• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.7-10
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• 2013

Purpose : This study evaluated the effects of breathing protocols on matching results of PET and CT images using two breathing protocols such as free breathing and acquisition in holding the breathing after the normal expiration in acquiring CT images. Materials and Methods: Whole body FDG PET and CT images of 200 patients (mean age: 58 (range 20~84), 103 males and 97 females) using Discovery VCT (GE Healthcare, Milwaukee, USA). When taking CT images, subjects were asked to breathe freely (free breathing, n=100) or hold the breathing after the normal expiration (Hold, n=100). In the whole body image coronal section where PET and CT were matched, the matched error of the boundary between diaphragm and liver was measured in length. The matched errors were compared according to breathing protocol by age, sex and disease. The verification of statistical significance was made by SPSS 15.0 (SPSS Inc., Chicago, IL, USA) via one way ANOVA. Results: The matched error in all was 0.87 mm. According to breathing protocol, there was no significant difference in matched error as1.01 mm in free breathing and as 0.73 mm in hold breathing (p=.688). The matched error according to sex did not show significant difference as 1.08 mm of males, and 0.93 mm of females in free breathing (p=.517). In hold breathing, there was no significant difference as 0.79 mm of males and 0.66 mm of females (p=.738). There was no significant difference in matched error by age between free breathing and hold breathing (free breathing (p=.728), hold (p=.465). There was no significant difference in matched error by disease between free breathing and hold breathing (free breathing (p=.197), hold (p=.518) Conclusion: The difference in matched error between free breathing and hold breathing was less than 5 mm at 99%. There was no statistically significant difference in matched error by breathing protocol, age and disease. It was proved that there was no difference in matched error between PET and CT images according to breathing protocol during PET/CT scan.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.155-161
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• 2007

In this study, the reactivity of a $SnO_2-ZrO_2$(Sn/Zr = 2/1) catalyst for $SO_2$ reduction by CO was investigated in order to optimize the various reaction conditions such as temperature, gas hourly space velocity (GHSV), and [CO]/[$SO_2$] molar ratio. The reaction temperature in the range of $300{\sim}550^{\circ}C$, space velocity in the range of $5000{\sim}30000cm^3/[g_{-cat}{\cdot}h]$ and [CO]/[$SO_2$] molar ratio in the range of 1.0~4.0 were employed. The optimum temperature, GHSV, and [CO]/[$SO_2$] molar ratio were determined to be $325^{\circ}C$, $10000cm^3/[g_{-cat}{\cdot}h]$, and 2.0, respectively; under these conditions, $SO_2$ conversion was over 99% and sulfur selectivity was over 95%. In addition, the effect of $H_2O$ content on the $SO_2$ reduction by CO was also investigated. As the $H_2O$ content increased from 2 vol% up to 6 vol%, the reactivity and sulfur selectivity decreased. In case of 2 vol% $H_2O$ content, the reaction temperature and [CO]/[$SO_2$] molar ratio were varied in the range of $300{\sim}400^{\circ}C$ and 1.0~3.0. The optimum temperature and [CO]/[$SO_2$] molar ratio were $340^{\circ}C$ and 2.0, respectively under which $SO_2$ conversion and sulfur selectivity were about 90% and 87%, respectively.

• Korean Journal of Ecology and Environment
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• v.46 no.4
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• pp.488-498
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• 2013

A three-dimensional hydrodynamic model was applied to the Lake Euiam. The lake has three inflows, of which Gongji Stream has the smallest flow rate and poorest water. The dam-storage volume, watershed area, lake shape and discharge type of the Chuncheon Dam and the Soyang Dam are different. Therefore, it is difficult to analyze the water plume and mixing pattern due to the difference of the two dams regarding the amount of outflow and water temperature. In this study, we analyzed the effects of different characteristics on temperature and conductivity using the model appropriate for the Lake Euiam. We selected an integrated system supporting 3-D time varying modeling (GEMSS) to represent large temporal and spatial variations in hydrodynamics and transport of the Lake Euiam. The model represents the water temperature and hydrodynamics in the lake reasonably well. We examined residence time and spreading patterns of the incoming flows in the lake based on the results of the validated model. The results of the water temperature and conductivity distribution indicated that characteristics of upstream dams greatly influence Lake Euiam. In this study, the three-dimensional time variable water quality model successfully simulated the temporal and spatial variations of the hydrodynamics in the Lake Euiam. The model may be used for efficient water quality management.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.465-473
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• 2016

This study was conducted in order to investigate the antioxidant capabilities and quality characteristics of instant porridge made of foxtail millet (Setaria italica Beauv.) from different varieties with different endosperm characteristics and processing using different methods. The two foxtail millet varieties used in this study were waxy foxtail millet, 'Samdachal', and non-waxy foxtail millet, 'Samdame'. The means of processing food to create instant porridge were dry cereal frying, wet cereal frying, freeze drying after steaming, popping, and no treatment. The WAI (water absorption index) of instant porridge made of waxy foxtail millet was higher than that of non-waxy foxtail millet, and popping created the highest WAI among the treatments tested. Whean we analyzed RVA characteristics of non-waxy foxtail millet instant porridge, peak viscosity and setback values were decreased in all processed foxtail millet instant porridge compared to non-waxy foxtail millet instant porridge. In waxy foxtail instant porridge, the peak and final viscosities of processed treated instant porridge increased. The viscosity just after pouring hot water into the instant porridge was higher in waxy foxtail millet porridge treated by freeze drying after steaming, popping, and wet cereal frying; the viscosity of non-waxy foxtail porridge was increased after popping as compared with the other treatments. The polyphenol contents and antioxidant activities were increased in all processed, treated-instant porridge except for freeze dried porridge after steamingnt. The popping treatment showed the highest polyphenol contents (1.5 fold), and ABTS antioxidant activity (1.2 fold), compared to no treatment. Non-waxy foxtail millet porridge produced by popping earned the highest sensory evaluation scores.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.5
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• pp.453-467
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• 2016

Overall risks that can occur in a shield TBM tunnelling are studied in this paper. Both the potential risk events that may occur during tunnel construction and their causes are identified, and the causal relationship between causes and events is obtained in a systematic way. Risk impact analysis is performed for the potential risk events and ways to mitigate the risks are summarized. Literature surveys as well as interviews with experts were made for this purpose. The potential risk events are classified into eight categories: cuttability reduction, collapse of a tunnel face, ground surface settlement and upheaval, spurts of slurry on the ground, incapability of mucking and excavation, and water leakage. The causes of these risks are categorized into three areas: geological, design and construction management factors. Bayesian Networks (BN) were established to systematically assess a causal relationship between causes and events. The risk impact analysis was performed to evaluate a risk response level by adopting an Analytic Hierarchy Process (AHP) with the consideration of the downtime and cost of measures. Based on the result of the risk impact analysis, the risk events are divided into four risk response levels and these levels are verified by comparing with the actual occurrences of risk events. Measures to mitigate the potential risk events during the design and/or construction stages are also proposed. Result of this research will be of the help to the designers and contractors of TBM tunnelling projects in identifying the potential risks and for preparing a systematic risk management through the evaluation of the risk response level and the migration methods in the design and construction stage.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.12 no.2
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• pp.165-178
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• 2001

In order to elucidate the biological etiology and the relationship between the ontogenesis of serotonin system and psychopathology in ADHD, plasma serotonin(5-hydroxytryptamine, 5-HT) and 5-hydroxyindoleacetic acid(5-HIAA) were measured and the correlation between the plasma levels of 5-HT and 5-HIAA and age were evaluated in 46 ADHD patients and 18 control subjects. The ADHD patients were composed of 16 combined type, 10 inattentive type, and 20 hyperactive-impulsive type and the control subjects were communication disorders. The results are summarized as follows：1) There was significant difference in plasma 5-HT levels among combined, inattentive and hyperactive-impulsive and control subjects(ANOVA F=4.33, df 3, 60, p<0.05), and post-hoc test using Scheffe method showed significant difference between the combined type and control group. But, post-hoc tests showed no significant differences between combined and inattentive, combined and hyperactive-impulsive, hyperactive-impulsive and inattentive, hyperactive-impulsive and control and inattentive and control groups. 2) There was no significant differences in plasma 5-HIAA levels among the combined, hyperactive- impulsive, inattentive and control groups(ANOVA F=2.08, df 3, 60, p>0.05). 3) Significant difference in 5-HT level was found between the whole ADHD group(N=46) and the control group(N=18)(T=3.10, df 62, p<0.05). But no significant difference in 5-HIAA level was found between the whole ADHD group and the control group(T=1.90, df 62, p>0.05). 4) Plasma 5-HT and 5-HIAA levels showed no significant correlation with TOVA findings(5-HT：omission pearson correlation 0.10, commision 0.23, reaction time 0.01, variability in attention 0.11, all p>0.05, 5-HIAA：omission 0.21, commision 0.15, reaction time 0.09, variability in attention 0.15, all p>0.05). 5) Plasma 5-HT and 5-HIAA levels showed no significant correlation with attention, hyperactivity and impulsivity based on DSM-IV criteria. 6) Plasma 5-HT and 5-HIAA levels showed no significant correlation with age both in ADHD and control group. These findings show that decreased plasma 5-HT level may play a role in the genesis of ADHD, but this finding has no significant correlation with the psychopathology of ADHD. And we could not find any significant differences in ontogenetic processes in 5-HT. Future studies should be focused on the drug effects, family history and prognosis based on the biochemical subtypes(high and low 5-HT group).

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.9
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• pp.14-23
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• 2010

This paper reports the fabrication of a DVB-T/H System in Package (SiP) that is able to receive and process the DVB-T/H signal. The DVB-T/H is the European telecommunication standard for Digital Video Broadcasting (DVB). An IC-embedded Printed Circuit Board (PCB) process, interpose a chip between PCB layers, has applied to the DVB-T/H SiP. The chip inserted in DVB-T/H SiP is the System on Chip (SoC) for mobile TV. It is comprised of a RF block for DVB-T/H RF signal and a digital block to convert received signal to digital signal for an application processor. To operate the DVB-T/H IC, a 3MHz DC-DC converter and LDO are on the DVB-T/H SiP. And a 38.4MHz crystal is used as a clock source. The fabricated DVB-T/H SiP form 4 layers which size is $8mm{\times}8mm$. The DVB-T/H IC is located between 2nd and 3rd layer. According to the result of simulation, the RF signal sensitivity is improved since the layout modification of the ground plane and via. And we confirmed the adjustment of LC value on power transmission is necessary to turn down the noise level in a SiP. Although the size of a DVB-T/H SiP is decreased over 70% than reference module, the power consumption and efficiency is on a par with reference module. The average power consumption is 297mW and the efficiency is 87%. But, the RF signal sensitivity is declined by average 3.8dB. This is caused by the decrease of the RF signal sensitivity which is 2.8dB, because of the noise from the DC-DC converter.

• Clean Technology
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• v.11 no.3
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• pp.123-128
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• 2005

Among various metal oxides semiconductors, $TiO_2$ is the most studied semiconductor for environmental clean-up applications due to its unique ability in photocatalyzing various organic contaminants, its chemical inertness, and nontoxicity. $TiO_2$, however, has a few drawbacks to be solved such as reactivity mainly working under ultraviolet irradiation (${\lambda}$ < 387 nm) and electron - hole recombination on $TiO_2$. In this study, to extend the absorption range of $TiO_2$ into the visible range and enhance electron - hole separation, we synthesized platinum (Pt) deposited $C-TiO_2$. The presence of Pt as an electron sink has been known to snhance the separation of photogenerated electron-hole pairs and induce the thermal decomposition. The characterization of as-synthesized $Pt-C-TiO_2$ was performed by Transmission Electron Microscopic (TEM), the Brunuer-Emmett-Teller (BET) method, X-ray Diffractometer (XRD), UV-vis spectrometer (UV-DRS), and X-ray Photoelectron Spectroscopy (XPS). In order to estimate the photocatalytic activity of the synthesized materials, the photoelectron Spectroscopy (XPS). In order to estimate the photocatalytic activity of the synthesized materials, the photodegradation experiment of an azo dye (Acid Red 44; $C_{10}H_7N=NC_{10}H_3(SO_3Na)_2OH$)was carried out by using an Xe arc lamp (300 W, Oriel). A 420 nm cut-off filter was used for visible light irradiation. From the results, Pt-deposited $C-TiO_2$ showed a far superior phothdegradation activity to Degussa P25, the commercial product under the irradiation of visible light and enhanced photocatalytic activity of visible-working $C-TiO_2$. This is a useful result into the application for the purification system of dye wastewater using visible energy of sun light.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.120-132
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• 1984

In order to clarify the effect of the fish meat hydrolysate on the growth of lactic acid bacteria(Str. lactis, Str. thermophibus, L. bulgaricus, L. acidophilus, and L. helveticus), the optimum conditions for hydrolyzing the fish meat were examined, and changes of the acid production, viable cell count of lactic acid bacteria and the charge of pH of the culture medium by addition of the fish meat hydrolysate were tested. The results were as follows: 1. When the hydrolysis of back muscle of mackerel was proceeded at $50^{\circ}C$ and at pH 8, for 48 hours adding 6% pancreatin of the protein content in the substrate, the best result was obtained. 2. The composition of the fish meat hydrolysate were 53.6% moisture, 32.4% protein, 1.0% fat, 10.7% carbohydrate, and 3.2% ash. 3. Above 0.1% of the fish meat hydrolysate in the culture medium, the acidity of the culture medium by Sir. lactis and Str. thermophilus were increased remarkably. The acidity of the culture medium by L. acidophilus and L. helveticus were increased in above 0.2% fish meat hydrolysate in the culture medium. but L. bulgaricus was not effected by the fish meat hydrolysate. 4. The pH of the culture medium during incubating Str. laclis and Sir. thermophilus failed obviously by adding the fish meat hydrolysate. But in the cases of L. bulgaricus, L. acidophilus, and L. helveticus, the pH were not changed clearly. 5. The viable cell count in all bacterial strains tested here were elevated by increasing the concentration of the fish meat hydrolysate.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1379-1385
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• 2007

In domestic transitional zone design, there is regulation to prevent generation of irregular substructure behaviors that negatively influence in prevention of plasticity settlement on approach section and contact section as well as relieve overall track rigidity by reducing sectional foundation and track stiffness difference, but design guideline that considers dynamic behavior of transitional track in actual service line is very insignificant. Therefore in this study, characteristics of transitional track dynamic behaviors by substructure stiffness are researched and measured dynamic response of transitional track by substructure stiffness in order to prove correlation between substructure and track and calculate elasticity(stiffness) and track load of transitional track by using measurement and formula to provide basic information for developing design guideline considering dynamic behavior of service line transitional track.