• Clean Technology
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• v.12 no.2
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• pp.67-77
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• 2006

A simple dual sludge process, called as $KNR^{(R)}$ (Kwon's Nutrient Removal) system, was developed for small sewage treatment. It is a hybrid system that consists of an UMBR (Upflow multi-layer bioreactor) as anaerobic and anoxic reactor with suspended denitrifier and a post aerobic biofilm reactor, filled with pellet-like media, with attached nitrifier. To evaluate the stability and performance of this system for small sewage treatment, the pilot-scale $KNR^{(R)}$ plant with a treatment capacity of $50m^3/d$ was practically applied to the actual sewage treatment plant, which was under retrofit construction during pilot plant operation, with a capacity of $50m^3/d$ in a small rural community. The HRTs of a UMBR and a post aerobic biofilm reactor were about 4.7 h and 7.2 h, respectively. The temperature in the reactor varied from $18.1^{\circ}C$ to $28.1^{\circ}C$. The pilot plant showed stable performance even though the pilot plant had been the severe fluctuation of influent flow rate and BOD/N ratio. During a whole period of this study, average concentrations of $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, and TP in the final effluent obtained from this system were 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, and 0.87/0.17 mg/L (with/without poly aluminium chloride(PAC)), which corresponded to a removal efficiency of 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, and 55.4/90.3%, respectively. Excess sludge production rates were $0.026kg-DS/m^3$-sewage and 0.220 kg-DS/kg-BOD lower 1.9 to 3.8 times than those in activated sludge based system such as $A_2O$ and Bardenpho.

• Journal of dental hygiene science
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• v.9 no.3
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• pp.327-338
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• 2009

This study was to develop an instrument for multidimensional measurement of Korean scaling fear (KSF)-1.0 and analyze related factors. A sample of 720 subjects(scaling patients and community people) was studied in Daegu city from November in 2008 to March in 2009. Authors first conceptualized the KSF, item generation, item reduction, and questionnaire formatting were performed in the stage of the development. Item descriptive, missing%, item internal consistency, and item discriminant validity were analyzed in the item-level, also descriptive, floor and ceiling effect were analyzed in the scale-level. Cronbach's alpha, test-retest, inter-dimension correlations, and factor analysis were performed to evaluate the validity and reliability in the new instrument. Confirmative factor analysis was did to evaluate the fit of model. The results for item-level and scale-level were acceptable except item discriminant validity. The reliability for 0.92~0.96 of corelation coefficient range(Cronbach's alpha 0.96~0.98) was high in the test-retest, and there was no significant difference in paired t-test. Item internal consistency(range of pearson corelation coefficient 0.39~0.95) was also high. The result of explanatory factor analysis was the same as the intended dimension structure, also confirmatory factor analysis results revealed that the dimensional structure model were fined well in the evaluation of model fit($x^2$= 1245.66, df=146, p=0.0000; GFI=0.85; AGFI=0.80; RMSEA=0.10). Factors related to KSF by multiple regression were gender($\beta$=0.28, p=0.0004) and teeth brush method($\beta$=-0.15, p=0.0053) in scaling patients, also gender($\beta$=0.25, p=0.0002), educational level($\beta$=0.14, p=0.0155), teeth brush method($\beta$=-0.09, p=0.0229) and time of daily work out($\beta$=-0.10, p=0.0055) were significantly associated with KSF in no scaling group. In conclusion, The results of this study reveal that the new developed measurement scale was reliable and val id instrument for measuring the KSF in dental hygiene patients and community people. We recommend that further research should develop more the instrument for the Korean scaling fear.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.41-47
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• 2016

Background: For the accurate dose assessment in radiation therapy, energy spectrum of the photon beam generated from the linac head is essential. The aim of this study is to develop the technique to accurately unfolding the energy spectrum with the transmission analysis method. Materials and Methods: Clinical linear accelerator and Monet Carlo method was employed to evaluate the transmission signals according to the thickness of the observer material, and then the response function of the ion chamber response was determined with the mono energy beam. Finally the energy spectrum was unfolded with HEPROW program. Elekta Synergy Flatform and Geant4 tool kits was used in this study. Results and Discussion: In the comparison between calculated and measured transmission signals using aluminum alloy as an attenuator, root mean squared error was 0.43%. In the comparison between unfolded spectrum using HEPROW program and calculated spectrum using Geant4, the difference of peak and mean energy were 0.066 and 0.03 MeV, respectively. However, for the accurate prediction of the energy spectrum, additional experiment with various type of material and improvement of the unfolding program is required. Conclusion: In this research, it is demonstrated that unfolding spectra technique could be used in megavoltage photon beam with aluminum alloy and HEPROW program.

• Journal of Korean Home Economics Education Association
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• v.26 no.1
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• pp.1-16
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• 2014

The purpose of this research is to develop a theme-based integrated teaching/learning plan in clothing, food, and housing in home economics and to apply the developed process in classes for evaluation in order to identify the suitability in schools. The theme-based integrated teaching/learning plan developed on the basis of textbooks consist four sub-themes; choosing($1^{st}$ and $2^{nd)$ lessons), using($3^{rd}$ lesson), processing ($4^{th}$ lesson), and alternatives($5^{th}$ and $6^{th}$ lessons) under the main theme of 'green family life'. The results from 20 individual and group activities showed that the students actively solved the problems when the presented cases were related to their own lives or experiences. The opportunity to implement green life through activities motivated students' willingness to proceed in real life. However, it is vital to assist integrated thinking through various examples before beginning due to students with difficulties connecting the issue from one area to the other during the problem-focused activity. The students' ability to solve the activity workbook had been improved as the lessons continued. From the survey questions on the theme-based integrated lessons, all items associated with integration of clothing, foods, and housing were positively responded. Also, questions regarding general understanding, suitability and satisfaction on the teaching/learning process were marked positive. The conclusion could be that the integrated theme related to clothing, food, and housing in our life would be appropriate for green family life. The theme-based integrated teaching/learning plan is effective in understanding the occurrence of green family life in relation with clothing, food, and housing, identifying the practical ideas implementing green life in those areas, and improving the integrated ability to solve the green life related problems. However, this research has its weakness in generalizing the results due to its limited survey respondents and post-evaluation being the only assessment conducted.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.1
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• pp.1-9
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• 1999

To find pertinent soil type and maintenance method for artificial planting ground, the effects of soil compositions{sandy loam(S), vermiculite(V), sandy loam+vermiculite+sand(SVS), sandy loam+ carbonized rice husk+sand(SCS), sandy loam+humus sawdust+sand(SHS)}, and fertilizers (organic, chemical) on plant(kentuckyblue grass) growth were measured and compared from the field experiment. The results are summarized as follows 1. the highest germination rate is found from "vermiculite(V)" and the lowest from "sandy loam(S)" among tested 5 soil compositions. 2. "sandy loam+vermiculite+sand(SVS)" composition shows the highest plant height growth effect (5cm growth during tested 3 months) comparing to other 4 compositions. 3. "sandy loam+vermiculite+sand(SYS)" composition shows the highest ground covering rate after first two months, but it concede its order to "sandy loam+humus sawdust+sand(SHS)" composition after next one month growing. 4. the effects of fertilizers are follows 1) Among the blocks where no fertilizer was tried, the predominant height growth was obvious in "sandy loam+carbonized rice husk+sand(SCS)" and "sandy loam+humus sawdust+sand(SHS)" composition. 2) Among the blocks where chemical fertilizer was tried, relatively positive results were found from "vermiculite(V)" and "sandy loam+vermiculite+sand(SYS)" blocks on germination and growth rate. But on the ground coverage ratio, the effect of "sandy loam+carbonized rice husk+sand(SCS)" composite precede that of those 2 composites. 3) Among the blocks where organic fertilizer was tried, "sandy loam+humus sawdust+sand(SHS)" and "vermiculite(V)" blocks show relatively high ground coverage rate, growth rate than others. 4) When compositional differences were not considered, the block where organic fertilizer was tried shows most positive effects on all 3 measurements-germination ratio, height growth and ground covering.

• Pediatric Infection and Vaccine
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• v.23 no.2
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• pp.128-136
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• 2016

Purpose: This study was done to define clinical characteristics of fever without localizing signs (FWLS) in infants younger than 100 days of age with a goal of providing baseline data to establish a new diagnostic paradigm in the future. Methods: We reviewed medical records of 183 patients who admitted to Daegu Catholic University Medical Center for FWLS younger than 100 days of age from January 2013 to September 2015 retrospectively. Demographic, clinical features and laboratory findings were analyzed. Patients were divided into serious bacterial infection (SBI) and non-SBI groups, and then were compared between two groups to find risk factors for SBI. Results: Among 183 patients, lumbar puncture was performed in 98.9% and CSF pleocytosis was present in 35.9%. Sterile CSF pleocytosis was found in 43% of urinary tract infection (UTI) patients. None had concomitant bacterial meningitis in patients with UTI. As final diagnosis, febrile syndrome without source (25.7%) was most common. Among SBI, UTI was most common (99%). Birth weight, ESR, and CRP were significantly higher in SBI group compared to non-SBI group. Male sex (OR 4.93, 95% CI 1.60-15.24) and pyuria (OR 18.88, 95% CI 6.76-52.76) were identified as risk factors for SBI. Presence of sibling (OR 0.30, 95% CI 0.11-0.83) was significantly lower in SBI group. Conclusions: Our results showed UTI was the most common SBI in young infants with FWLS. Though aseptic meningitis can be coexisting with UTI, lumbar puncture may not be necessary in all patients having UTI.

• Journal of radiological science and technology
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• v.21 no.1
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• pp.79-87
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• 1998

The total-bodies of 10 week-old Sprague-Dawley rats were irradiated with single doses 4.5 and 7.5 Gy, respectively. The effects on plasma and sciatic nerve platelet-derived growth factor(PDGF) concentrations and sciatic nerve PDGF ${\alpha}$ -and ${\beta}$ -receptors densities were examined up to 10 days post-treatment. There was no consistent significant variation in the plasma and sciatic nerve PDGF concentrations in time over the period of study between 4.5 and 7.5 Gy groups. Plasma PDGF concentrations were significantly reduced to 58% of control values between 5 and 10 days with 4.5 Gy and to 51% of control values as percentage of control values between 5 and 10 days with 7.5 Gy after irradiation, respectively(p<0.05). Sciatic nerve PDGF concentrations were increased to 118% of control values at 1 day with 4.5 Gy and to 130% of control values at 1 day with 7.5 Gy after irradiation, respectively(p>0.05). After irradiation, the levels of PDGF ${\alpha}$ -receptor protein density were reduced to 33% of control values at 2 days with 4.5 Gy and to 50% at 2 days with 7.5 Gy, while the levels of PDGF ${\beta}$-receptor protein density were reduced to maximally 26% of control values at 2 days with 4.5 Gy and to 27% at 2 days with 7.5 Gy, respectively, but both initial decreased levels of those were increased subsequently after 2 days following irradiation. These results suggest that the radiation-induced alteration of plasma and sciatic nerve PDGF concentrations, and sciatic nerve PDGF ${\alpha}$ -and ${\beta}$ -receptors densities may be involved in the pathogenesis of bone marrow stem cell and peripheral neuron damages.

• Geophysics and Geophysical Exploration
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• v.14 no.1
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• pp.98-104
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• 2011

Numerical simulation in exploration geophysics provides important insights into subsurface wave propagation phenomena. Although elastic wave simulations take longer to compute than acoustic simulations, an elastic simulator can construct more realistic wavefields including shear components. Therefore, it is suitable for exploration of the responses of elastic bodies. To overcome the long duration of the calculations, we use a Graphic Processing Unit (GPU) to accelerate the elastic wave simulation. Because a GPU has many processors and a wide memory bandwidth, we can use it in a parallelised computing architecture. The GPU board used in this study is an NVIDIA Tesla C1060, which has 240 processors and a 102 GB/s memory bandwidth. Despite the availability of a parallel computing architecture (CUDA), developed by NVIDIA, we must optimise the usage of the different types of memory on the GPU device, and the sequence of calculations, to obtain a significant speedup of the computation. In this study, we simulate two- (2D) and threedimensional (3D) elastic wave propagation using the Finite-Difference Time-Domain (FDTD) method on GPUs. In the wave propagation simulation, we adopt the staggered-grid method, which is one of the conventional FD schemes, since this method can achieve sufficient accuracy for use in numerical modelling in geophysics. Our simulator optimises the usage of memory on the GPU device to reduce data access times, and uses faster memory as much as possible. This is a key factor in GPU computing. By using one GPU device and optimising its memory usage, we improved the computation time by more than 14 times in the 2D simulation, and over six times in the 3D simulation, compared with one CPU. Furthermore, by using three GPUs, we succeeded in accelerating the 3D simulation 10 times.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.457-464
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• 2001

Algal growth potential (AGP) assay using Cochlodinium polykrikoides was conducted in Saryang Island coast where C. polykrikoides red tide occurred annually from July to October 1998. The effects of macro- and micro-nutrients on the growth of C. polykrikoides were specifically evaluated by the algal assay method. Two different types of growth response of C. polykikoides for the addition of nutrients were clearly obseued. For both before and after C. polykrikoides occurrence, the growth of C. polykikoides was significantly stimulated by the addition of either nitrate or ammonium of $50{\mu]M$ with phosphate of $5{\mu}M$. The addition of a single nutrient had no clear effect on the growth of C. polyhikoides and the addition of trace metals, vitamins, and EDTA etc. did not stimulate the algal growth, also. This result indicates that both N and P potentially limited the growth of C. polyhikoides in this period. However, during a bloom of C. polyhikoides, the growth was unlikely to be stimulated by the addition of both macro- and micro-nutrients. At that time the nutrient concentration of Saryang Island coast was $24.33{\mu}M$ for ammonium, $1.61{\mu}M$ for phosphate, and $0.58{\mu}M$ for nitrate, respectively. The concentrations of nutrients increased, on average, 8.2-fold for ammonium and 4.8-fold for phosphate, decreased 3.3-fold for nitrate compared to both before and after the red tide. This result shows that the growth of C. polykikoides was not limited by the nutrients during the bloom in September. Therefore, our results suggest that the C. polykrikoides red tide may outbreak especially when the water is fertilized due to the increased N and P.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.239-248
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• 2004

This experiment was carried out to confirm that phytochrome regulates anthocyanin bio-synthesis during cell suspension culture system of grape or not. In suspension culture of grape, maximum accumulation of anthocyanin was observed at the stationary phase under continuous white light condition. From mono-chromatic light interruption for 24h at the 4th or 7th day on the suspension cultured cells, the anthocyanin accumulation was highly enhanced at the light interruption at 7th day than 4th day under all monochromatic light treatment. However, the cell growth patterns were not affected by any light treatment. In the darkness, the anthocyanin synthesis was very low but remarkably increased by blue light or red light irradiation. However, the increase of anthocyanin accumulation by blue or red light was suppressed by far-red light in the suspension cells of grape. This suppression by far-red light on the anthocyanin synthesis also observed on the cells treated red or far-red light alternatively. These results implied that phytochrome regulation system may be involved in the anthocyanin biosynthesis of the suspension grape cells. By RNA expression analysis, chalcone synthase (CHS) gene was expressed highly by blue and red light but low by far-red light. The synergistic increase of CHS gene expression was also observed at the treatment of blue light followed by red for 24h. This result may explain the increase of anthocyanin accumulation in B/R treatment. Although the expression of phytochrome gene (PHYA or PHYB) was not highly increased by all light treatment (blue, red, and far-red light) the expression of both PHYA gene and PHYB gene was increased a little in cells treated red or far-red light. In grape suspension cells, the red light enhanced the anthocyanin synthesis, whereas the far-red light was suppressed. Although it was not confirmed whether or not phytochrome gene is activated in anthocyanin accumulating grape cells, we believed that anthocyanin biosynthesis in grape cells may be regulated under phytochrome signal transduction system.