• Environmental Engineering Research
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• v.19 no.4
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• pp.395-399
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• 2014

Operation characteristics of the sequencing batch reactor (SBR) process with electro-flotation (EF) as a solid liquid separation method (EF-SBR) were investigated. EF-SBR process showed excellent solid-liquid separation performance which enabled to separate biosolids from liquid phase within 30 min and to extend cyclic reaction time. Although influent organic loading rate was increased stepwise from 5 to 15 g COD/day, food to microorganisms (F/M) ratio could be maintained about 0.3 g COD/g VSS/day in EF-SBR because biomass concentration could be easily controlled at desired level by EF. However, it was impossible to increase biomass concentration at the same level in control SBR (C-SBR) process because solid-liquid separation by gravity settling showed a limitation at higher mixed liquor suspended solids (MLSS) concentration with 60 min of settling time. Total chemical oxygen demand (TCOD) removal efficiency of EF-SBR process was not decreased although influent organic loading rate became 3 times higher than initial value. However, it was seriously deteriorated in C-SBR process after increasing the rate over 10 g COD/day, which was accounted for insufficient organic removal by relatively higher food to microorganisms (F/M) ratio as well as biosolids wash-out by a limitation of gravity sedimentation.

• Journal of Trauma and Injury
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• v.27 no.2
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• pp.33-37
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• 2014

Central venous catheterization through a subclavian approach is indicated for some special purposes but it may cause many complications such as infection, bleeding, pneumothorax, thrombosis, air embolization, arrhythmia, myocardial perforation, and nerve injury. A case involving a mistaken central venous catheterization into the right vertebral artery through the subclavian artery is presented. A 33-year-old man who had deteriorated mentality after head injury underwent an emergency craniotomy for acute epidural hematomas on the right frontal and temporal convexities. His mentality improved rapidly, but he complained of continuous severe pain in the right posterior neck even though he had no previous symptom or past medical history of such pain. Three-dimensional cervical spine computed tomography (3D-CT) was performed first to rule out unconfirmed cervical injuries and it revealed a linear radiopaque material intrathoracically from the level of the 1st rib up to the level of C6 in the right vertebral foramen. An additional neck CT was performed, and the subclavian catheter was indwelling in the right vertebral artery through right subclavian artery. For the purpose of proper fluid infusion and central venous pressure monitoring, the subclavian vein catheterization had been performed in the operation room after general anesthesia induction before the craniotomy. Sufficient anatomical consideration and prudence is essential because inadvertent arterial cannulation at a non-compressible site is a highly risky iatrogenic complication of central venous line placement.

• Research in Community and Public Health Nursing
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• v.27 no.1
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• pp.51-59
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• 2016

Purpose: The purpose of this study is to provide a disease management, nutrition education, and group exercise program for three months to the moderately frail elderly whose physical functions have deteriorated, and to investigate its effects in order to develop an intervention program. Methods: As a quasi-experiment, this study was conducted based on non-equivalence studies designed as a similar experiment. The milk intake group and calcium intake group participated in the disease education, individual nutrition education, and group exercise program for three months, and the control group was visited once in the three months by a nurse who provided disease education, nutrition education, and oral instruction of exercise, and asked them to exercise on their own every day. For the data analysis, ${\chi}^2$-test, ANOVA and $Scheff{\acute{e}}$ test were used. Results: After three months of intervention, there was a significant difference in the frailty level (p=.029) and bone density (p=.001) between the groups. Conclusion: The comprehensive intervention program had an effect on the bone density and the frailty level of the socially-vulnerable and moderately frail elderly, suggesting that the program can be used as a nursing intervention to prevent functional deterioration and damage of the moderately frail elderly.

• Transactions on Electrical and Electronic Materials
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• v.11 no.3
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• pp.93-105
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• 2010

Complementary metal-oxide-semiconductor (CMOS) technology scaling has been a main key for continuous progress in silicon-based semiconductor industry over the past three decades. However, as the technology scaling enters nanometer regime, CMOS devices are facing many serious problems such as increased leakage currents, difficulty on increase of on-current, large parameter variations, low reliability and yield, increase in manufacturing cost, and etc. To sustain the historical improvements, various innovations in CMOS materials and device structures have been researched and introduced. In parallel with those researches, various new nanoelectronic devices, so called "Beyond CMOS Devices," are actively being investigated and researched to supplement or possibly replace ultimately scaled conventional CMOS devices. While those nanoelectronic devices offer ultra-high density system integration, they are still in a premature stage having many critical issues such as high variations and deteriorated reliability. The practical realization of those promising technologies requires extensive researches from device to system architecture level. In this paper, the current researches and challenges on nanoelectronics are reviewed and critical tasks are summarized from device level to circuit design/CAD domain to better prepare for the forthcoming technologies.

• Journal of Korean Society of Rural Planning
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• v.23 no.3
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• pp.121-131
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• 2017

Although the educational facility are an important considerations on a social equity standpoint, educational environment in rural areas has been continuously deteriorated by numerous social problems such as decreasing birth rate and increasing of local school closing. The purpose of this study is to evaluate the accessibility of educational environment in rural areas on village level. First, we evaluate physical accessibility based on legally defined commuting distance. Second, the implication of village population of potential accessibility is analyzed. Lastly, the facility centrality index of each village is estimated for assessing the relations of educational accessibility. The main results of this study are as follows; (1) The accessibility of most villages in Pyeongchang-gun is vulnerable that 81.10% for elementary school, 73.17% for middle school, and 82.32% for high school, respectively; (2) The average commuting distance per student considering estimated number of students for each educational facilities indicated 2.75km for elementary school, 4.37km for middle school, and 5.79km for high school; (3) the facility centrality index is highly correlated to educational facilities but not to village population.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.2
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• pp.103-111
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• 2015

In general, no particularly well-established standards have been in place so far, for the method of evaluating the deteriorated level of pipes and ducts of industrial facilities. For that reason, the evaluation depends upon various studies which are based on the analysis of the residual life, thickness thinning, closure rate, and scale thickness that measure a few specific positions of pipes. It also depends upon the expertise in business operation and the specific techniques conducted by the inspection companies and institutions. This research introduces the concept of measuring units per section and the selection method of measurement points per section. Furthermore, specific methodologies were developed to plan and analyze deterioration level of industrial pipes and ducts by engineers and managers using a section map. Consequently, applying the outcomes from this study to the plant equipment of the incineration facility resulted in saving 42% of the repairing and remodeling cost.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.43-49
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• 2008

The track of high-speed railway get deteriorated according as using it. In that case, the maintenance jobs are needed for improvement of track quality. A scheduling problem for the track maintenance of high-speed railway is to determine the jobs should be performed daily. In the problem, the set of jobs for maintenance is given. Each job has it's parameters such as due date, emergency level, and processing time. In addition, jobs can be worked during a certain fixed time when the train doesn't move. In this study, we developed a mathematical model of the scheduling problem for the maintenance of high-speed railway and solved the problem using the ILOG CPLEX library.

• Journal of the Korean Society for Heat Treatment
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• v.20 no.6
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• pp.306-310
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• 2007

Changes in microstructure and damping capacity with aging time for solutionized Mg-Al alloy have been investigated. Discontinuous ${\beta}\;(Mg_{17}Al_{12})$ precipitates form along the primary grain boundaries, the amount of which increases as the aging time increases. The hardness of the matrix with respect to aging time shows a typical "S" shape, indicating a generation of fine continuous precipitates in the matrix during the aging. The peak level of damping capacity is obtained after 1 hour of aging, over which the damping capacity becomes deteriorated continuously. The formation of optimum density of continuous ${\beta}$ precipitates with fine morphology which would act as pinning points for dislocation lines, might be responsible for the improvement of damping capacity.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.19-26
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• 2006

Building would be deteriorated with time elapse, influenced by its geographic situation, climate and other environmental conditions. In addition, the systematic maintenance could be provided to keep the resident a recent living condition. The existing breakdown maintenance will be changed into the preventive maintenance. The preventive maintenance is required to get the repair time, the repair scope and frequency. In this paper, it aimed at providing the repair time range over the building components, utilizing the relation between the determination curve and the performance recovery through repair. Results of this study are as follows : First, the forecast of the repair time over the building components could be calculated and equalized with the deterioration and performance degree. Second, the repair time range of building components would be provided into five categories and 3rd repair time. Results of this study will set up the long-term repair plan of building, and finally keep an housing condition comfortable.

• Journal of Korean Neurosurgical Society
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• v.44 no.6
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• pp.382-384
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• 2008

Gas forming brain abscess is a rare disease caused by Klebsiella pneumoniae occurring in patients with impaired host defense mechanism such as diabetes mellitus or liver cirrhosis. A 59-year-old man with 2-year history of diabetes mellitus and 20-year history of liver cirrhosis presented to the hospital with headache. On the day after admission, severe headache was developed and he deteriorated rapidly. Brain CT showed a non-enhanced mass including multiple air density as well as surrounding edema seen in the right occipital lobe, and isodensity air-fluid level seen in the right lateral ventricle. Despite emergent ventricular drainage and intraventricular and intravenous administration of antibiotics, his condition progressively worsened to sepsis and to death after 5 days. Bacterial culture of blood and ventricular fluids disclosed a Gram (-) rod, Klebsiella pneumoniae. In this report we review the pathogenic mechanism and its management.