficult to measure directly. Direct measurements of canopy structure are tedious and labor intensive in small canopies and nearly impossible in large forest canopies. This study introduced fundamental theories in LAI measurements and applied that for several crops.

• Journal of Fashion Business
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• v.6 no.6
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• pp.34-42
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• 2002

Anthropometric studies and multicultural research on body changes are fundamental and important data for domestic apparel industry and for globalization of women's clothing marketing. The objective of this study is to compare the general body measurements and shoulder angles of Korean and U. S. elderly women to supply basic data for the apparel design. The anthropometric data was collected including both direct and indirect measurements of 272 women over the age of 55 in Korean (subject = 123) and the U.S (subject = 149). The statistical methods used for the analysis of measurement data are the factor and cluster analysis respectively. The results of the factor analysis indicated that 5 factors can be extracted in Korean and 4 factors can be extracted in the U. S. from 15 body measurements to explain the variance. The results of cluster analysis by shoulder slope angle and forward displacement of the shoulder of Korean and the U. S. women classified them in three groups, cluster 1, cluster 2 and cluster 3 respectively.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.1
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• pp.36-40
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• 2010

In this paper, the well-known LOB-based emitter localization using linear LSE algorithm is numerically implemented and the heuristic guidelines for the parameter values to achieve 1% RMS error are presented. In the simulation, we changed the total observation durations for LOB measurements, time interval between successive LOB measurements and sensor trajectories. The effects of the time interval of LOB measurements, the time duration of the LOB measurements and the angle of flight path arc on the performance are illustrated. The dependence of the performance on the various parameters is investigated and rule-of-thumbs for the parameter values corresponding to 1% RMS error are presented for each simulation condition.

• Journal of Communications and Networks
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• v.15 no.6
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• pp.547-558
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• 2013

Ultra broadband communication systems operated at THz frequencies will require the thorough knowledge of the propagation channel. Therefore, an extensive measurement campaign of 50 GHz wide indoor radio channels is presented for the frequencies between 275 and 325 GHz. Individual ray paths are resolved spatially according to angle of arrival and departure. A MIMO channel is recorded in a $2{\times}2$ configuration. An advanced frequency domain ray tracing approach is used to deterministically simulate the THz indoor propagation channel. The ray tracing results are validated with the measurement data. Moreover, the measurements are utilized for the calibration of the ray tracing algorithm. Resulting ray tracing accuracies are discussed.

• Journal of the Optical Society of Korea
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• v.2 no.2
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• pp.54-57
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• 1998

A noncollinear-phase-matching cone of second harmonic generation(SHG) was observed in a LiNbO3 crystal doped with l mol% MgO. Birefringence refractive indices can be accurately evaluated by analysing the temperature phase matching characteristic for SHG combined with the measurement of the half cone angle. The electro-optic coefficient can also be determined form the observed change of the half cone angle when a DC electric field is applied along the optic axis.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1352-1355
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• 1997

This paper presents the algorithm for estimating the attitude of an underwater vehicle using EFK. The system model is designed by linerizing the nonlinear Euler angle differential equation and the measurements is a speed logger output. The simulation result shows that the estimation lagorithm is adequate for decreasing attitude errors that grow abruptly during the motion with acceleration and rotation. It also shows that we can adapt the algorithm for compensating initial attitude errors generated after initial leveling.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.5
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• pp.666-674
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• 2003

An experimental investigation was performed to study the characteristics of turbulent swirling flow in an axisymmetric annuli. The swirl angle measurements were performed by flow visualization technique using smoke and dye liquid along the test tube. Using the Particle Image Velocimetry method, this study found the time-mean velocity distribution and turbulent intensity with swirl for Re = 20.000. 30.000, 50.000. and 70.000 along longitudinal sections and the results appear to be physically reasonable.