• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.269-276
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• 2012

The surface characteristics and performance of PTFE (polytetrafluoroethylene) hollow fiber membranes have been systematically investigated at lab- and pilot-scale to assess their application to membrane-bioreactor, particularly for integrating wastewater reclamation and rainwater harvesting. The PTFE membrane expressed some surface features, such as hydrophobicity, which might enhance membrane fouling. However, lab-scale performance and cleaning experiments under various conditions demonstrated that the PTFE membrane could produce the desirable water flux with good cleaning efficiency, implying easy operation and maintenance due to superior chemical resistance of PTFE membranes. Most of effluent water qualities were met with Korean standard for discharge and reuse, except color. Color level was further reduced by blending with rainwater at 75:25 ratio. Based on the lab-scale experimental results, the pilot plant was designed and operated. Pilot operation clearly showed sTable performance with satisfactory water quality, suggesting that PTFE membrane could be applied for decentralized MBR integrated with rainwater use.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.2
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• pp.235-242
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• 2007

Road runoff water includes various heavy metals (zinc, Zn; lead, Pb; copper, Cu; chrome, Cr; cadmium, Cd; etc.) and pathogens (E-coli and coliform). Since these pollutants are significantly harmful to human beings and have negative impact on water streams, numerous studies have been conducted to determine the characterization of these non-point pollutants from road runoff water. However, since these non-point pollutant concentrations vary depending on road traffic, road construction, and road maintenance, measurement of pollutant loadings in different site is necessary to estimate the effect of road runoff water on drinking water source. The objective of this study was to examine the quality of road runoff water from a city bridge in Seoul, Korea. This study was conducted for two years to assess annual discharge pollution loads. In this study, five key heavy metals (Zn, Pb, Cu, Cr, and Cd) and two pathogens (E-coli and coliform) were measured at 18 different events. The pollutant load mass transported was always higher than the corresponding runoff volume for Zn, Cu, and Cd, while Pb and Cr showed similar values between the load mass transported and the corresponding runoff volume. The event mean concentrations were Zn (0.908 mg/L), Pb (0.092 mg/L), Cu (0.141 mg/L), Cr (0.023 mg/L), and Cd (0.006 mg/L). Like Zn, Cu, and Cd, E-coli and coliform values (relatively high in Summer and Fall) are higher at the beginning of each event and decrease afterwards.

• Spatial Information Research
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• v.8 no.1
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• pp.155-170
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• 2000

When we use R-Tree,a spatial index, to find objects matches some predicate, it often leads to an incorrect result of perform filtering step only with MBR. And , each candidates need to be inspected to conform if it really satisfies with given query, so called, 'refinement step'. In refinement step. we should perform disk I/O and expansive spatial operations which is the cause of increasing retrieval costs. Therefore, to minimize the number of candidate after filtering step, two-phase filtering methods were studied, but there was many problems such as inefficiency of filtering,maintenance of additional informations and reconstruction of data resulted from the loss of original information. So , in this paper, I propose an Extended R-Tree which provides ability to retrieve spatial objects only with some simple logical operations using Grid Table, truth table strong the information about the existence of spatial objects, in second filtering step. Consequently , this Extended R-Tree using Grid Filter has low cost of operation for filtering because of efficient second filtering step, and better filtering efficiency caused by high quality of approximation.

• Journal of Korean Clinical Nursing Research
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• v.20 no.2
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• pp.147-161
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• 2014

Purpose: This study was aimed to modify and adapt the previously developed, high-quality enteral tube feeding guidelines for the usage in clinical settings in Korea. Methods: Guideline adaptation process was undertaken according to the guideline adaptation manual version 2.0 developed by NECA (Kim, et al., 2011) and the standardized methodology for nursing practice guideline adaptation (Gu, et al. 2012). Results: The modified and adapted enteral tube feeding guidelines were consisted of 11 domains and 95 recommendations. The domains and numbers of recommendations in each domain were: 4 on general issues, 2 on enteral nutrition indication and discontinue, 6 on enteral nutrition device selection, 12 on enteral tube feeding device insertions, 3 on enteral nutrition formular and choices, 16 on enteral tube feeding start and progress, 20 on enteral tube feeding maintenance and management, 15 on monitoring enteral tube feeding administration, 10 on prevention of error, 5 on medication administration, and 2 on documentation and report. There were 16.1% of the recommendations marked as A grade, 17.8% of B grade, and 66.1% of C grade. Conclusion: The adapted enteral tube feeding nursing practice guideline is to be added to the evidence-based practice guidelines for fundamentals of nursing practice. The guideline is hoped to be disseminated to nurses nationwide in order to improve the efficiency of enteral tube feeding practice.

• Korean Parent-Child Health Journal
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• v.6 no.1
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• pp.31-45
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• 2003

This study is designed to produce basic data on the nursing intervention between infants and mothers after discharge from hospitals. This research is carried by investigating the nursing intervention during their after-delivery staying in the hospitals located in Pusan. The object of this study includes the neonatal wards of 51 hospitals. Data collection was carried from the 3rd of September, 2001 to the 4th of October in the same year. Tools for measurement using in this research is the nursing checklist designed by these researchers. The data were analyzed by using SPSS and the output was produced in frequency and percentage considering general characteristics and nursing activities. On the course of investigation, it was revealed that the average number of items checked are as follows; total beds in one hospital came up to 360.1, the beds in each newborn infant ward came up to 36.1, in each ward the numbers of incubators came up to 9.2 and intensive care unit to 1.7. In each ward 8.4 nurses and 2.9 nurse aids were working at that time. In each hospital, secure of air way, physical examination, eye care, umbilical cord care, maintenance of body temperature, identification of infant, nutritive condition, safety and danger management, infection management, mother-infantile interaction, medical assistant to doctor, medication and discharge education were comparatively well done. But, in case of emotional, social and cognitive aspect of nursing activities through interactions between newborn infants and nurses as substitutes are not reached to the adequate level. In the end, this study hereby suggests that further investigation on the device to facilitate the interaction between newborn infant and nurse as a nursing intervention of high quality.

• The Journal of Korean Association of Computer Education
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• v.3 no.2
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• pp.87-94
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• 2000

Software productivity doesn't satisfy the need of service of software users and software quality isn't improved. Moreover, we still have difficulty in software maintenance. As a plan to counteract solving this crisis, the technology that is called CBSE or Componentware is introduced. Componet Based Software Architecture, one of the technologies associated with CBSE, as a structural description of system, describes both the components composed system of and interaction among these components. Software Architecture provides the technology and the methodology of composition among components in the field of CBSE. is accepted one of core technologies. In this thesis, we analyse information necessary for component specification and then proposed that component specificaton activities using formal specification language Z which is verified with the ability of analysis and logicality. The proposed activities are composed of 9 tasks. By presenting specific 11 products, it is also proposed that component specification activities which is the base of CBSD(ComponentBased Software Development) for reusing.

• Journal of Applied Reliability
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• v.16 no.4
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• pp.295-304
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• 2016

Purpose: This paper presents an application of Markov Process to reliability and availability analysis. In order to do that of analysis, we set up a specific case of Tablet PC and it's usage scenario. The case has it some spares and maintenance and repair processes. Methods: Different configurations of the tablet PC and as well as their functions are defined. The system configuration and calculated failure rates of components are modeled from Windchill Quality Solution. Two models, without a spare and with spare, are created and compared using Markov Process. The Matlab numerical analysis is used to simulate and show the change of state with time. Availability of the system is computed by determining the time the system stays in different states. Results: The mission availability and steady-state condition availability in accordance with the mission are compared and the availability of the system with spares have improved availability than without spares. Simulated data shows that downtime of the system increased which results in greater availability through the consideration of spares. Conclusion: There's many techniques and methods to do reliability and availability analysis and mostly are time-independent assumptions. But Markov Process, even though its steady-state and ergodic properties, can do time analysis any given time periods.

• Corrosion Science and Technology
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• v.14 no.1
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• pp.12-18
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• 2015

Since the operation period of nuclear power plants has increased, the degradation of buried pipes gradually increases and recently it seems to be one of the emerging issues. Maintenance on buried pipes needs high quality of management system because outer surface of buried pipe contacts the various soils but inner surface reacts with various electrolytes of fluid. In the USA, USNRC and EPRI have tried to manage the degradation of buried pipes. However, there is little knowledge about the inspection procedure, test and manage program in the domestic nuclear power plants. This paper focuses on the development and build-up of real-time monitoring and control system of buried pipes. Pipes to be tested are tape-coated carbon steel pipe for primary component cooling water system, asphalt-coated cast iron pipe for fire protection system, and pre-stressed concrete cylinder pipe for sea water cooling system. A control system for cathodic protection was installed on each test pipe which has been monitored and controlled. For the calculation of protection range and optimization, computer simulation was performed using COMSOL Multiphysics (Altsoft co.).

• Journal of Digital Contents Society
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• v.18 no.1
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• pp.133-139
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• 2017

To address the problems caused by such high installation and maintenance cost in the conventional server-based cloud systems, researches on P2P cloud storages have been conducted recently. In this paper, we propose a hierachical overlay structure that can improve the playback quality in P2P cloud storage systems for video transmission. In this structure, after we make groups by clustering the participating peers based on their similarities, we construct subgroups by geographically dividing the peers belonging to a specific group considering the physical proximities among them. Therefore, when a request for video playback is issued, we can minimize the transmission delay by selecting the source peers depending on their locality. By simulations, we show that our proposed hierarchical overlay structure considering the peers' locality outperforms the structure where source peers are selected randomly.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1005-1010
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• 1999

To study the shortening of rigor mortis and changes in the morphological properties of gamma-irradiated pre-rigor bovine muscle (M). Sternomandibularis during post mortem, this experiment was performed with a test of shear force and the observation of the ultrastucture of raw muscle. The time elapsed until maximum shear force values was shortened by gamma irradiation, depending upon the dose. The release of rigor mortis started earlier than control (non-irradiated muscle). A shortening of the length of the Z-line and the maintenance of the sarcomere length by gamma irradiation was observed. The breakdown of the perimysium of muscle bundles was observed more in irradiated samples than in the control. In conclusion, it is considered that gamma irradiation on pre-rigor beef shortens aging-period, improves tenderness and enhances the beef quality.