• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.12
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• pp.605-619
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• 2014

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. 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) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.2
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• pp.143-153
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• 2008

Objective: To investigate the effects of aromatase inhibitor on reproductive hormone profiles and evaluate it's ovulation inducing capability in anovulatory infertile women. Methods: We quantified the blood levels of reproductive hormones from 30 healthy normal cycling women in natural cycle (control) and letrozole medicated cycle (study). LH, FSH, estradiol, testosterone, DHEA-S were quantified on third, 11th, 21th day in both cycles, and on 21th day, progesterone was added. Sixth anovulatory infertile women received either letrozole or clomiphene citrate for ovulation induction (n=30 in each groups). We compared the clinical parameters such as ovulation rate, pregnancy rate, the day of LH surge, number of follicles and endometrial thickness, cervical mucus amount, spinnbarkeit, mean diameter of follicles on the day of LH surge. Results: Letrozole had no effect on the LH, FSH, estradiol, DHEA-S secretion but there were significant increase in testosterone level on day 11 and progesterone level on day 21 in letrozole medicated cycle compared than control cycle ($0.40{\pm}0.16$ vs $0.28{\pm}0.11\;ng/ml$, p=0.002, $18.18{\pm}13.07$ vs $8.38{\pm}7.64\;ng/ml$, p=0.001, respectively). In comparison between letrozole and clomiphene groups, there were no significant difference in ovulation rate, pregnancy rate, number of mature follicle, mean diameter of follicles, but showed earlier LH surge, thicker endometrium, more cervical mucus, and higher spinnbarkeit in letrozole group ($12.12{\pm}2.46$ vs $14.52{\pm}3.18$ days, p=0.006, $10.48{\pm}1.23$ vs $8.52{\pm}0.93\;mm$, p=0.000, $2.04{\pm}0.61$ vs $1.57{\pm}0.59$, p=0.012, $6.00{\pm}1.12$ vs $4.95{\pm}1.61\;cm$, p=0.003, respectively). Conclusion: Letrozole may augment folliculogenesis and improve the endometrial condition for implantation in normal cycling women. Ovulation efficacy of letrozole in anovulatory women was comparable to clomiphene citrate and letrozole may be more physiological in ovulation induction.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.2
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• pp.86-93
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• 2016

Performance tests of a 75-tonf liquid rocket engine turbopump were conducted. The performance of sub-components - two pumps and a turbine - and their power matching were measured and examined firstly near the design speed under the LN2 and kerosene environment. In the real propellant - LOX and kerosene - environment tests, design and off-design performance of turbopump were fully verified in regime of the rocket engine operation. During the off-design performance tests, turbopump running time was set longer than the engine operating time to verify the pump operability and set the pump inlet pressure close to design NPSHr to investigate pump suction capability in parallel. It has been found that developed-turbopump satisfied all of the engine required performances.

• KSBB Journal
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• v.23 no.6
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• pp.519-524
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• 2008

Monacolin-K is a strong anti-hypercholesterolemic agent produced by Monascus sp. via polyketide pathway. High-yielding mutants of monacolin-K were developed through rational screening strategies adopted based on understanding of monacolin-K biosynthetic pathway. Through the experiments for investigating various amino acids as putative precursors for the monacolin-K biosynthesis, it was found that production level of monacolin-K was remarkably increased when optimum amount of cysteine was supplemented into the production medium. We suggested that these phenomena might be related to the special roles of SAM (S-adenosyl methionine), a putative methyl group donor in the biosynthetic pathway of monacolin-K, demonstrating close interrelationship between SAM-synthesizing primary metabolism and monacolin-K synthesizing secondary metabolism. Namely, increase in the intracellular amount of SAM derived from the putative precursor, cysteine which was extracellularly supplemented into the production medium might contribute to the significant enhancement in the monacolin-K biosynthetic capability of the highly mutated producers. On the basis of these assumptions derived from the above fermentation results, we decided to construct efficient expression vectors harboring SAM synthetase gene (metK) cloned from A. nidulans, with the hope that increased intracellular level of SAM could lead to further enhancement in the monacolin-K production through overcoming a rate-limiting step associated with monacolin-K biosynthesis. Hence, in order to overcome the plausible rate-limiting step associated with monacolin-K biosynthesis by increasing intracellular level of SAM, we transformed the producer mutants with an efficient expression vector harboring gpdA promoter of the producer microorganism, and metK gene. Notably, from the resulting various transformants, we were able to screen a very high-yielding transformant which showed approximately 3.3 fold higher monacolin-K productivity than the parallel nontransformed mutants in shake flask cultures performed under the identical fermentation conditions.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1281-1293
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• 2021

The recent launch of the GOCI-II enables South Korea to have the world's first capability in deriving the ocean color data at geostationary satellite orbit for about 20 years. It is necessary to develop a consistent long-term ocean color time-series spanning GOCI to GOCI-II mission and improve the accuracy through validation using in situ data. To assess the GOCI-II's early mission performance, the objective of this study is to compare the GOCI-II Chlorophyll-a concentration (Chl-a), Colored Dissolved Organic Matter (CDOM), and remote sensing reflectances (R_rs) through comparison with the GOCI data. Overall, the distribution of GOCI-II Chl-a corresponds with that of the GOCI over the Yellow Sea, Korea Strait, and the Ulleung Basin. In particular, a smaller RMSE value (0.07) between GOCI and GOCI-II over the summer Ulleung Basin confirms the GOCI-II data's reliability. However, despite the excellent correlation, the GOCI-II tends to overestimate Chl-a than the GOCI over the Yellow Sea and Korea Strait. The similar over-estimation bias of the GOCI-II is also notable in CDOM. Whereas no significant bias or error is found for R_rs at 490 nm and 550 nm (RMSE~0), the underestimation of R_rs at 443 nm contributes to the overestimation of GOCI-II Chl-a and CDOM over the Yellow Sea and the Korea Strait. Also, we show over-estimation of GOCI-II R_rs at 660 nm relative to GOCI to cause a possible bias in Total suspended sediment. In conclusion, this study confirms the initial reliability of the GOCI-II ocean color products, and upcoming update of GOCI-II radiometric calibration will lessen the inconsistency between GOCI and GOCI-II ocean color products.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.548-556
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• 2021

This study was conducted to investigate the applicability of lignocellulosic fiber and coconut shell activated carbon (CSA) for the production of a particulate matter (PM)-reducing air-filter as raw materials to solve the environmental problems of non-woven fabrics. CSA had a good potential to use as a raw material of air-filter for reducing volatile organic compounds as well as noxious metals, and reduction capability of the CSA was 5 times higher than that of wood fiber. Natural adhesives formulated with proteinaceous wastes mostly were applied successfully to fabricate air-filters with the shape of fiberboard. The air-filter fabricated with the minimum target density of 200 kg/m³ and the maximum CSA-content of 40 wt% in fiberboard had a good manageable strength. However, the fiberboard filters was required to make vent-holes for improving an air-permeability of the filters. Size of the CSA particles was adjusted to greater than 2 mesh with the consideration of strength and formability of the fiberboard. Three-layers fiberboard that only wood fiber and the mixture of wood fiber and CSA were formed in the surface and middle layers, respectively, was determined to the optimal condition for the production of air-filters. In addition, traditional Korean paper handmade from mulberry trees (TKP) showed a good PM-reducing property as an air-filter. It is concluded that air-filtering set composed of fiberboard with vent-holes and TKP instead of conventional air-filters made with non-woven fabrics can be used as a filter for reducing the concentrations of PM, VOC and noxious metals existed in indoor and outdoor spaces.

• The Korean Journal of Archival Studies
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• no.21
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• pp.169-246
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• 2009

The national records management system of the Korean Government has been developed in a close relationship with changes in the administrative system. The national records management system established immediately after the establishment of the Korean Government, began to be reformed as a system with a new feature during the quick transition of the administrative system during the early 1960s. Particularly this new system holds an important meaning in that it began to cope with the mass production system of records and was established on the government level for the first time since the establishment of the government. Also this was a basic framework that defined the records management pattern of the Korean Government for the later 40 years. Therefore, this study aims to identify the origin and the meaning of the national records management system established during the early 1960s. At the time of establishing the government, the administrative system of the Korean Government was not completely free from the framework of the administrative system of the Chosen General Government. This was mainly because the Korean Government had no capability to renovate the administrative system. This was not an exception also for the national records management system. In other words, the forms and preparation methods of official document, an official document management process, and the classification and appraisal system used the records management system of the Chosen General Government without any alteration. Main factors that brought about the reform of the national records management system as well as the change in the Korean administrative system during the early 1960s, were being created in Korean society, starting from the mid 1950s. This resulted from the growth of Korean Army, public officers, and students of administrative science as being the intrinsic elites of Korean society through their respective experience of the US administration. In particular, the reform of the creation, classification, filing, transfer, and preservation system shown during the introduction of a scientific management system of the US Army in the Korean Army was a meaningful change given the historic developing process of Korean records management system history. This change had a decisive effect on the reform of the national records management system during the early 1960s. As the Korean Army, public officers, and students of administrative science, who had posted growth beginning in the mid-1950s, emerged as administrative elites during the early 1960s, the administrative system of the Korean Government brought about a change, which was different from the past in terms of its quality, and the modernization work of documentary administration pursued during the period, became extended to the reform of the national records management system. Then, the direction of reform was 'the efficient and effective control' over records based on scientific management, which was advanced through the medium of the work that accommodate the US office management system and a decimal filing system to Korean administrative circumstances. Consequently, Various official document forms, standards, and the gist of process were improved and standardized, and the appraisal system based on the function-based classification were unified on the government level by introducing a decimal filing system.

• Korean Journal of Acupuncture
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• v.35 no.4
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• pp.166-173
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• 2018

Objectives : Woogakseungmatang is a prescription medication mainly used to treat facial paralysis in Korean medicine. The purpose of this study is to investigate the effects of Woogakseungmatang on anti-inflammation and anti-oxidation. Methods : Woogakseungmatang was extracted using hot water. Cytotoxicity was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) method; nitric oxide(NO) production and Prostaglandin $E_2$ ($PGE_2$) production in RAW cells treated with Woogakseungmatang were investigated; and the cytokine changes associated with inflammation were examined. The antioxidant capacity of Woogakseungmatang was measured using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Results : RAW cells treated with Woogakseungmatang showed 90% cell viability at a $100-{\mu}g/ml$ concentration. NO production was decreased by 15% at a $100-{\mu}g/ml$ concentration. $PGE_2$ production was decreased by 18% at a $100-{\mu}g/ml$ concentration. Interleukin $1{\beta}$ ($IL-1{\beta}$), interleukin 6(IL-6), and tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$) were significantly reduced at $100{\mu}g/ml$ compared with those in the control group. The DPPH free radical scavenging capability was more than 50% at $100{\mu}g/ml$. Conclusions : Woogakseungmatang showed only a slight anti - inflammatory effect at $100{\mu}g/ml$ and it was difficult to confirm the concentration-dependent anti-inflammatory effect. Therefore, this study means to confirm the potential anti-inflammatory effects of Woogakseungmatang. Based on this research, more systematic and diverse studies should be conducted.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.1
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• pp.31-40
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• 2021

The hydrogen in nominally anhydrous mineral is known to be associated with lattice defects, but it also can exist in the form of water and hydroxyl groups on the large surface of the nanoscale particles. In this study, we investigate the effectiveness of 1H solid-state nuclear magnetic resonance (NMR) spectroscopy as a robust experimental method to quantify the hydrogen atomic environments of amorphous silica nanoparticles with varying relative humidity. Amorphous silica nanoparticles were packed into NMR rotors in a temperature-humidity controlled glove box, then stored in different atmospheric conditions with 25% and 70% relative humidity for 2~10 days until 1H NMR experiments, and a slight difference was observed in 1H NMR spectra. These results indicate that amount of hydrous species in the sample packed in the NMR rotor is rarely changed by the external atmosphere. The amount of hydrogen atom, especially the amount of physisorbed water may vary in the range of ~10% due to the temporal and spatial inhomogeneity of relative humidity in the glove box. The quantitative analysis of 1H NMR spectra shows that the amount of hydrogen atom in amorphous silica nanoparticles linearly increases as the relative humidity increases. These results imply that the sample sealing capability of the NMR rotor is sufficient to preserve the hydrous environments of samples, and is suitable for the quantitative measurement of water content of ultrafine nominally anhydrous minerals depending on the atmospheric relative humidity. We expect that 1H solid-state NMR method is suitable to investigate systematically the effect of surface area and crystallinity on the water content of diverse nano-sized nominally anhydrous minerals with varying relative humidity.

• Journal of the Daesoon Academy of Sciences
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• v.37
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• pp.329-355
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• 2021

The objective of this paper is to reveal that the formation of Deleuze's system is a result of a back flow of the 'ideal of pure reason' in Kant's system. I will try to seize upon the keyword in his main book, Difference and Repetition, and examine the aspect of mutual transformation between Deleuze's transcendental empiricism and Kant's transcendentalism. When analyzing Deleuze's system, most researchers tend to focus on anti-Hegelianism, but it is proper that Kant be adopted as the start when tracing the way of deployment directly. Fundamentally, Deleuze is different from Hegel in his approach to observing entire ground of thought. Even if Deleuze surely has the capability of becoming in the dialectical context, his systemic environment wherein dialectics is applied is different even at the onset. While Hegel follows the way of origin and copy or a system that begins from a preceding point of origin, Deleuze follows a way of copy and recopy or a system that begins without a point of origin. This characteristic of Deleuze's system originates directly from idealistic play. In fact, we can anticipate and identify in his book that he refers to Kant who accepted the tradition of empiricism. Therefore, the main contents of this paper is to present an overview of Kant's influence on Deleuze's system. While tracing ideas back to Kant's system, the cohabitation of empiricism and rationalism, which Kant felicitously revoiced, there emerges a definitude of world recognition. This occurs through cohabitation, and this is both deconstructed and integrated by Deleuze, and therein definitude is turned into a vision of prosperity. To the vision of prosperity that spans definitude to recognition, a philosopher has the right to select a philosophical system because selection methodology in philosophy is not a problem of legitimacy so much as the needs of the times. Deleuze's choice resulted in the opening of pandora's box in an abyss and secret contents have in turn risen sharply.