• Particle and aerosol research
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• v.4 no.2
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• pp.37-50
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• 2008

Concerns on centrifugal classifiers, of which have cut sizes are below few micrometers, have been increased and it is prospected to be used in extensive industries, such as manufacturing the fine minerals, cosmetics, advanced electric materials, and life science. This paper reviews the recent progress of research and development on the centrifugal classifiers. General categorization of classifiers for feeds was assessed and separation mechanism of the classifiers was followed. History of centrifugal classifiers was explored and some points to be improved were briefly indicated. Fundamental theory of the classification by centrifugal classifiers was pearly studied, and advanced and further understandings on factors affecting the separation or grading efficiency are described. Factors determining the classification precision and efficiency of centrifugal classifiers, such as geometry, rotational speed and inclined angle of rotating vanes, feed and air flow rates, and rotor dimensions are reviewed.

• Journal of Aerospace System Engineering
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• v.8 no.2
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• pp.21-26
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• 2014

The aircraft manufacturers are constantly driving to reduce manufacturing lead times and cost at the same time as the product complexity increases and technology continues to change. Integrated Modular Avionics (IMA) is a solution that allows the aviation industry to manage their avionics complexity. IMA defines an integrated system architecture that preserves the fault containment and 'separation of concerns' properties of the federated architectures. In software side, the air transport industry has developed ARINC 653 specification as a standardized Real Time Operating System (RTOS) interface definition for IMA. It allows hosting multiple applications of different software levels on the same hardware in the context of IMA architecture. This paper describes a study that provided the avionics software design for separation of fault and backup of core function to reduce workload of pilot with cost efficiency.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.193-195
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• 2011

An abrupt increase of duct cross-section is frequently encountered in pressure reducing devices, valves of internal combustion engines and in gas pipelines. Supersonic flow in a rectangular duct passing an abrupt increase of cross-section is studied numerically. The behavior of base pressure of the dead-air region at sudden enlargement of the duct is clarified. This investigation concerns the determination of the base pressure, which is independent of the size of the enlarged part. Several flow patterns are identified with different enlargements according to the ratio between the downstream ambient pressure and the upstream reservoir pressure. Base pressure and the resulting shock-structure are highly depending on the size of duct enlargement. For a given duct, base pressure tends to minimum for a particular pressure ratio. In addition, the locations of secondary separation and reattachment points of the jet plume are found with respect to different duct enlargements.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.3
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• pp.259-264
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• 2000

The paper provides the characteristic analyses of porcelain suspension insulators. The comparisons of characteristics were made as a function of failed and unfailed insulators which had ben used in the fields. This paper also describes the failure modes occurred in the fields. The aging of cement corrosion of metal breaking of shed puncture in the head and separation of glaze are different failure modes for porcelain suspension insulators. Among these failure modes the puncture breaking and glaze problems were major concerns in this research. The cracks porosities of porcelain and micro-crystals on the graze were the causes of these failures. These results were confirmed by conducting various failure analyses.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.30 no.3
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• pp.88-99
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• 2019

Objectives: With increasing concerns for the rapidly growing minority population in South Korea, this literature review addressed a range of mental health risks among multiethnic youths (MY) in South Korea by 1) comparing mental health outcomes with those of native-born youths and 2) identifying multiple layers of relevant environmental factors, from family and school relationships to culture. Methods: We reviewed 54 studies that fulfilled specific inclusion criteria. Results: Multiple common risk/protective factors, including family separation, family relationship quality, parental socioeconomic and mental health status, social relationships at school, and cultural acceptance, were noted. Conclusion: In general, empirical evidence indicates that minority youths have relatively heightened risks for emotional and behavioral problems. Future studies must elucidate the complex interplay between multiple risk and protective factors and the long-term adaptation and mental health service utilization of MY.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.276-281
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• 2001

The KSR-III Main Propulsion System configuration of the liquid oxygen (LOX) feed line is analyzed. This feed line includes a tighter radius and cavitation venturi for flow mass flow-rate passive control. There were concerns that these configurations might generate a great flow distortion at the engine interface. Also both the pressure drop at the feed line and any presence of separation area are a great concern according to the propellant flow. To resolve these issues, a computational fluid dynamic analysis was conducted to determine the flow field in the LOX feed lines.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.6
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• pp.1973-1993
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• 2022

Model-driven engineering (MDE) and aspect-oriented software development (AOSD) contribute to the common goal of development of high-quality code in reduced time. To complement each approach with the benefits of the other, various methods of integration of the two approaches were proposed in the past. Aspect-oriented code generation, which targets obtaining aspect-oriented code directly from aspect models, offers some unique advantages over the other integration approaches. However, the existing aspect-oriented code generation approaches do not comprehensively address all aspects of a model-driven code generation system, such as a textual representation of graphical models, conceptual mapping, and incorporation of behavioral diagrams. These problems limit the worth of generated code, especially in practical use. Here, we propose AJFCode, an approach for aspect-oriented model-driven code generation, which comprehensively addresses the various aspects including the graphical models and their text-based representation, mapping between visual model elements and code, and the behavioral code generation. Experiments are conducted to compare the maintainability and reusability characteristics of the aspect-oriented code generated using the AJFCode with the most comprehensive object-oriented code generation approach. AJFCode performs well in terms of all metrics related to maintainability and reusability of code. However, the most significant improvement is noticed in the separation of concerns, coupling, and cohesion. For instance, AJFCode yields significant improvement in concern diffusion over operations (19 vs 51), coupling between components (0 vs 6), and lack of cohesion in operations (5 vs 9) for one of the experimented concerns.

• Journal of Yeungnam Medical Science
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• v.18 no.2
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• pp.145-169
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• 2001

In recent years, health care cost containment concerns have resulted in an increase in outpatient (or same-day) surgery. Many procedures previously performed on an inpatient surgery basis have been shifted to outpatient settings. Anesthesia for outpatient surgery is exactly the same as inpatient anesthesia, except that the primary concern is the selection of patients who can be discharged safely on the day of surgery. The anesthesiologist should have a sound rational basis for choice of pharmacologic agents that are geared to expeditious patient discharge from the hospital. Cost concerns aside, outpatient surgery has many additional advantages in the pediatric setting. It minimizes the length of time the child is hospitalized, decreases separation anxiety, promotes parental involvement in the child's postoperative care in the more congenial environment of home, and decreases risk of nosocomial infection and iatrogenic illness.

• Journal of The Korea Institute of Healthcare Architecture
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• v.26 no.1
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• pp.73-84
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• 2020

Purpose: Though Korean healthcare services have been upgraded, infection and fire had been broken out in general hospitals. And higher concerns about quality assessment made it to clinical laboratory design guideline studies. So, this study investigates the facilities, equipment and personnel of laboratory medicine focusing on more than five hundred fifty bed hospital, and contributes to make guidelines for safety and efficiency in lab. Methods: Questionnaires to supervisor technologist and field surveys to medical laboratories in korean hospitals have been conducted for the data collection. 16 answers have been analysed statistically by MS Excel program. Results: Most of the sample tests such as hematology, clinical chemistry, immunology, transfusion, urinalysis, microbiology and molecular diagnosis are performed by more than 80% in large sized general hospital laboratory. In the test methods, automatic analyzers are used up to 80%, total laboratory automation up to 43% in clinical chemistry and immunology, and manual tests in all sorts of the test. There are placed in single lab or two and three labs above the ground, which are all in semi-open lab. There is some correlation with the number of specimens and the number of lab people depending on the number of hospital beds. Laboratory environment shows that work distance is good, but evacuation path width, visibility, separation of staff area from automatic analyzer, and equipment installations are needed to have more spaces and gears. Most of the infection controls are equipped with mechanical ventilation, air-conditioning, washbasin and wastewater separation, BSC installation and negative pressure lab room. Implications: Although the laboratory space area is calculated considering the number of hospital beds, type of tests and number of staff, hospital's expertise and the samples numbers per year should be taken into account in the planning of the hospital.

• Food Science of Animal Resources
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• v.38 no.1
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• pp.26-42
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• 2018

Today incorporation of natural ingredients as inorganic phosphate replacers has come into prominence as a novel research topic due to health concerns about phosphates. In this study, we aimed to investigate the quality of emulsified chicken meatballs produced with Jerusalem artichoke powder (JAP), either alone or in combination with sodium carbonate (SC) as sodium tripolyphosphate (STPP) replacers. The results showed that naturally dried JAP showed favorable technological properties in terms of water-oil binding and gelling. Emulsion batters formulated with JAP-SC mixture showed lower jelly and fat separation, higher water-holding capacity and higher emulsion stability than control samples with STPP. In final product, incorporation of JAP-SC mixture increased moisture and reduced lipid and energy values, and kept the pH value similar to control. Added JAP lead to increments in $b^*$ values whereas decreases $L^*$ values. Cook yield was similar to control in phosphate-free samples formulated with JAP-SC mix. Either low or medium ratios of JAP in combination with SC managed to protect most of the sensory parameters, while sensory scores tend to decrease in samples containing high levels of JAP. Addition of JAP to formulations presented samples that have equivalent behavior to phosphates in terms of lipid oxidation. In conclusion, our study confirms that utilization of JAP in combination with SC had promising effects as phosphate replacers by presenting natural solutions and providing equivalent quality to standard phosphate containing products.