• Journal of the Korean Association of Geographic Information Studies
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• v.3 no.1
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• pp.35-43
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• 2000

The slope gradient of the Korean Peninsula was analyzed by using DEM(DTED level 1). The Peninsula has high percentages of gentle slopes. But low plains and very steep slope regions are scarcely distributed in the Peninsula. Altitude lower than 150m areas are composed of plains and undulated plains. The steepest and most rugged topographies are observed in the range of altitude from 500m to 1,000m areas. The areas of altitude greater than 1,000m show plateau landscapes. By overlapping digital geology maps and the gradient grade maps, We revealed the characteristics of slope regions by geological districts. High latitude with steep slope are well developed in the geological districts of granitic gneiss(ARgr) and gneiss($PR_1$) of the Pre-Cambrian, sandstone of the Paleozoic era(P-T), and sedimentary rocks of the Mesozoic era($J_2$). Low altitude with gentle slope areas are representative in the districts of granite of the Mesozoic era($Jgr_1$), the Cretaceous sedimentary rocks of the Mesozoic era($K_1$, $K_2$) and the Cenozoic strata(N). Basalt extruded the Quaternary($Q_1$) are observed in the areas of very gentle slope but greater than 1,000m altitude.

• Journal of the Korean Geosynthetics Society
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• v.15 no.4
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• pp.79-88
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• 2016

A derelict bridge called WoljungGyo is being restored in Gyeongju, the capital city of ancient Silla. WoljungGyo was originally built in 760AD, and later rebuilt in 1280AD during the Goryeo Kingdom. The bridge lasted in working condition for at least 520 years. The bridge was uncovered to the remains of both abutments and four piers, with only one or two steps remaining. The provenance of the WoljungGyo stone relics was investigated to decide the type of stone for the restoration works. Field survey were carried out in the whole area of Gyeongju-Si with petrological investigation for the stone relics. Results of the study present that Namsan granite was used in those days for building of the WoljungGyo. It is seems that the used stones were obtained from tor or core stone around the Tongil-jeon and Tap-gok area in the east side of Mt. Namsan.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1452-1459
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• 2007

The Dps protein, which is overexpressed in harsh environments, is known to playa critical role in the protection of DNA against oxidative stresses. In this study, the roles of Fur in the expression of the dps gene in Salmonella and the protection mechanisms against oxidative stress in Salmonella cells preexposed to iron-stress were investigated. Two putative Fur boxes were predicted within the promoter region of the S. typhimurium dps gene. The profile of dps expression performed by the LacZ reporter assay revealed growth-phase dependency regardless of iron-status under the culture conditions. The fur mutant, $_X4659$, evidenced a reduced level of ${\beta}$-galactosidase as compared to the wild-type strain. The results observed after the measurement of the Dps protein in various Salmonella regulatory mutants were consistent with the results acquired in the reporter assay. This evidence suggested that Fur performs a function as a subsidiary regulator in the expression of dps. The survival ability of Salmonella strains after exposure to oxidative stress demonstrated that the Dps protein performs a pivotal function in the survival of stationary-phase S. typhimurium against oxidative stress. Salmonella cells grown in iron-restricted condition required Dps for full protection against oxidative stress. The CK24 (${\Delta}dps$) cells grown in iron-replete condition survived at a rate similar to that observed in the wild-type strain, thereby suggesting the induction of an unknown protection mechanism(s) other than Dps in this condition.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1456-1463
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• 2009

Vibrio parahaemolyticus possessing urease-positive property is relatively rare, but such strains consistently exhibit the TDH-related hemolysin (TRH) gene. In this study, we examined the effects of incubation temperature on urease activity expression, using the TH3996 and AQ4673 strains where the enzyme activity is known to be temperature-dependent and -independent, respectively. In the TH3996 strain, $\beta$-galactosidase activity was 4.4-fold lower after $30^{\circ}C$ cultivation than after $37^{\circ}C$ in a ureR-lacZ fusion strain, but temperature dependency was not found in ureD- or nikA-lacZ fusion strains. However, ureR-, ureD-, and nikA-lacZ fusions of the AQ4673 strain was not influenced by incubation temperature. We compared the promoter sequences of ureR between the above two strains. Intriguingly, we detected mismatches of two nucleotides between the two strains located at positions -66 and -108 upstream of the methionine initiation codon for UreR. Additionally, urease activity was not affected by culture temperature at either $30^{\circ}C$ or $37^{\circ}C$ by allelic introduction of the AQ4673 ureR gene into the TH3996 ureR deletion mutant. Taken together, our study demonstrates that the transcriptional factor UreR is involved in the temperature dependency of urease activity, and two nucleotides within the ureR promoter region are of particular importance for the urease activity dependency of V. parahaemolyticus.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.2
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• pp.71-79
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• 2010

Thanks to the great development of technology in radiation, we are now able to reduce radiation exposure to the patients, and the radiographer and expenses in medical sector. We are also trying to produce ideal images which maintain useful information. These kinds of effort are increasing over the world. For that reason, we should get images which include necessary data of patients. Then it also can help to reduce radiation exposure to the patients. Therefore, we need to know the problems that cause a falling off in image's quality and check on generator in case of their electronic and mechanical errors. And moreover, we should anticipate the possibility of devices errors and prevent them with regular quality control. This investigation was conducted in medical institutions, institute of educations and hospitals. They are all in Seongnam-City. We used PMX-III, kVp meter to implement kVp test, mR / mAs output test, light fiel / beam alignment test, Reproducibility of exposure dose, half value layer test, reproducibility of exposure time test. in the case of hospitals, they perceive the importance of regular quality control and organize the regular quality control team so they can be satisfied with the error standard in most experiments. On the other hand, when it comes to medical institutions and institute of educations, they perceive the importance of regular quality control less than hospitals do. Radiographer need to understand the importance of regular quality control and practice it so they can get the fine ideal image with the lower dose to the patient.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.118-126
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• 2002

The Altitude Engine Test Facility(AETF) was built at the Korea Aerospace Research Institute and has been being operated for the gas turbine engines in the class of 3,000 lbf thrust. To enhance the confidence level of AETF to the international level, a series of studies and facility modification have been conducted to improve the measurement uncertainty and reliability. In this paper, some part of the facility evaluation tests performed with a single spool turbojet engine are introduced. Tests were performed simulating the flight conditions as steady state, sea level for various flight speeds (i.e., Mn=0.3, 0.5, 0.7, 0.9). The obtained test results are compared with the predicted values of the engine DECK. The measurement uncertainties of airflow, net thrust, fuel flow and SFC showed 0.791~0.914%, 0.851~1.706%, 1.372~7.348% and 1.642~5.205%, respectively. Thus, from this research, the improvement methods of uncertainties on AETF has been confirmed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.62-70
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• 2002

Methodology of predicting steady performance of gas turbine engine from transient test data was explored to develop an economic performance test technique. Discrepancy of transient performance from steady performance was categorized as dynamic, thermal and aerodynamic transient effects. Each effect was mathematically modeled and quantified to provide correction factors for calculating steady performance. Engine performance tests were conducted at Altitude Engine Test Facility of KARI. The influence of engine inlet/outlet condition change on engine performance was corrected firstly, and then steady performance was predicted from the correction factors. The result was compared with steady performance test data. This correction method showed an acceptable level of precision, 3.68% difference of fuel flow.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.77-88
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• 1994

This experiment was carried out to investigate the effect of sewage sludge compost amended soils on the growth and accumulation patterns of heavy metals in plant parts of Orchardgrass seedlings, changes in physical properties and chemical composition, and heavy metal residue in soils. Mixture ratios of sewage sludge compost and soil(loam) were 100:0, 80:20, 60:40, 40:60, 20:80 and 0:100(control), respectively. The results obtained were as follows; 1. The physical properties and chemical compostion of soils were improved by increase in mixture ratios of sewage sludge compost. 2. The biological yield of Orchardgrass seedlings was increased with mixture ratios of sewage sludge compost. 3. The dry weight of shoot(SH) was increased with both of yield components(NT and WT) and biological yield of Orchardgrass seedlings. 4. The total nitrogen concentrations(TN) of plants was increased with quadratically up to the biological yield of 100% mixture ratio of sewage sludge compost. 5. Lead(Pb) concentration of soil in over the 60% mixture ratios of sewage sludge compost were in excess of limiting level(50ppm) of organic fertilizers.

• Journal of International Academy of Physical Therapy Research
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• v.6 no.1
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• pp.788-794
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• 2015

This study examines changes in walking ability among patients with stroke after applying dual-task training under the condition of visual control and unstable supporting ground; the purpose is to provide reference data for selecting intervention methods that enhance the walking ability of patients with stroke. Among the patients with stroke who received rehabilitation treatment(at Rehabilitation Hospital B in Gyeonggi, South Korea from May 2014 to July 2014), 29 patients were selected as research subjects; all of them understood the purpose and contents of this research and agreed to participate in the experiment. The research subjects were divided into a visual control and unstable supporting ground dual-task(VUDT) group(10 patients), a visual control dual-task(VDT) group(10 patients), and an unstable supporting ground dual-task(UDT) group(9 patients); all of the subjects received 30-minute trainings, three times a week for a total of four weeks. A Timed-Up-and-Go(TUG) test was performed to investigate the change of walking function among the subjects, and a 10m walking test was conducted to measure their walking speed. According to the study results, all three groups showed significant differences after dual-task training; the dual-task training group under the condition of visual control and unstable supporting ground showed the most prominent change. This study confirmed that dual-task training using visual control and unstable supporting ground has a positive impact on the walking ability of patients with stroke. Through the study results, we found that implementing dual-task training under the condition of visual control and unstable supporting ground can more effectively improve the walking ability of patients with stroke, rather than performing visual control dual-task training or unstable supporting ground dual-task training only.

• Journal of Korean Foot and Ankle Society
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• v.14 no.1
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• pp.36-40
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• 2010

Purpose: To investigate the results of surgical treatment of the symptomatic accessory navicular in adolescent. Materials and Methods: 11 patients who were 11-16 years old with symptomatic accessory navicular were identified between 2001 and 2009. Six cases were diagnosed after trauma and 8 cases were diagnosed by accident with painful bony protrusion on medial aspect of foot. In cases after at least 3 months of ineffective conservative treatment, patients were treated by resection of accessory navicular and reattachment of tibialis posterior tendon to the apex of the medial longitudinal arch using periosteum and ligamentous soft tissue without transposition of its course. And then short leg cast was applied for correction of the flat foot (if it is combined) which was molded into the longitudinal arch with the talonavicular joint released and foot inverted during about 6 weeks. Results: All were type II accessory navicular without tibialis posterior tendon lesions. In most cases pain was improved, results were excellent in seven and good in four. Calcaneal pitch angle and talus-first metatarsal angle was improved about $4.64^{\circ}$ and $5.79^{\circ}$ in average. Conclusion: Symptomatic accessory navicular in adolescent might not be associated with the tibialis posterior tendon lesions. The surgical treatment composed of excision of the accessory navicular with simple replication of the tibialis posterior tendon without altering its course led to good results in most cases. The procedure has a low rate of complications. And it is easy to be performed with a good satisfaction.