• Journal of Navigation and Port Research
• /
• v.28 no.10 s.96
• /
• pp.869-874
• /
• 2004

Digital TV broadcasting's resolution or tone quality is very excellent than analog broadcasting and has many advantages including various multimedia functions such as home shopping, home banking, internet search, telecommuting, VOD, etc. In this study, it is essential to analyze the regional electromagnetic environment before Digital TV broadcasting, and therefore we analyzed Busan area's limitation using ETRI propagation model. For maintaining high-quality Digital TV signals, we measure electric field intensity wide and far in Busan including mountains area and high-rise buildings. Generally, it has lower value by a standard ETRI propagation model than simulated value about standard model, but distribution pattern are similar with it. Compared theoretical values with the measured results, they have similar values for flat area but very different values for crowded city area and mountains area So we conclude that ETRI propagation model and theoretical model are not suitable for Busan in a free space.

• Current Optics and Photonics
• /
• v.4 no.1
• /
• pp.31-43
• /
• 2020

The feasibility of the application of terahertz electromagnetic waves in the diagnosis of prostate cancer was examined. Four samples of incomplete cancerous prostatic paraffin-embedded tissues were examined using terahertz spectral imaging (TPI) system and the results obtained by comparing the absorption coefficient and refractive index of prostate tumor, normal prostate tissue and smooth muscle from one of the paraffin tissue masses examined were reported. Three hundred and sixty cases of absorption coefficients from one of the paraffin tissues examined were used as raw data to classify these three tissues using the Principal Component Analysis (PCA) and Least Squares Support Vector Machine (LS-SVM). An excellent classification with an accuracy of 92.22% in the prediction set was achieved. Using the distribution information of THz reflection signal intensity from sample surface and absorption coefficient of the sample, an attempt was made to use the TPI system to identify the boundaries of the different tissues involved (prostate tumors, normal and smooth muscles). The location of three identified regions in the terahertz images (frequency domain slice absorption coefficient imaging, 1.2 THz) were compared with those obtained from the histopathologic examination. The tissue tumor region had a distinctively visible color and could well be distinguished from other tissue regions in terahertz images. Results indicate that a THz spectroscopy imaging system can be efficiently used in conjunction with the proposed advanced computer-based mathematical analysis method to identify tumor regions in the paraffin tissue mass of prostate cancer.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.19 no.4
• /
• pp.414-434
• /
• 1997

Though many genetic and epigenetic alterations have been identified in hamster oral carcinogenesis model, there is no information about the possible role of transforming growth factor related with oral cancer. The purpose of this paper was to find the expression patterns of transforming growth factor alpha and beta during the stages of complete oral carcinogenesis model in hamster. 0.5% 9, 10-dimethyl-1, 2-benzanthracene(DMBA) in mineral oil was topically applied to the buccal pouch of 75 hamster three times a week during the experimental periods. The experimental animals were subdivided into two groups of control and experiment. Only the mineral oil was applied to the control group. 0.5% DMBA in mineral oil was applied to the experimental groups of 6, 8, 10, 12, 14, 16, 18 and 20 weeks. The expression of the $TGF-{\alpha}$ and $TGF-{\beta}$ protein were evaluated by the distribution and intensity of positive cells during the carcinogenesis using the immunohistochemical study. The following results were obtained ; 1. The buccal pouch epithelium of hamster was histologically changed to the dysplasia at 6, 8, 10 weeks, carcinoma in situ at 12 weeks, and squamous cell carcinoma at 14 weeks. 2. The expression of the $TGF-{\alpha}$ was restricted to the parabasal and basal layers of the normal and dysplastic mucosa, but those positive cells were extended to the spinous layers of the epithelium in the carcinoma. 3. The degree of $TGF-{\alpha}$ expression was markedly decreased in the carcinoma at 16, 18, 20. The strong positive staining in the center of cancer islands and weak positive staining in periphery of tumor were seen at the stage of squamous cell carcinoma. 4. The positive index of the $TGF-{\alpha}$ had a tendency to increase with DMBA- applied time. There was a statistically significant difference between 12, 18, 20 experimental group and control group (p<0.05). 5. The expression of the $TGF-{\beta}$ was shown at the cytoplasm of all control and experimental groups, and the parabasal and basal layers of the normal and dyslastic mucosa, but it was shown at the basal layers of the epithelium in the carcinoma. 6. $TGF-{\beta}$ was expressed diffusely at 16, 18, 20 experimental group. The strong positive staining in the center of cancer islands and positive staining in periphery of tumor were seen at the stage of squamous cell carcinoma. From the above findings, the expression of $TGF-{\alpha}$ and ${\beta}$ in oral carcinogenesis model seems to have two formal stages, the first being an overexpression step as reaction to uncontrolled growth and the second being one in which external protein accumulate in the surrounding stroma and intracytoplasm. Overexpression of $TGF-{\alpha}$ and ${\beta}$ may have important cooperative roles for the promotion of cancer and factor of prognosis.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.17 no.4
• /
• pp.10-27
• /
• 2014

HAZUS-MH is a GIS-based computer program that estimates potential losses from multi-hazard phenomena: earthquakes, floods and hurricanes. With respect to seismic disaster, characteristics of a hypothetical or actual earthquake are entered into HAZUS. Then HAZUS estimates the intensity of ground shaking and calculates the correspondent losses. In this study, HAZUS was used as a part of the preparations of the future seismic events at a coastal plant facility area. To reliably characterize the target facility area, many geotechnical characteristics data were synthesized from the existing site investigation reports. And the buildings and facilities were sorted by analyzing their material and structural characteristics. In particular, the study area was divided into 17 blocks taking into account the situation of both land development and facility distribution. The ground conditions of blocks were categorized according to the site classification scheme for earthquake-resistant design. Moreover, seismic fragility curves of a main facilities were derived based on the numerical modeling and were incorporated into the database in HAZUS. The results estimated in the study area using HAZUS showed various seismic damage and loss potentials depending on site conditions and structural categories. This case study verified the usefulness of the HAZUS for estimating earthquake losses in coastal facility areas.

• Physical Therapy Korea
• /
• v.19 no.4
• /
• pp.24-31
• /
• 2012

The aim of this study was to investigate the effectiveness of self-stretching exercises for iliotibial band (ITB) (Side-lying; right hip and knee were flexed to support the pelvis while left hip was extended and adducted, Standing A; side-bending of the trunk on standing with crossed leg, Standing B; same as Standing A, except the hands were clasped overhead and shifted right side, and Standing C; same as Standing B, except moving the arms diagonally downward) to help determine the most effective self-stretching method to stretch ITB. Twenty-one healthy subjects who do not have ITB shortness from Yonsei University (14 men and 7 women) between the ages of 18 to 28 years voluntarily participated. Ultrasound was performed to measure the thickness of the ITB between the long axis of the ITB and the level parallel to the lateral femoral epicondyle during four self-stretching exercises. All data were found to approximate a normal distribution. We used a one-way repeated-measures analysis of variance (ANOVA) to compare the thickness of the ITB among all self-stretching exercises. The level of significance was set at ${\alpha}$=.05. The ANOVA was followed by Bonferroni's correction. The overall mean of ITB thickness was $1.14{\pm}.4$ mm (${\pm}$ standard deviation) in resting status. The change in the ITB thickness in percentages between the tested position of each self-stretching exercises and resting status was significant (p<.05) (Side-lying $26.62{\pm}10.18%$ with 95% confidence interval [CI]=21.99~31.25%; Standing A $29.46{\pm}16.19%$ with 95% CI=22.09~36.84%; Standing B $44.06{\pm}14.82%$ with 95% CI=37.31~50.81%; Standing C $53.76{\pm}12.1%$ with 95% CI=48.25~59.29%). Results indicated significant differences among four self-stretching exercises except Side-lying versus Standing A (p<.01). Based on these findings, the Standing C self-stretching exercise was the most effective in stretching the ITB thickness among four types of ITB self-stretching exercises. Additionally, the Side-lying self-stretching exercise using gravity to stretch the ITB is recommended as a low-load (low-intensity), long-duration stretch.

• Journal of Korean Society of Forest Science
• /
• v.102 no.3
• /
• pp.446-454
• /
• 2013

The present study investigated the biological agents and environmental conditions of the habitats of the Kirengeshoma koreana, a class 2 endangered species class according to the South Korean Ministry of Environment (MOE), elucidated the structural characteristics of the forest stands in the habitats with the importance value and the diversity index, conducted comparative analysis of the factors, and explored their relationship with environmental factors. According to the results of direction analysis of natural habitats of the Kirengeshoma koreana, the direction was distributed to the north or the northeast, and the slope amounted to $15-40^{\circ}$, thus demonstrating that the slope has little effect. In addition, the results showed that the distribution of Kirengeshoma koreana populations dramatically increased starting in areas at least 600 m above the sea level and that the relative light intensity was 3.79% on an average. Most populations were native to gorges and crevices between rocks so that they mainly tended to inhabit areas that could see soil loss in times of precipitation. In addition, a considerable number of the populations were close to hiking trails as well, thus leading to concerns about their artificial destruction. The soil of layer a in the main growth space of the Kirengeshoma koreana was analyzed and turned out to be strongly acidic, measuring pH 4.45-4.89 (average: 4.68). All investigation sections were typical natural broad-leaved tree areas, and, judging from the fact that the Kirengeshoma koreana was most likely to appear in colonies of the Mongolian oak tree (Quercus mongolica Fisch. ex Ledeb.), the Mongolian oak tree seems to be the species of tree that has the greatest effect on the inhabitation of the Kirengeshoma koreana.

• Journal of the Korean Geotechnical Society
• /
• v.31 no.8
• /
• pp.5-15
• /
• 2015

One-dimensional rainfall laboratory tests using gneissic weathered soil were conducted to investigate effect of antecedent rainfall on infiltration characteristics. Experimental results using samples from Chuncheon and Chungju sites showed that rainfall onto the ground surface decreased initial negative pore water pressure of unsaturated soils, which recovered gradually after the end of rainfall. Rainfall intensity increases water infiltration rate, and infiltration rate during main rainfall is faster than that of the preceding rainfall. It is considered that higher water saturation after antecedent rainfall increases water infiltration rate during main rainfall. In particular, Chungju sample with higher clay content had slower recovery of negative pore water pressure and infiltration rate. Numerical results using finite element slope stability analysis showed that reduction of initial negative pore pressure due to rainfall infiltration deteriorates slope stability, and diffusion of pore water pressure after the end of rainfall further reduces FS of the slope in the short term. Main rainfall after prior rainfall further reduced factor of safety of the unsaturated slope. Pattern of antecedent rainfall has a significant impact on the magnitude and distribution of initial pore water pressure in unsaturated soils which are controlling factor to assess factor of safety of unsaturated slope during rainfall.

• Journal of the Korean Ceramic Society
• /
• v.33 no.11
• /
• pp.1292-1300
• /
• 1996

In-site X-ray diffraction measurements under electric field up to 20kV/ cm were carried out on PLZT (x/70/30) with x=7.5, 8.0, 8.5, and 10.5 All of PLZT belonged to cubic phases. At x=7.5, 8.0 and 8.5 PLZT behaved as an antiferroelectric under low electric fields up to 4-8 kV/cm. PLZT became ferroelectric at the higher electric fields. The high-temperature measurements on the dielectric constants of PLZT with x=7.5, 8.0 and 8.5 showed that they were similar to relaxor ferroelectrics and underwent a diffuse phase transition from antiferroelectrics to paraelectrics at 50-7$0^{\circ}C$. Their P-E hysteresis curves confirmed that they were antifer-roelectrics. The broad distribution of Curie points suggests that there is a significant disorder of cations and vacances in the crystal structure of those PLZT due to La-substitution. The variation of the lattice strain of PLZT(10.5/70/30) with electic field was very small and did not show any hysteresis confirming that it was paraelectric. The degree of the electric-induced strain variation decreased as La doping increased. In PLZT(7.5/70/30) the intensity of 110 reflection changes sensitively by applying electric field. Some domains with polarization parallel to [110] appeared to be developed in the field-induced ferroelectric phase of the PLZT.

• Journal of the Korean earth science society
• /
• v.32 no.4
• /
• pp.373-387
• /
• 2011

In this study, four types of sensitivity experiments (EG, EE, NG, NE; E: ERA-Interim, N: NCEP/DOE2, G: Grell scheme, E: Emanuel scheme) were performed to evaluate the simulation skills of RegCM4 released in July 2010 over the CORDEX (COordinated Regional Downscaling EXperiment) East Asia domain based on the combinations of boundary conditions (BC: ERA-Interim, NCEP/DOE2) and the cumulus parameterization schemes (CPS: Grell, Emanuel) for the 1989. The surface air temperature and precipitation data observed by the Korea Meteorological Adminstration were used to validate the simulation results over South Korea. The RegCM4 well simulates the seasonal and spatial variations of temperature but it fails to capture the seasonal and spatial variations of precipitation without consideration of the BC and CPS. Especially the simulated summer precipitation amount is significantly less in EG, NG, and NE experiments. But the seasonal variation of precipitation including summer precipitation is relatively well simulated in the EE experiment. The EE experiment shows a better skill in the seasonal march of East Asia summer monsoon, distribution of precipitation intensity and frequency than other experiments. In general, the skills of RegCM4 for temperature and precipitation are better during winter than summer, and in Emanuel than Grell schemes. The simulation results are more impacted by cumulus parameterization schemes than boundary conditions.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.3
• /
• pp.301-306
• /
• 2020

The vertical garden is an environment where plants have many limitations in their growth. In particular, the upper and lower parts of the foundation are characterized by unbalanced moisture distribution. And although it may vary depending on the installation location of the light, generally the base of the light is not in desperate need for plants to grow due to shade. The purpose of this study was to identify the physical characteristics of the vertical garden based on Felt through experiments, classify the location characteristics of the media, and suggest the method of installing the water quantity water frequency, and lighting according to the location characteristics of the foundation. As a result, it was found to be most appropriate to use a 4mm base for the vertical garden and to have an irrigation of about 10 minutes once every 6 hours. In addition, it was found that in order to create a light condition for sufficient growth of plants, light bulbs should be installed at the upper and lower parts of the foundation. As a result of irrigation and lighting tests, the results of the above-mentioned plants need to be referred to in selecting plants that are introduced to vertical gardens, as the results show that the upper part of the foundation has a lower moisture rate and a stronger light than the lower part, and the lower part has a higher moisture rate and a weaker light than the upper part. In the future, we would like to present more accurate methods of selecting and maintaining plants by conducting plant experiments using the underlying characteristics found in this study.