• Journal of Korean Society of Steel Construction
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• v.20 no.6
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• pp.731-740
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• 2008

This paper deals with the fatigue behavior and strength of a new-type of steel-concrete composite bridge deck. The new-type composite bridge deck consists of corrugated steel plate, welded T-beams, stud-type shear connectors and reinforced concrete filler. A total of eight composite bridge deck specimens were fabricated, the fatigue tests were conducted under four-point bending test with three different stress ranges in constant amplitude. According to the test results, the fatigue crack generated at the welding part of the corrugated steel plate, progressed down to the bottom of the steel plate and encountered the crack, which came out from the opposite side at the same position. After the two cracks were connected at the bottom of the steel plate, the lower flange was cut off and the fatigue crack developed up to the T-beam. And the displacements and strains of fatigue test specimens were increasing with cyclic loading number, these were changed sharply at the fatigue failure. The fatigue results are compared with the design S-N curves specified in the Korea Highway Bridge Design Specifications and data in NCHRP 102 and NCHRP 147 report. The new-type composite bridge deck has a stress category of C, which means that new-type composite bridge deck can be designed by the current fatigue design specifications provided for steel members.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.213-217
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• 2010

The use of chloral hydrate and hydroxyzine for oral sedation is most effective in children aged less than 36 months and weighing less than 15 kg. Children who do not belong to this category may show frequent movements due to shallow sedation level, and it can lead to sedation failures. One of the solutions to such sedation failure is conversion to deeper sedation. But, it is not so much of an option, since inhalation anesthetics and devices are required. In this case, conversion from oral sedation to intravenous sedation was successfully achieved without causing injection pain while searching for an intravenous route, by using EMLA cream (Eutectic Mixture of Local Anesthesia). A patient aged 46 months and weighing 15 kg visited the Pediatric Department of Dankook University Dental Hospital. Treatment under TSD(Tell Show Do) was offered, but due to the parent's request, oral sedative measures were taken. Considering prompt converting from oral sedation to iv sedation in case the oral sedation fails, EMLA cream was apllied preemptively. Adequate sedation level could not be achieved after 90 minutes of oral administration, therefore, under the parent's consent, intravenous route was prepared after conscious sedation by $N_2O-O_2$. During treatment, $ETCO_2$, $SPO_2$ and heart rate was monitored every 5 minutes. The patient showed stable vital signs and did not show any movements. The whole procedure took two and a half hours in total, and the treatment was completed without any adverse effects.

• Korean Journal of Clinical Pharmacy
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• v.21 no.2
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• pp.170-181
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• 2011

Purpose: There is considerable variability in rates of hospitalization for patients with community-acquired pneumonia (CAP) in part because of physicians' uncertainty in assessing the severity of illness at presentation. The purpose of the study was to examine the current treatment patterns and factors influencing the Pneumonia Severity Index (PSI) and clinical outcomes in the patient with CAP. Method: The retrospective data collection of the patients with CAP was conducted and the data were reviewed. The collected data included demographic, clinical, laboratory and microbiological medical information. All patients were stratified into three risk groups according to PSI: low risk (PSI score I-II), moderate risk (III) and high risk (IV-V) groups. The examined treatment patterns were the appropriateness of admissions, category of antibiotics used. The prognostic factors associated with PSI and clinical outcomes were examined. Results: One hundred and six patients' medical data were reviewed. The overall appropriateness of admissions was low presenting many of patients were admitted or intensely treated in the hospital despite of lower risk of prognosis and treated with intravenous antibiotics instead of oral fluoroquinolones. Primary pneumonia pathogens were Klebsiella pneumoniae (27%) and Streptococcus pneumoniae (21.6%). Mean LOS was 8.5 days and was significantly longer (10.0days) (p<0.001) in high risk group. The patients with age >65 (p<0.001), diabetes mellitus (p<0.001), mental alteration (p<0.001), and/or $PaO_2$ <60 mmHg (p<0.001) had a tendency to have higher PSI. The prognostic factors associated with longer LOS were age >65 years (p=0.008), mental status alteration (p<0.001), dyspnea (p=0.002) and PSI score (p=0.001). The prognostic factors associated with mortality were congestive heart failure (p=0.038), systolic blood pressure <90 mmHg (p=0.002) and arterial pH <7.35 (p=0.013). Conclusion: Most of patients were found to over-utilize medical service according to appropriateness of admissions. The elderly, mentally altered patients with low $PaO_2$ had higher PSI score with increased risk of LOS. The mortality could be increased in the patient with disease state of congestive heart failure, high blood pressure, and/or acidosis.

• Education of Primary School Mathematics
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• v.20 no.4
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• pp.253-266
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• 2017

The purpose of the study was to investigate the perceptions of Elementary school teachers on mathematics instruction. To do this, 7 test items were developed to obtain data on teacher's perception of mathematics instruction and 73 teachers who take mathematical lesson analysis lectures were selected and conducted a survey. Since the data obtained are all qualitative data, they were analyzed through coding and similar responses were grouped into the same category. As a result of the survey, several facts were found as follow; First, When teachers thought about 'mathematics', the first words that come to mind were 'calculation', 'difficult', and 'logic'. It is necessary for the teacher to have positive thoughts on mathematics and mathematics learning, and this needs to be stressed enough in teacher education and teacher retraining. Second, the reason why mathematics is an important subject is 'because it is related to the real life', followed by 'because it gives rise to logical thinking ability' and 'because it gives rise to mathematical thinking ability'. These ideas are related to the cultivating mind value and the practical value of mathematics. In order for students to understand the various values of mathematics, teachers must understand the various values of mathematics. Third, the responses for reasons why elementary school students hate mathematics and are hard are because teachers demand 'thinking', 'because they repeat simple calculations', 'children hate complicated things', 'bother', 'Because mathematics itself is difficult', 'the level of curriculum and textbooks is high', and 'the amount of time and activity is too much'. These problems are likely to be improved by the implementation of revised 2015 national curriculum that emphasize core competence and process-based evaluation including mathematical processes. Fourth, the most common reason for failing elementary school mathematics instruction was 'because the process was difficult' and 'because of the results-based evaluation'. In addition, 'Results-oriented evaluation,' 'iterative calculation,' 'infused education,' 'failure to consider the level difference,' 'lack of conceptual and principle-centered education' were mentioned as a failure factor. Most of these factors can be changed by improving and changing teachers' teaching practice. Fifth, the responses for what does a desirable mathematics instruction look like are 'classroom related to real life', 'easy and fun mathematics lessons', 'class emphasizing understanding of principle', etc. Therefore, it is necessary to deeply deal with the related contents in the training courses for the improvement of the teachers' teaching practice, and it is necessary to support not only the one-time training but also the continuous professional development of teachers.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.750-754
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• 2014

Quantitative risk analysis has been performed for a pervaporation process for production of high test peroxide. Potential main accidents are explosion and fire caused by a decomposition reaction. As the target process has a laboratory scale, the consequence is considered to belong to Category 3. An event tree has been developed as a model for occurrence of a decomposition reaction in the target process. The probability functions of the accident causes have been established based on the frequency data of similar events. Using the constructed model, the failure rate has been calculated. The result indicates that additional safety devices are required in order to achieve an acceptable risk level, i.e. an accident frequency less than $10^{-4}/yr$. Therefore, a layer of protection analysis has been applied. As a result, it is suggested to introduce inherently safer design to avoid catalytic reaction, a safety instrumented function to prevent overheating, and a relief system that prevents explosion even if a decomposition reaction occurs. The proposed method is expected to contribute to developing safety management systems for various chemical processes including concentration of hydrogen peroxide.

• The Journal of Internal Korean Medicine
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• v.13 no.2
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• pp.57-69
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• 1992

The study has been carried out to investigate of the senile dementia by referring to 35 literratures. The results were as follows ; 1. In oriental medical science, senile dementia is belong to the category of dullness(매病), insanity(癲狂證), weak(虛勞), amnesia(健忘), etc. 2. The cause of senile dementia summarize the phlegm preventid-heart hole(痰迷心竅), marrow lack(髓海不足), aged follow weaking of body and disfunction of the internal organs(年老體弱과 臟腑機能 失調), the bad blood with vatal block(氣滯血瘀), feeling inharmony, etc in the view of oriental medical science and make the vanishment of the cerebral atrophy and the cerebral cell but havn't indicated the remarkable cause in that of western medical science. The diseases with cause make a point of Alzheimer's dementia, frequent infarction dementia, etc and psychological and environmental factor too. The marrow lack is related to Alzheimer's dementia, the feeling inharmony, psychologic and environmental factor, the phlegm prevented-heart hole and bad blood with vatal block, frequent infarction dementia. 3. The senile dementia is related cleary to the function of the internal organs in oriental medical sciences respect Especially in relation to kidney and marrow, it is presented new cause view to solve the cure problem of western medical science is studying its cause only the anatomic pathology with cerebrum and is thinking to solve cure possibility. 4. The symptom of senile dementia is as follows. The obstacle of a aspect of the Language, Emotion, Behavior. mute, speech inversion, sometimes a laugh sometimes a cry, behavior strange, failure of memory etc. 5. The treatment of senile dementia is follows. The methodes of cure apply phlegm changed-mud(豁痰化濁), self-kidney and added marrow(補腎益髓), self-energy and nutritive blood(益氣補血), vital blood(祛瘀活血), peace of mind and relief(安神情志). The medicines of cure make the most of (sesimtang, jwagui-hwan, tonggwuhwalhuel tang) add and subtract, daeboweonjeon, guibitang, and so on.

• Geomechanics and Engineering
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• v.8 no.1
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• pp.113-132
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• 2015

In this study, lime (L), silica fume (SF), and lime-silica fume (L-SF) mix have been used for stabilizing and considering their effects on the soft clay soil. The improvement technique adopted in this study includes improving the behaviour, of a square footing over soft clay through grouting the clay with a slurry of lime-silica fume before and after installation of the footing. A grey-colored densified silica fume is used. Three percentages are used for lime (2%, 4% and 6%) and three percentages are used for silica fume (2.5%, 5%, 10%) and the optimum percentage of silica fume is mixed with the percentages of lime. Several tests are made to investigate the soil behaviour after adding the limeand silica fume. For grouting the soft clay underneath and around the footing, a 60 ml needle was used as a liquid tank of the lime-silica fume mix. Slurried silica fume typically contains 40 to 60% silica fume by mass. Four categories were studied to stabilize soft clay before and after footing construction and for each category, the effectiveness of grouting was investigated; the effect of injection hole spacing and depth of grout was investigated too. It was found that when the soft clay underneath or around a footing is injected by a slurry of lime-silica fume, an increase in the bearing capacity in the range of (6.58-88)% is obtained. The footing bearing capacity increases with increase of depth of grouting holes around the footing area due to increase in L-SF grout. The grouting near the footing to a distance of 0.5 B is more effective than grouting at a distance of 1.0 B due to shape of shear failure of soft clay around the footing.

• Tuberculosis and Respiratory Diseases
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• v.51 no.1
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• pp.59-64
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• 2001

Nonspecific interstitial pneumonia (NSIP) was first described as a new category of idiopathic interstitial pneumonia in 1994. This is a disease with a more insidious onset and has a chronic course. The histological findings are unusual for other idiopathic interstitial pneumonia cases (usual interstitial pneumonia, diffuse interstitial pneumonia, and acute interstitial pneumonia). In contrast to NSIP, acute interstitial pneumonia (AIP) has an acute onset and a fulminant course with the rapid development of respiratory failure. A pathological examination demonstrated characteristic diffuse interstitial fibrosis, hyaline membranes, thrombi, and architectural derangement. Here we report a 48-year-old woman who was diagnosed pathologically NSIP, but with a rapid progressive course similar to AIP.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.3
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• pp.265-272
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• 2012

The applicability of Diabetes Mellitus(DM) in Oriental Medicine might be placed under the category in Wasting-thirst(消渴, WT). However, because of WT having so various concepts, classification, and names in Oriental Medicine, this resulted in confusion in applying WT treatment to DM. WT occurs mainly due to dryness-heat(燥熱) which by depleting 'Fluid and Humor'(津液) makes symptoms of thirst(口渴) swift digestion with rapid hungering(消穀善饑) frequent urination(小便頻數) according to the "Internal Classic"(內經). WT was also called Sodan(消癉), Bidan(脾癉), or Sojoong(消中) in the "Internal Classic", which was caused by not only the disorder of 'five viscera' (五臟), but also the failure of 'three yin and three yang'(三陰三陽). However, the doctors of those days had a tendency to manage WT (including DM) with herbal drugs of dryness-heat or with drugs that recover the pancreas and the kidney, that have a tendency to appreciate that WT is the disease of 'five viscera'(五臟). Accoding to the "Internal Classic"(內經) and "Jinguiyaolue"(金匱要略), WT was appreciated that WT is also due to the disorder of Meridian including 'three yin and three yang'(三陰三陽) theory. Disorder of 'yang brightness'(陽明) or 'reverting yin'(厥陰) would cause Wasting-thirst(消渴), so the 'three yin and three yang'(三陰三陽) theory should be considered in WT treatments. Furthermore, 'yang brightness'(陽明) and 'reverting yin'(厥陰) all belong to 'the door'(闔) in the bolt-door-pivot(關闔樞) theory, and the mean of 'the door'(闔) is the function of storage, so we could understood WT is the wasting disease due to the disorder of 'the door'(闔) system in Meridian. WT should also be understood by the point of the bolt-door-pivot(關闔樞) theory in addition to the 'three yin and three yang'(三陰三陽) theory.

• Journal of Korean Society of Disaster and Security
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• v.6 no.2
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• pp.1-8
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• 2013

This study is concerned with the estimation of fluctuate wind velocity statistic properties in the major cities reflecting the recent meteorological with largest data samples (yearly 2003-2012). The basic wind speeds were standardized homogeneously to the surface roughness category C, and to 10m above the ground surface. The estimation of the extreme of non-Gaussian load effects for design applications has often been treated tacitly by invoking a conventional wind design (gust load peak factor) on the basis of Gaussian processes. This assumption breaks down when the loading processes exhibits non-Gaussianity, in which a conventional wind design yields relatively non conservative estimates because of failure to include long tail regions inherent to non-Gaussian processes. This study seeks to ascertain the probability distribution function from recently wind data with effected typhoon & maximum instantaneous wind speed.