• Environmental Analysis Health and Toxicology
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• v.24 no.3
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• pp.219-229
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• 2009

The purpose of this study is to evaluate the skin whitening effect of Scirpi rhizama ethanol extract (SREE) in an animal model. For the experiment of the study, three brown guinea pigs weighing about 450 g to 550 g were exposed to ultraviolet-B rays on the backs at 500 $mJ/cm^2$ once a week, three consecutive weeks and the total quantity of light was 1,500 $mJ/cm^2$. The artificial tanning spots were divided into six different groups including normal (N), control (C), vehicle control (VC), positive control (PC), experimental 1 (E1, 1% SREE), experimental 2 (E2, 2% SREE) groups. Then, 30 ${\mu}L$ of SREE was transdermaly applied on the artificial tanning spots twice a day and 5 days a week for 8 weeks. With the result of a gross observation, it was found that the degree of pigmentation became apparently thinner in the group applied with E2, compared to the control or the vehicle control group. The melanin index of E2 group was significant lower than the control or the vehicle control group. In the observation with a light microscope, it was found that the degree of melanin pigmentation and S-100 protein expression considerably decreased in the groups applied with SREE, compared to the control or the vehicle control group. With the numerical analysis of melanin pigmentation and S-100 protein expression by using image-analysis software, it was found that the tendency was coincide with the results of microscopic observation.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.53-67
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• 1997

The objective of this study is to provide with the hydro-meteological and probabilistic characteristics of the storms of typhoons that have been passed through the Korean peninsula during the last twenty-three years since 1961. The paths and intensities of the typhoons were analyzed. Fifty weather stations were selected and the rainfall data during typhoon periods were collected. Rainfall data were analyzed for the patterns and probabilistic distributions. The results were presented to describe the areal distributions of probabilistic characteristics. The results obtained from this study can be summarized as follows: 1. The most frequent typhoon path that has passed through the Korean peninsula was type E, followed by types CWE, W, WE, and S. The most frequent typhoon intensity was type B, followed by A, super A, and e types, respectively. 2. The third quartile typhoon rainfall patterns appear most frequently followed by the second, first, and last quartiles, respectively, in Seoul, Pusan, Taegu, Kwangju and Taejon. The single typhoon rainfalls with long rainfall durations tended to show delayed type rainfall patterns predominantly compared to the single rainfalls with short rainfall durations. 3. The most frequent probabilistic distribution of typhoon rainfall event is Pearson type-III, followed by Two-parameter lognormal distribution, and Type-I extremal distribution. 4. The most frequent probability distribution model of seashore location was Pearson type-III distribution. The most frequent probability distribution model of inland location was two parameter lognormal distribution.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.4B
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• pp.270-277
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• 2006

In the wireless adaptive modulation and coding(AMC) systems, the modulation type of user's connection can be changed dynamically. and the ongoing connection might fail due to the change of modulation. In this paper, we approach the AMC-induced CAC problem by focusing on the guaranteed connection. Three kinds of calls, new, handoff, and modulation-changed calls, are considered. We propose a modified guard channel CAC scheme that allows the modulation-changed and handoff calls to use the guard channel. Then we analyze a Markov model for the CAC scheme with long-term AMC in mind. According to the simulation results, the proposed approach reduces the call dropping probability for modulation-changed calls, which suggests the threshold of guard channels can be determined based on the proposed approach.

• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.185-196
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• 2012

The fish community within the lake and 5 tributaries of Lake Chungju in spring and autumn, 2009 was surveyed. In this study, the total 128,506 individuals were collected belonging to 11 families 29 genera 34 species. The most dominant species was Squalidus japonicus coreanus that account for 91.6% of population and 49% of biomass of fish community. In the point of population, dominant species were small-sized species, which became the prey of big-sized predatory species. In the point of biomass, dominant species were predatory species which were large-sized. The most dominant species in lacustrine area was S. japonicus coreanus which accounted for 92.2% of total population and 49.1% of total biomass. The most dominant species of tributary streams was Tridentiger brevispinis which accounted for 66.4% of total population and 55.1% of total biomass. The site of C3 in lacustrine area and Dongdal-cheon in tributary streams collected the most number of species. Through ecological health evaluation of five tributary streams using 8 metric index of biological integrity (IBI) model, two streams (Dongdal-cheon, Kwang-cheon were evaluated as, "B", "good" condition, and Jangsung-cheon obtained grade C indicating "Fair" condition, Jecheon-cheon obtained grade D indicating "Poor" condition based on IBI model. Lepomis macrochirus which was designated as a domestic ecosystem-disturbing alien species with wide food niche have shown tendency to increase the number of individuals since 1991 indicating the adverse effect on not only fish community but also aquatic ecosystem food web of Lake Chungju.

• The korean journal of orthodontics
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• v.42 no.4
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• pp.159-168
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• 2012

Objective: The aims of this study were to investigate mandibular deformation under clenching and to estimate its effect on the stability of orthodontic mini-implants (OMI). Methods: Three finite element models were constructed using computed tomography (CT) images of 3 adults with different mandibular plane angles (A, low; B, average; and C, high). An OMI was placed between #45 and #46 in each model. Mandibular deformation under premolar and molar clenching was simulated. Comparisons were made between peri-orthodontic mini-implant compressive strain (POMI-CSTN) under clenching and orthodontic traction forces (150 g and 200 g). Results: Three models with different mandibular plane angles demonstrated different functional deformation characteristics. The compressive strains around the OMI were distributed mesiodistally rather than occlusogingivally. In model A, the maximum POMI-CSTN under clenching was observed at the mesial aspect of #46 (1,401.75 microstrain [${\mu}E$]), and similar maximum POMI-CSTN was observed under a traction force of 150 g (1,415 ${\mu}E$). Conclusions: The maximum POMI-CSTN developed by clenching failed to exceed the normally allowed compressive cortical bone strains; however, additional orthodontic traction force to the OMI may increase POMI-CSTN to compromise OMI stability.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.63-68
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• 2013

Background: Tumor angiogenesis correlates with recurrence and appears to be a prognostic factor for both breast and prostate cancers. In the present study, we aimed to investigate the correlation of microvessel density (MVD), a measure of angiogenesis, with nuclear pleomorphism, mitotic count, and vascular invasion in breast and prostate cancers at preclinical and clinical levels. Methods: Samples from xenograft tumors of luminal B breast cancer and prostate adenocarcinoma, established by BT-474 and PC-3 cell lines, respectively, and commensurate human paraffin-embedded blocks were obtained. To determine MVD, specimens were immunostained for CD-34. Nuclear pleomorphism, mitotic count, and vascular invasion were determined using hematoxylin and eosin (H&E)-stained slides. Results: MVD showed significant correlations with nuclear pleomorphism (r=0.68, P=0.03) and vascular invasion (r=0.77, P=0.009) in breast cancer. In prostate cancer, MVD was significantly correlated with nuclear pleomorphism (r=0.75, P=0.013) and mitotic count (r=0.75, P=0.012). In the breast cancer xenograft model, a significant correlation was observed between MVD and vascular invasion (r=0.87, P=0.011). In the prostate cancer xenograft model, MVD was significantly correlated with all three parameters (nuclear pleomorphism, r=0.95, P=0.001; mitotic count, r=0.91, P=0.001; and vascular invasion, r=0.79, P=0.017; respectively). Conclusions: Our results demonstrate that MVD is correlated with nuclear pleomorphism, mitotic count, and vascular invasion at both preclinical and clinical levels. This study therefore supports the predictive value of MVD in breast and prostate cancers.

• Journal of Family Resource Management and Policy Review
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• v.13 no.3
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• pp.157-180
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• 2009

The purposes of this study were (a) to examine perceptions of the Legal Delay Before Divorce Program (LDBDP) in Korea among individuals, (b)to predict the need for the LDBDP, and (c) to predict the needs for psychological counseling with predicting variables. Two hundred questionnaires were completed by the clients of a legal aid center in Seoul. The majority of participants knew about and expressed their need for the LDBDP. Participants agreed to the LDBDP because it could prevent impulsive divorce, provide time to prepare for post-divorce life, provide support with counseling, and protect the children in families of divorce. Participants disagreed to the LDBDP because it only delayed the time to divorce, prolonged emotional suffering, and intruded on personal privacy. In the model test, the need for the LDBDP was significantly predicted by marital instability scale, age, education, occupation, the period of living apart, and the status of voluntary divorce. The need for psychological counseling was significantly predicted by age, having at least one child, having at least one minor child, marital period, and need for family life counseling in the suggested model.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.31.2-31.2
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• 2012

We present the Yonsei Evolutionary Population Synthesis (YEPS) models for spectroscopic and photometric evolutions of simple and composite stellar populations. The models are based on the most up-to-date Yonsei-Yale stellar evolutionary tracks and BaSel 3.1 flux libraries, and provide integrated spectroscopic quantities of Lick/IDS system including high-order Balmer absorption-lines. Special care has been taken to incorporate the systematic variation of horizontal branch (HB) morphology as functions of metallicity, age, alpha-element mixture, and helium abundance of simple stellar populations. Our models for normal-helium stellar populations indicate that the realistic modeling of HB and alpha-element brings about 5 Gyr and 0.1 dex differences in age and metallicity estimations, respectively, compared to those without these effects. The HB effect does not depend on the specific choice of stellar libraries and alpha-element enhancements, and this effect is non-negligible even in the metal sensitive absorption indices, such as Mg2 and Mg b. Comparison of the models to observations reveals that the HB and alpha-element effects are critical in understanding otherwise inexplicable phenomena found in globular cluster systems in the Milky Way and nearby galaxies, including the observed bimodality of the line strengths of globular clusters in massive galaxies. In addition, we found that helium-enhanced stellar populations, which are the major sources of extreme HB stars, bring about increased FUV, NUV fluxes, and thus the model colors of those filters become extremely blue. Age dating based on the YEPS model with normal-helium stellar populations reveals that the evidence for 'downsizing' of elliptical galaxies is found not only in the local field but also in Coma cluster, and that the mean age of elliptical galaxies in Coma cluster is about 1.4 Gyr younger than the mean age of those in the local field. We also find that our models with helium-enhanced subpopulations can naturally reproduce the strong UV-upturns observed in giant elliptical galaxies assuming an age similar to that of old GCs in the Milky Way.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.3 s.333
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• pp.39-44
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• 2005

The OFDM modulation and transmission block have been modeled in order to analyse the relationship between the 2.4GHz power amplifier distortion and output ACPR for the IEEE 802.11g wireless LAN. The nonlinear characteristic of the power amplifier has been modeled as AM-to-AM and AM-to-PM using the behavioral model, and the output spectrum is analysed with the phase distortion variation. Also, amplifier back-off value from P1dB to satisfy the required IEEE 802.11g standard spectrum mask s been simulated with modeled phase distortion, and the simulation data have been compared to the measured result by using the pre-distortion technique.

• Korean journal of food and cookery science
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• v.28 no.1
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• pp.67-76
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• 2012

This study examined the optimal ingredient mixing ratio for the preparation of steamed cake containing mugwort (Artemisia princeps var. orientalis) powder. After preliminary studies, the following ingredient ranges were determined; 110~129% sugar, 3~8% mugwort powder, 10~25% oil. Among the different mixture designs, the D-optimal design was chosen for analysis. The results of F-test, specific gravity, viscosity, volume and color values (L, a, b), hardness decided a linear model, while the sensory characteristics (color, taste, texture and overall acceptance) decided a quadratic model. The fitness analysis results showed that in all characteristic, the probabilities were significant within 0.05%; thus, the models were accepted as appropriate. The response surface and trace plot results showed that increasing amounts of mugwort powder decreased the brightness, and increased redness and yellowness. As the level of added oil increased, the softness of the cake increased. Cake samples received low sensory evaluation scores when sugar, mugwort powder, and oil were added above their optimal levels. The optimum formulations by the numerical and graphical methods, were similar, and with the numerical method presented as: sugar, mugwort powder, and oil at 120.7%, 5.1%, and 16.2%, respectively(flour weight basis). The above results demonstrate the feasibility of adding mugwort powder to sponge cake, and therefore, the commercialization of mugwort powder cake marketed as a functional food is deemed possible.