• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.487-489
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• 2018

This paper presents chaotic Lorenz system implementation for secure data communication applications. In this work chaotic signal is generated by a PIC18F family based microcontroller, XC8 compilers have been utilized for the compilation of C code of microcontroller program. For simulation work Matlab and Proteus platforms were utilized and finally, chaotic time waveforms, 2D and 3D chaotic attractor were obtained and secure communication waveforms were achieved successfully.

• 한국전산유체공학회:학술대회논문집
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• 2002.10a
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• pp.150-155
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• 2002

A commercial CFD code is applied to analyze the 3-D viscous flow field within vertical multi-stage centrifugal pump including impeller with 6 blades and guide vane with 11 blades and is performed by changing flow rate from 10 to $26m^3/h$ at the constant 3500rpm. The purpose of this 3-D numerical simulation is not only to confirm how much the effect of three kinds of blade inlet breadth (11mm, 11.5mm, 12mm) of impeller has influence on the performance of vertical multi-stage pump but also to make clear the cause about performance difference at the exit side of impeller and guide vane. The vertical multi-stage pump consisit of the impeller, guide, vane and cylinder. The grid of numerical analysis used to the vertical multi-stage pump is 18,000, 45,000, and 100000 cells in case of the impeller, guide vane, cylinder and total grid is 730,000 cells. The characteristics such as total pressure coefficient, total head, shaft horse power, power efficiency at the exit side of impeller and guide vane, discharge coefficient are represented according to flow rage changing.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.341-342
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• 2007

The IRFPA (InfraRed Focal Plane Array) ROIC (ReadOut Integrated Circuit) was designed in folded-cascode Op-Amp using $0.35{\mu}m$ CMOS technology. As the folded-cascode has high open-loop voltage gain and fast settling time, that used in many analog circuit designs. In this paper, folded-cascode Op-Amp for ROIC of the $32{\times}32$ IRFPA has been designed. HSPICE simulation results are unit gain bandwidth of 13.0MHz, 90.6 dB open loop gain, 8 V/${\mu}m$ slew rate, 600 ns settling time and $66^{\circ}$ phase margin.

• Journal of Korean Academy of Rural Health Nursing
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• v.5 no.1
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• pp.33-39
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• 2010

Purpose: This study was done to identify change in self-concept of smoking experience in middle school students. Method: The study was a longitudinal survey design and used only the responses on self-concept and smoking state from the data of the Korea Youth Panel Survey (KYPS). The sample for this study consisted of 3,449 middle school students and the data were collected over a two-year period (2003-2004). Results: Self-esteem scores for the first and second year were significantly higher and self-stigma and aggression scores were significantly lower in the non-smoking maintenance group. There was a significant increase in self-esteem scores for students in second year who quit smoking compared to those in first year. There was a significant decrease in scores for attachment to surrounding people and emotional sense of control in second year students compared to those first year for students in the non-smoking maintenance group and the group that quit smoking. Self-intimacy scores were significantly lower in the smoking maintenance group. There was a significant increase in sex-role identity scores in second year students compared to those in first year for students in the group who newly started smoking. Conclusion: Findings from this study can contribute to designing appropriate smoking prevention strategies to improve self-constructs related smoking experiences in adolescents.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.2
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• pp.224-230
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• 2012

Thermal batteries have excellent mechanical robustness, reliability, and long shelf life. Due to these characteristics as well as their unique activation mechanism, thermal batteries are widely adopted as military power sources. Li(Si)/$FeS_2$ thermal batteries, which are used mostly in these days, use LiCl-KCl and LiBr-LiCl-LiF as molten salt electrolyte. However, it is known that Li(Si)/$FeS_2$ thermal batteries have high internal resistance. Especially, $FeS_2$ cathode accounts for the greater part of internal resistance in unit cell. Many efforts have been put into to decrease the internal resistance of thermal batteries, which result in the development of new electrode material and new electrode manufacturing processes. But the applications of these new materials and processes are in some cases very expensive and need complicated additional processes. In this study, internal resistance study was conducted by adding carbon black and carbon nano-tube, which has high electron conductivity, into the $FeS_2$ cathode. As a results, it was found that the decrease of internal resistance of $FeS_2$ cathode by the addition of carbon black and carbon nano-tube.

• Journal of Plant Biology
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• v.39 no.4
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• pp.273-278
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• 1996

Arabidopsis mutants deficient in flavonoid and sinapate ester (tt4 and fah1-7, respectively) were evaluated in vivo and in vitro to study the possible role of flavonoid compounds in pollen tube growth. In vivo, we investigated pollen tube growth in the pistils of the mutants and wild type(Ler). The growth of pollen tubes was significantly different among the three genotypes. In the fal1-7 pistils, the tubes grew to a greater length relative to those of the wild type or tt4. To examine in vitro pollen tube growth, a solid medium was devised for pollen germination and subsequent growth. In vitro, the identical result was obtained; fahl-7 pollens developed the longest tubes and elongated most rapidly. Therefore, the growth response of pollen tubes to phenolic compounds was examined by adding quercetin or sinapate ester in various concentrations to the media. Quercetin enhanced both germination rate and tube growth in the pollens of the mutants and the wild type, especially in tt4. In contrast, sinapate ester inhibits pollen germination and pollen tube growth in three genotypes. These results suggest that flavonoids and related phenolic compounds have physiological role in the plant reproductive system.

• Journal of Veterinary Clinics
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• v.38 no.5
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• pp.249-253
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• 2021

We describe the case of a Jindo dog that presented with a 2-month history of an abscess-like mass on the skin of the left hip. The patient was initially diagnosed with a suspected insect bite and was treated with a topical dressing. After observing no improvements, surgical debridement was done to remove the abscess. Nine days after surgery, the patient started showing severe anorexia, vomiting, lethargy, and oliguria. Azotemia was detected, and the patient was diagnosed with acute kidney injury. Ultrasonography depicted an abdominal mass (4.6 × 7.5 cm) in the right ureter, and severe hydronephrosis in the right kidney. The patient was euthanatized. Results of the necropsy, histopathologic examination, and immunohistochemistry for tumor cells, confirmed that the patient had developed hydronephrosis and disseminated histiocytic sarcoma which had metastasized to the lungs. To the best of our knowledge, this is the first report of acute renal failure produced by ureter invasion and urinary tract obstruction resulting from the abdominal mass of disseminated histiocytic sarcoma in dogs.

• Journal of Korea Society of Waste Management
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• v.34 no.2
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• pp.140-147
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• 2017

This study was conducted to evaluate the effects of physical characteristics. Twelve specific odorous compounds and various sources of bacteria were tested via treatment of food waste using an ultra-thermophilic aerobic composting process. Food waste was mixed with seed material and operated for 47 days. During composting, the temperature was maintained at $80-90^{\circ}C$. The variations in $O_2$, $CO_2$ and $NH_3$ production suggested typical microorganism-driven organic decomposition patterns. After composting, the concentrations of 12 specific odorous compounds other than ammonia did not exceed the allowable exhaust limits for odor. After composting, thermophiles represented 50% of all bacteria. After composting, the percentage of thermophile bacterial increased by 15%. Therefore, both stable composting operation and economic benefit can be expected when an ultra-thermophilic composting process is applied to food waste.

• The Journal of Korean Medicine
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• v.43 no.1
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• pp.42-59
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• 2022

Objectives: This study was done to establish the anatomical meaning of the term 'Geun(筋)'. Methods: Through analysis of 《HwangJeNaeGyeong(黃帝內經)》, the meaning of 'Geun(筋)', 'GeunMag(筋膜)', 'Yug(肉)', and 'Gi(肌)' were established. Based on analysis, the anatomical meaning of the 'Meridian-muscle(經筋)' was studied by comparing it with anatomy. Results & Conclusions: 'Gyeong(經)' is recognized as a metaphysical expression and "Geun(筋)" means myofascia in anatomy. The concept of 'Geun(筋)' includes the epimysium and perimysium, as well as tendons and ligaments, which are extensions of these. 'Fascia', refers to the fascia of the whole body, and also appertain to 'Geun(筋)'. 'Yug(肉)' means endomysium, muscle fiber, and adipose tissue and layer. The word 'GeunMag(筋膜)' used in the 《HwangJeNaeGyeong(黃帝內經)》 means anatomically a 'tendon'. Therefore, 'Muscle' should be translated as 'GeunYug(筋肉)' in Traditional medicine. 'Meridian-muscle(經筋)' can be defined as the longitudinal muscle and fascia system, which is the basis of whole body encompassing dynamics.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.308-311
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• 2012

A wide range of possible hazards existing in thermal batteries are mainly caused by thermal runaway, which results in overheating or explosion in extreme case. Battery separators ensure the separation between two electrodes and the retention of ion-conductive electrolytes. Thermal runaways in thermal batteries can be significantly reduced by the adoption of these separators. The high operating temperature and the violent reactivity in thermal batteries, however, have limited the introduction of conventional separators. As a substitute for separators, MgO powders have been mostly used as a binder to hold molten salt electrolyte. During recent decades the fabrication technology of ceramic fiber, which has excellent mechanical strength and chemical stability, has undergone significant improvement. In this study we adopted wet-laid nonwoven paper making method instead of the electrospinning method which is costly and troublesome to produce in volume. Polymeric precursor can readily be coated on the surface of wet-laid ceramic paper, and be formed into ceramic film after heat treatment. The mechanical strength and the thermo-chemical stability as well as the wetting behaviors of ceramic separators with various molten salts were investigated to be applicable to thermal batteries. Due to their excellent chemical, mechanical, and electrical properties, wet-laid nonwoven separators made from ceramic fibers have revealed positive possibility as new separators for thermal batteries which operate at high temperature with no conspicuous sign of a short circuit and corrosion.