• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.449-469
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• 2011

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.404-410
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• 2020

Background Some patients who need surgery refuse a blood transfusion because of their religious beliefs or concerns about blood-borne infections. In recent years, bloodless surgery has been performed successfully in many procedures, and is therefore of increasing interest in orthognathic surgery. Methods Ten Jehovah's Witnesses who visited our bloodless surgery center for orthognathic surgery participated in this study. To maintain hemoglobin (Hb) levels above 10 g/dL before surgery, recombinant erythropoietin (rEPO) was subcutaneously administered and iron supplements were intravenously administered. During surgery, acute normovolemic hemodilution (ANH) and induced hypotensive anesthesia were used. To elevate the Hb levels to >10 g/dL after surgery, a similar method to the preoperative approach was used. Results The 10 patients comprised three men and seven women. Their average Hb level at the first visit was 11.1 g/dL. With treatment according to our protocol, the average preoperative Hb level rose to 12.01 g/dL, and the average Hb level on postoperative day 1 was 10.01 g/dL. No patients needed a blood transfusion, and all patients were discharged without any complications. Conclusions This study presents a way to manage patients who refuse blood transfusions while undergoing orthognathic surgery. rEPO and iron supplementation were used to maintain Hb levels above 10 g/dL. During surgery, blood loss was minimized by a meticulous procedure and induced hypotensive anesthesia, and intravascular volume was maintained by ANH. Our practical approach to orthognathic surgery for Jehovah's Witnesses can be applied to the management of all patients who refuse blood transfusions.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5937-5940
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• 2014

Background: This study was conducted as a descriptive-correlational exercise with the aim of determining the effect of student perceptions of social skills on their pro and con perceptions of smoking. Materials and Methods: The study sample comprised 106 students at $6^{th}$, $7^{th}$ and $8^{th}$ grades in three primary schools. The data were collected through socio-demographic data collection form, Social Skill Perception Form and Child Decisional Balance Scale. Data were evaluated by percentage calculation, Student t test and correlation analysis. Results: While the point average of pro perception of smoking of the students with a high point average of social skill perception, was $8.6{\pm}3.1$, in those with a low social skill perception point average it was $10.7{\pm}4.2$, the difference being significant(p=0.012). The respective point averages of con perceptions were $26.8{\pm}3.7$ and $23.5{\pm}3.3$, again significant (p=0.000). While a positive medium level (r=0.410) relationship was determined between the point average of social skill perception and con perception of smoking, a negative low level (r=0.281) relationship was determined with the pro perception of smoking. Conclusions: As the social skill perception point average increases, children's con perceptions of smoking increase and their pro perceptions decrease.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.401-410
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• 2020

This study is to conduct a 12-month f/u survey on changes of metabolic syndrome (MetS) components according to the resting heart rate (RHR) in patients with essential hypertension (HTN) without cardiovascular disease (CVD) complication. We used the KorHR (Korean Hypertension Registry) data and a total of 951 subjects were analyzed using the R statistical program. As a result of this study, it was found that the risk and changes of MetS components differs according to the RHR group with first and revisit hypertensive patients. Therefore, guidelines for customized RHR control for first and revisit hypertensive patients should be prepared. Also, it is necessary to prepare various interventions to control the RHR. Through this, it is intended to prevent the occurrence of CVD caused by HTN, which is a representative chronic disease, to improve the quality of life of patients and their families as well as to contribute to increasing the efficiency in the health care.

• Structural Engineering and Mechanics
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• v.18 no.4
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• pp.389-410
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• 2004

In this study, theoretical and experimental results are presented which were obtained during an investigation of the influence of the $P-{\Delta}$ effect that was caused by the simultaneous changing of the axial load P of the column and the lateral displacement ${\Delta}$ in the external beam-column joints. The increase or decrease of ${\Delta}$ was simultaneous with the increase or decrease of the axial compression load P and caused an additional influence on the aseismic mechanical properties of the joint. A total of 12 reinforced concrete exterior beam-column subassemblies were examined. A new model, which predicts the beam-column joint ultimate shear strength, was used in order to predict the seismic behaviour of beam-column joints subjected to earthquake-type loading plus variable axial load and $P-{\Delta}$ effect. Test data and analytical research demonstrated that axial load changes and $P-{\Delta}$ effect during an earthquake cause significant deterioration in the earthquake-resistance of these structural elements. It was demonstrated that inclined bars in the joint region were effective for reducing the unfavourable impact of the $P-{\Delta}$ effect and axial load changes in these structural elements.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.73-78
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• 1990

Hematological and blood chemical changes of rabbits infected with rabbit hemorrhagic disease virus were studied and the results were summarized as follows: 1. Total leukocyte count ($2,410{\pm}1,076/{\mu}l$), lymphocyte count ($1,582{\pm}632.5{\mu}l$) and heterophil count ($705{\pm}411.1{\mu}l$) were significantly decreased after 24 hours of the infection (p<0.01). However, no significant changes were observed in monocyte, eosinophil and basophil numbers. 2. A significant increase of aspartate aminotransferase (96IU/L), alanine aminotransferase (96IU/L) and alkaline phosphatase ($401.1{\pm}131.8IU/L$) was observed (p<0.01). 3. A moderate increase of BUN ($26.9{\pm}3.6mg/100ml$) and creatinine ($3.2{\pm}1.9mg/100ml$) was observed (p<0.05). 4. No significant changes of r-GTP, thymol turbidity, glucose, cholesterol, albumin, total serum protein, fibrinogen were observed.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.410-414
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• 1992

Numerical identification was carried out for an isolate of Streptomyces strain producing the extracellular p-lactamase inhibitor. Fifty taxonomic unit characters were tested and the data were analyzed numerically using the TAXON program. The isolate was identified to the major cluster 5 of Streptomyces and it was best matched to Streptomyces omiyaensis which is a synonym of Streptomyces exfoliatus. Therefore, it was concluded that the isolate was identified to be a strain (SMF 19) of Streptomyces exjbliatus.

• Food Science and Preservation
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• v.17 no.3
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• pp.410-417
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• 2010

Several extracellular protease-producing bacteria were isolated from Chungkookjang, a traditional Korean food of fermented soybeans, on skim milk agar plates. Among these bacteria, strain D14 exhibited the highest production (15.2 U/mL) and specific activity (40.0 U/mg protein) of extracellular protease activity as assessed on growth in a protease induction medium composed of 1% (w/v) soluble starch, 1.5% (w/v) skim milk, 0.5% (w/v) yeast extract, and 2% (w/v) NaCl. The bacterium was identified as Bacillus subtilis based on morphological and physiological characteristics and 16S rDNA sequence. A BLAST search of 16S rDNA sequences revealed that the isolate was most closely related to Bacillus subtilis subsp. subtilis strain NCIB 3610. The 16S rDNA sequence homology was 99.9%. Our isolate produced the highest level of protease when grown in a protease induction medium containing 1% (w/v) sorbitol and 0.5% (w/v) yeast extract. Fructose and glucose reduced enzyme production to 12.7% and 35.9%, respectively, of the level seen when the strain was grown in medium containing soluble starch. Soytone also reduced enzyme production to 61.4% of the level noted when the strain was grown in medium containing yeast extract.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.6
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• pp.401-410
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• 2020

In this study, a real-time Tactical UAS position compensation system based on image information developed to compensate for the weakness of location navigation information during GPS signal interference and jamming / spoofing attack is described. The Tactical UAS (KUS-FT) is capable of automatic flight by switching the mode from GPS/INS integrated navigation to DR/AHRS when GPS signal is lost. However, in the case of location navigation, errors accumulate over time due to dead reckoning (DR) using airspeed and azimuth which causes problems such as UAS positioning and data link antenna tracking. To minimize the accumulation of position error, based on the target data of specific region through image sensor, we developed a system that calculates the position using the UAS attitude, EO/IR (Electric Optic/Infra-Red) azimuth and elevation and numerical map data and corrects the calculated position in real-time. In addition, function and performance of the image information based real-time UAS position compensation system has been verified by ground test using GPS simulator and flight test in DR mode.

• Journal of Microbiology and Biotechnology
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• v.20 no.7
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• pp.1061-1068
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• 2010

The biological synthesis of nanoparticles has gained considerable attention in view of their excellent biocompatibility and low toxicity. We isolated and purified rhamnolipids from Pseudomonas aeruginosa strain BS-161R, and these purified rhamnolipids were used to synthesize silver nanoparticles. The purified rhamnolipids were further characterized and the structure was elucidated based on one- and two-dimensional $^1H$ and $^{13}C$ NMR, FT-IR, and HR-MS spectral data. Purified rhamnolipids in a pseudoternary system of n-heptane and water system along with n-butanol as a cosurfactant were added to the aqueous solutions of silver nitrate and sodium borohydride to form reverse micelles. When these micelles were mixed, they resulted in the rapid formation of silver nanoparticles. The synthesized nanoparticles were characterized by UV-Visible spectroscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy (EDS). The nanoparticles formed had a sharp adsorption peak at 410 nm, which is characteristic of surface plasmon resonance of the silver nanoparticles. The nanoparticles were monodispersed, with an average particle size of 15.1 nm (${\sigma}={\pm}5.82$ nm), and spherical in shape. The EDS analysis revealed the presence of elemental silver signal in the synthesized nanoparticles. The formed silver nanoparticles exhibited good antibiotic activity against both Grampositive and Gram-negative pathogens and Candida albicans, suggesting their broad-spectrum antimicrobial activity.