• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.7
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• pp.85-92
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• 2010

In this paper, we consider the orthogonal frequency division multiplexing (OFDM) based transmission incoorperating with beam-switching and space-time coding. Specifically, we consider three configurations; (1) the beamforming technique, (2) the spatial diversity technique and (3) their combination and evaluate the performance in wireless personal area network (WPAN) environment. For the beam-forming technique, we consider the beam-switching which is performed at RF front-end with a pre-defined set of beams and for the space-time coding, we consider the Alamauti scheme with antenna selection. For the combined scheme, we divide the antennas used into two group to generate two independent beams and apply the two-antenna Alamauti scheme over the two beams. For these three configurations, performance is evaluated in terms of the SNR gain.

• Fashion & Textile Research Journal
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• v.17 no.6
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• pp.1013-1019
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• 2015

As the interest in leisure and health increases, the domestic outdoor wear industry becomes bigger. The waterproofness of fabrics does not ensure the waterproofness of garments because of the stitch holes during the sewing process even with the seam sealing tapes. Thus the water leakage often becomes a problem during the end use. Still companies use fabrics waterproofness data for garments marketing because they are simple to run the test, less expensive than the whole garment testing, and easy to achieve the quality control. In this study the rain tower system for evaluating the waterproofness of garments has been developed and the waterproofness of the selected waterproof and breathable garments in the market were tested. The rain tower was consisted of rain tower room, rainfall forming system and measurement system. Two different levels of rainfall can be simulated with this system(100l/m²/hr and 450l/m²/hr). Jackets in the market have been tested at two different rainfall conditions. The temperature and humidity data inside jackets didn't provide much information on the waterproofness at severe rainfall condition(450l/m²/hr, 1 hour). However, water leakage was detected on the cotton undershirt inside jacket. 5 out of 8 jackets passed the normal rainfall condition(100l/m²/hr, 30 minutes). The newly developed rain tower system was able to evaluate the waterproofness of the jacket seams. It is recommended the further study on the detailed test conditions for the end use of the waterproof and breathable garments.

• Nutrition Research and Practice
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• v.8 no.1
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• pp.3-10
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• 2014

The rapid increase in the prevalence of metabolic syndrome, which is associated with a state of elevated systemic oxidative stress and inflammation, is expected to cause future increases in the prevalence of diabetes and cardiovascular diseases. Oxidation of polyunsaturated fatty acids and sugars produces reactive carbonyl species, which, due to their electrophilic nature, react with the nucleophilic sites of certain amino acids. This leads to formation of protein adducts such as advanced glycoxidation/lipoxidation end products (AGEs/ALEs), resulting in cellular dysfunction. Therefore, an effective reactive carbonyl species and AGEs/ALEs sequestering agent may be able to prevent such cellular dysfunction. There is accumulating evidence that histidine containing dipeptides such as carnosine (${\beta}$-alanyl-L-histidine) and anserine (${\beta}$-alanyl-methyl-L-histidine) detoxify cytotoxic reactive carbonyls by forming unreactive adducts and are able to reverse glycated protein. In this review, 1) reaction mechanism of oxidative stress and certain chronic diseases, 2) interrelation between oxidative stress and inflammation, 3) effective reactive carbonyl species and AGEs/ALEs sequestering actions of histidine-dipeptides and their metabolism, 4) effects of carnosinase encoding gene on the effectiveness of histidine-dipeptides, and 5) protective effects of histidine-dipeptides against progression of metabolic syndrome are discussed. Overall, this review highlights the potential beneficial effects of histidine-dipeptides against metabolic syndrome. Randomized controlled human studies may provide essential information regarding whether histidine-dipeptides attenuate metabolic syndrome in humans.

• Resources Recycling
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• v.12 no.4
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• pp.58-64
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• 2003

A study on the preparation of RDF with ASR materials from shredder line of end-of-life vehicles has been peformed by using hot molding method. ASR materials used in the work were plastics, fibers and sponge which were cut by less than 10 mm in size prior to hot molding and 40, 60 and 80 mm mold in diameter were employed for RDF forming. It was found that heating temperature, heating time and mixing ratio of materials played an important role in the hot molding of ASR materials. Density of RDF samples Prepared in the work was in the range of 0.5∼0.9gr/ml depending on the hot molding conditions and it was decreased with increase in the content of sponge. Breaking strength of RDF samples was observed to 0.8∼3.0MPa and it was also increased with increase in density of RDF samples. Finally, when heating temperature was elevated, density of RDF was increased due to Increase in molten part of ASR materials which resulted in the enhancement of breaking strength of RDF.

• Journal of the Korean institute of surface engineering
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• v.4 no.1
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• pp.5-15
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• 1971

"Rapid Determination of Boric Acid in Nickel Plating Solution" by the addition of Na$_2$C$_2$O$_4$ and thus preventing the precipitation of i(OH)$_2$ during titiration , has previously been reported. In this paper, the exact amount of glycerine and the complexing possibility of oxalate with nickel has been determined by measn of conductivity titrations. This experimental work has been supported by the mathematical application of the Debye-Huckel and mass action equitions as well as statistical analysis. The results were ; (1) Fro determining boric acid in nickel plating solution, 20 ml of 400ml/ι glycerine was sufficient, since 97% of the H$_3$BO$_3$ was dissoicated by this addition. (2) In the absence of Na$_2$C$_2$O$_4$ the continious precipitation of Ni(OH)$_2$ during titration with NaOH even past end -point for boric acid determination resulted in considerable anlaytical error. (3) In the presence of Na$_2$C$_2$O$_4$ during titration , Ni++ combined with C$_2$O$_4$-to form NiC$_2$O$_4$. The solution with this precititate of very fine, colloidal , trantsparent particles, remained quite clear for approximately 2 hours. Therefore it was shown that the presence of Na$_2$C$_2$O$_4$ prevents the formation of gross Ni(OH)$_2$ precititation by forming NiC$_2$O$_4$ instead of a complex salt with Ni++ , which did not interfere with the visible determination of the end point for boric acid with NaOH titation. This observous may be interpreted in the light of the previously published solubility ratio for NiC$_2$O$_4$ and Ni(OH)$_2$, 0.3mg/100g H$_2$O(25$^{\circ}C$), respectively. Precipitation of the less soluble , albeit transparent salt, NiC$_2$O$_4$ precluded therefore the precipitation of the Ni(OH)$_2$ salt.

• Journal of Information Technology Applications and Management
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• v.24 no.4
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• pp.41-55
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• 2017

Industrial Revolution is a concept and a development that has fundamentally changed our society and economy. Industry 4.0 focuses on the end-to-end digitization of all physical assets and integration into digital ecosystems with value chain partners. At present, we find ourselves at the beginning of this fourth stage, which is characterized by so-called "Cyber-Physical Systems". These systems are a consequence of the far-reaching integration of production, sustainability and customer-satisfaction forming the basis of intelligent network systems and processes. If South Korea ran toward global ICT with the advent of the Fourth Industrial Revolution, North Korea has adhered to a unique Juche science and technology. ICT in South Korea and North Korea seems very difficult to find common interests. However, as seen in the Internet and intranets, information and communication technology can find similarities in many areas than in general science and technology. There are many differences not only in the level of ICT and science and technology but also in the direction. And IT terminology and all technologies are also different. What are we preparing for the unification of North and South Korea? If we look at the science and technology sector at present, there seems to be no systematic preparation by the government. South Korea and North Korea need to be prepared for science and technology cooperation. First, it is necessary to understand the exact situation of North Korea's science and technology. In this study, we will perform research to establish mid and long term plans for revitalization of ICT cooperation between the two Koreas. In this study, we will determine the extent to which the two Koreas utilize ICT based on available ICT capabilities and technologies. To do this, we conducted research to measure and evaluate the ICT development index of North Korea using ICT international index.

• International Journal of Oral Biology
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• v.36 no.2
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• pp.51-57
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• 2011

Runx2 and Osterix, the transcription factors for osteoblast differentiation, are known as fundamental factors to regulate the development of calcified tissues. However, the biological functions of these factors in the development of the periodontal tissues remain unclear. In this study, we investigated the distribution of Runx2 and Osterix during periodontal tissue development of the mice. Mandibles from 14-day-old mice were prepared for paraffin section. Serial sections of the mandible containing $1^{st}$ molar tooth germs were obtained as a thickness of $7\;{\mu}m$. Some sections were stained with hematoxylin and eosin. Others were used for immunohistochemistry for PCNA, Runx2, and Osterix. Epithelial cells in growing end of Hertwig's epithelial root sheath (HERS) and mesenchymal cells adjacent to the growing end of HERS expressed PCNA. Undifferentiated mesenchymal cells and hard tissue forming cells like cementoblasts and osteoblasts in early stage of differentiation expressed Runx2. Fully differentiated cementoblasts and osteoblasts secreting matrix proteins expressed Osterix. However, the cells terminated the matrix formation did not express Osterix. Periodontal ligament cells expressed Runx2 and Osterix. Pulp cells expressed Runx2 only. These results suggest that Runx2 and Osterix might regulate the differentiation of cementoblasts in the same manner as osteoblasts. Runx2 might participate in the process of cementoblast differentiation in early stage, whether Osterix might regulate the maturation and matrix synthesis of the cells.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.42-47
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• 1961

A titration of a small amount of iron with standard potassium ferrocyanide using potassium thiocyanate as indicator has been studied. A sample solution containing $0.1{\sim}1.0$ mg. $Fe^{3+}$ in 60 ml. is pipeted into 100 ml. Erlenmyer flask and the pH of the solution is adjusted to $1.5{\sim}3.0$ with 0.1 N or 1 N $HNO_3$ and $NH_4OH.$ To this solution one ml. of 1 M KCNS solution as indicator is added. The solution colored by iron thiocyanate complex is titrated with 1/200 M or 1/400 M standard solution of potassium ferrocyanide from a 5 ml. micro-buret. Near the end point, when the color of sample changes from deep red to green, about 20 ml. of ether is added and shake the flask vigorously. The red color is extracted to the ether layer. To settle the ether layer a few drops of ethanol is added and then standard solution is added dropwise and shake vigorously. The end point is reached when the color of the ether layer disappears owing to the quantitative formation of $Fe_4[Fe(CN)_6]_3.$ In this titration, 0.lmg. of $Fe^{3+}$ can be determined within 1.0% of titration error, provided the following optimum conditions, i.e., pH $1.5{\sim}3.0$, final concentration of KCNS indicator; $0.01{\sim}0.02M$, at room temperature. The titration found to be interfered by the presence of slightly soluble salts, stable complex forming ions and the ions which would be reduced by ferrocyanide or oxidized by ferric ion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.139-140
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• 2017

This technology employs a method of forming a single-ply PLUS waterproofing sheet layer comprised of applying a single-ply synthetic polymer layer on a vibrating structure (steel frame, RC) or an inclined surface by using a T joint lap-filling coil and an embedded metal coated sheet. The T - joint reinforcing lap-filling coil was used to block the ingress channel of the rainwater by applying the material in the vulnerable area where the three sides of the waterproof sheet overlapped. Conventional waterproofing techniques have a problem in that the waterproof sheet is pierced because the end portion of the waterproof sheet applied to the vertical portion is fixed by a nail, and the sealant applied to the end portion of the sheet cannot easily secure long-term waterproof durability due to the influence of the external environment. Therefore, the developed technology secured the waterproof durability against the vertical part by using the embedded metal sheet. In addition, automatic hot-air fusing is used to improve the quality of waterproof construction and point fixation method using fixed hardware. This is a technology that is not significantly restricted in the high degradation level regions of domestic waterproof construction environments in Korea such as low-temperature environment, wet floor.

• Korean Journal of Adult Nursing
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• v.22 no.6
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• pp.663-675
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• 2010

Purpose: The purpose of this study was to explore the life experiences of patients with a severe Chronic Obstructive Pulmonary Disease (COPD). Methods: The data were collected through in-depth interviews of six patients suffering from severe COPD. The interviewed data were audio-recorded and transcribed verbatim and checked for accuracy. The Giorgi method of phenomenology was used for analyzing data. Results: Eight themes forming the, units of meaning, were: Repeated and Unpredictable Suffering of Dyspnea, Confidence Loss/Exhaustion Life due to non-efficient breathing, Gradually Deprived Liberty, Absolute Being to Sustaining my life, Source of Burden but Significant Person I am in the Family, Endless Tug-of-War-Capability/Endeavor to Breath, Longing for my Life, and Dead-end of breathing. Conclusion: The study results provide an in-depth understanding of life experiences of patients suffering from severe COPD. The findings will be useful to nurses caring for this population.