• Proceedings of the Korean Society of Medical Physics Conference
• /
• 2002.09a
• /
• pp.255-259
• /
• 2002

To reduce the uncertainty in the calibration of radiation beams, absorbed dose to water for high energy electrons is recommended as the standards and reference absorbed dose by AAPM Report no.51 and IAEA Technical Reports no.398. In these recommendations, water is, defined as the reference medium, however, the water substitute solid phantoms are discouraged. Nevertheless, when accurate chamber positioning in water is not possible, or when no waterproof chamber is available, their use is permitted at beam qualities R$\_$50/ < 4 g/cm$^2$ (E$\_$0/ < 10 MeV). For the electron dosimetry using solid phantom, a depth-scaling factor is used for the conversion of depth in solid phantoms to depth in water, and a fluence-scaling factor is used for the conversion of ionization chamber reading in plastic phantom to reading in water. In this work, the properties, especially depth-scaling factors c$\_$p1/ and fluence-scaling factors h$\_$pl/ of several commercially available water substitute solid phantoms were determined, and the electron dosimetry using these scaling method was evaluated. As a result, it is obviously that dose-distribution in solid phantom can be converted to appropriate dose-distribution in water by means of IAEA depth-scaling.

• The Journal of Korean Physical Therapy
• /
• v.11 no.2
• /
• pp.123-130
• /
• 1999

Objectives : This study was to investigate the experience rate and factors related with Low Back Pain(LBP). Methods : Questionnaires were completed by 236 dental hygienists in Taegu city and Kyungpook province in June 23-27, 1999. The solicited information was used to estimate odds ration and $95\%$ confidence intervals for the LBP related factors association. Results : The experience rate of LBP was $78\%$. The experience rate of LBP was significantly associated with scaling posture(odds ratio=2.228)(p=0.0371) and stress with dentist(odds ratio=2.767) (p=0.0136). Conclusions : Data from this study support a statistically significant association between LBP and some factors found in other research to increase the relation with LBP. Study findings may have implications for targeting at dental hygienists for scaling posture education or intervention program.

• Journal of Energy Engineering
• /
• v.22 no.3
• /
• pp.283-286
• /
• 2013

The existing nuclear power plants have been often redesigned by increasing or decreasing electrical power without changing design concept by the request of utility, economic factors or other factors. When the cost of power plant equipment redesigned by changing reactor power and electrical power is estimated, if its quotation is not available in the market place, cost scaling factor(CSF) applies to the cost of existing plant equipment and then the new-designed equipment cost can be calculated. In this paper, we review CSFs according to plant capacity change cases in United State DOE, EPRI, ABB, SWEC and introduce the results applied to Korean PWR 1000MWe and 1400MWe.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2006.03a
• /
• pp.97-104
• /
• 2006

The centrifuge and 1-g shaking table tests were performed simultaneously to compare the dynamic behaviors of loose sands of same geotechnical properties. The prototype soils were 10 m thick liquefiable loose sands. The geometric scaling factors were 20 for 1-g and 40 for centrifuge tests. The excess pore pressure, surface settlement, and acceleration in the soil were measured at the same locations in the 1-g and centrifuge tests. The total excess pore pressure from development to dissipation was measured. In the centrifuge test, viscous fluid was used as the pore water to eliminate the time scaling difference between dynamic time and dissipation time. In the 1-g tests, the steady state concept was applied to determine the unit weight of the model soil, and two different time scaling factors were applied for the dynamic time and the dissipationtime. It is concluded that the 1-g tests can simulate the excess pore pressure of the prototype soil if the permeability of the model soil is small enough to prevent dissipation of excess pore pressure during shaking and the dissipation time scaling factor is properly determined.

• Osong Public Health and Research Perspectives
• /
• v.9 no.6
• /
• pp.340-347
• /
• 2018

Objectives: The aim of this research was to determine intra-oral factors that affect halitosis in young women. Methods: This study was performed between March 2014 to May 2014, and included 35 women in their 20s with good oral health. Correlation and logistic regression analyses were performed to investigate the change in halitosis immediately, and 1 hour after scaling. Results: In both oral gas (OG) and extraoral gas (EG) groups, halitosis was reduced after scaling compared to before scaling. The logistic regression analysis of oral state factors in OG showed that as oral fluid [odds ratio (OR) = 0.792, p = 0.045] and dental plaque (OR = 0.940, p = 0.016) decreased by 1 unit, the OR in the OG group decreased (> 50). In addition, as glucose levels in the oral cavity (OR = 1.245, p = 0.075) and tongue coating index (OR = 2.912, p = 0.064) increased by 1 unit, the OR in the OG group increased (> 50). Furthermore, in the EG group, as oral fluid (OR = 0.66, p = 0.01) and dental plaque (OR = 0.95, p = 0.04) decreased, the OR in the EG group decreased (> 50) significantly. Conclusion: To control halitosis, it is necessary to increase oral fluid and decrease the amount of tongue plaque. Furthermore, maintaining a healthy oral environment, aided by regular scaling and removal of dental plaque, may significantly control halitosis.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.8 no.4 s.23
• /
• pp.120-129
• /
• 2005

To analyze a blast effect of developed explosives, three different kinds of aluminized tastable explosives and melted cast explosive TNT were used. Conventional explosive TNT was used as a reference. Each tested explosive charge of 340mm diameter spherical type was initiated at the charge center with DXD-65(${\sim}750g$) booster and RP-87 EBW detonator. Thirteen piezo type pressure sensors were located at a range from 4 to 50m away from the charge. From the blast wave profiles, we calculated a peak blast pressure and impulse of the explosion. The calculated pressures and in pulses were converted to TNT Equivalent Weight(TEW) factor by the scaling ]aw method. The average TEW factors based on the blast pressure of TX-01, TX-02, TX-03, TX-04 were 1.298, 1.05, 1.266, 1.274 and the average TEW factors based on impulse were 1.504, 1.686, 1.640, 1.679. From the results, we concluded that TEW factors based on blast pressure and based on impulse of aluminized explosives were superior to TNT. This results are owing to the high contents of aluminum in formulations.

• Journal of Navigation and Port Research
• /
• v.34 no.2
• /
• pp.117-122
• /
• 2010

Since fuzzy controllers are nonlinear, it is more difficult to set the controller gains and to analyse the stability compared to conventional PID controllers. This paper proposes a fuzzy PD+I controller for tracking control which uses a linear fuzzy inference(product-sum-gravity) method based on a conventional linear PID controller. In this scheme the fuzzy PD+I controller works similar to the control performance as the linear PD plus I(PD+I) controller. Thus it is possible to analyse and design an fuzzy PD+I controller for given systems based on a linear fuzzy PD controller. The scaling factors tuning scheme, another topic of fuzzy controller design procedure, is also introduced in order to fine performance of the fuzzy PD+I controller. The scaling factors are adjusted by a real-coded genetic algorithm(RCGA) in off-line. The simulation results show the effectiveness of the proposed fuzzy PD+I controller for tracking control problems by comparing with the conventional PID controllers.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.48 no.1
• /
• pp.36-43
• /
• 1999

This paper proposes a new hybrid genetic algorithm for auto-tuning fuzzy controllers improving the performance. In general, fuzzy controllers use pre-determined moderate membership functions, fuzzy rules, and scaling factors, by trial and error. The presented algorithm estimates automatically the optimal values of membership functions, fuzzy rules, and scaling factors for fuzzy controllers, using a hybrid genetic algorithm. The object of the proposed algorithm is to promote search efficiency by the hybrid optimization technique. The proposed hybrid genetic algorithm is based on both the standard genetic algorithm and a modified gradient method. If a maximum point is not be changed around an optimal value at the end of performance during given generation, the hybrid genetic algorithm searches for an optimal value using the the initial value which has maximum point by converting the genetic algorithms into the MGM(Modified Gradient Method) algorithms that reduced the number of variables. Using this algorithm is not only that the computing time is faster than genetic algorithm as reducing the number of variables, but also that can overcome the disadvantage of genetic algoritms. Simulation results verify the validity of the presented method.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.8
• /
• pp.3942-3961
• /
• 2019

Recently, the models of deep super-resolution networks can successfully learn the non-linear mapping from the low-resolution inputs to high-resolution outputs. However, for large scaling factors, this approach has difficulties in learning the relation of low-resolution to high-resolution images, which lead to the poor restoration. In this paper, we propose Stage Generative Adversarial Networks (Stage-GAN) with semantic maps for image super-resolution (SR) in large scaling factors. We decompose the task of image super-resolution into a novel semantic map based reconstruction and refinement process. In the initial stage, the semantic maps based on the given low-resolution images can be generated by Stage-0 GAN. In the next stage, the generated semantic maps from Stage-0 and corresponding low-resolution images can be used to yield high-resolution images by Stage-1 GAN. In order to remove the reconstruction artifacts and blurs for high-resolution images, Stage-2 GAN based post-processing module is proposed in the last stage, which can reconstruct high-resolution images with photo-realistic details. Extensive experiments and comparisons with other SR methods demonstrate that our proposed method can restore photo-realistic images with visual improvements. For scale factor ${\times}8$, our method performs favorably against other methods in terms of gradients similarity.

• Journal of Korean society of Dental Hygiene
• /
• v.17 no.3
• /
• pp.369-380
• /
• 2017

Objectives: The purpose of this study is to investigate the effect of preventive treatment experience on scaling fear level. Methods: A total of 259 adults who had visited the dental clinic were analyzed. The results were summarized as follows. Statistical analysis of the collected data was performed using the SPSS WIN 20.0 statistical program. The general characteristics, scaling experience, and the characteristics of the subjects were analyzed. Frequency of scaling according to general characteristics was analyzed by independent sample t-test, Scaling fears according to treatment experience were tested by t-test. Correlation analysis was performed for scaling fears according to the reliability of dental hygienist. Regression analysis was carried out to investigate factors affecting scaling fear. Results: Level of fear during scaling was higher in females (3.03) than in males (2.54) and that after scaling was scored higher in females (2.68) than in males (2.34) by general characteristics (p<0.001). The adults who were not healthy in oral health showed the highest levels of fear during (3.29) and after (3.00) scaling by oral health status (p<0.001). Adults who had brushing education experience showed lower fear level than those who did not after scaling (p<0.01) according to the experiences of preventive treatments. With respect to the correlation of trust level to the dental hygienists with the scaling fears, it showed higher in the trust level (-0.688) as lower level of scaling fear (-0.642) in the scaling (p<0.01). Confidence level of dental hygienist (-0.661), brushing education experience (-0.121), and oral health status (-0.121) were influenced upon the regression analysis. Conclusions: Oral health education and dental hygiene education are increasing. It is thought that active efforts are needed to promote and maintain oral health.