• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.94-96
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• 2002

The $0.97MgTiO_3-0.03SrTiO_3$ ceramics with $B_2O_3$(10wt%) were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature by XRD and SEM. According to the X-ray diffraction patterns of the $0.97MgTiO_3-0.03SrTiO_3$ ceramics with $B_2O_3$(10wt%), the ilmenite $MgTiO_3$ and perovskite $SrTiO_3$ structures were coexisted and secondary phase $MgTi_2O_5$ were appeared. Increasing the sintering temperature. the grain size was increased. In the case of $0.97MgTiO_3-0.03SrTiO_3$ ceramics with $B_2O_3$(10wt%), dielectric constant, quality factor and temperature coefficient of resonant frequency were $13.52{\sim}18.13,\;32750{\sim}51736GHz$, $-15.78{\sim}25.64ppm/^{\circ}C$, respectively.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.11
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• pp.73-79
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• 2018

In this study, for the prediction of energy consumption in the ventilator, one of the components of the air conditioning system, the predicted results were analyzed and accurate by the change in the number of neurons and inputs. The input variables of the prediction model for the energy volume of the fan were the supply air flow rate, the exhaust air flow rate, and the output value was the energy consumption of the fan. A predictive model has been developed to study with the Levenbarg-Marquardt algorithm through 8760 sets of one-minute resolution. Comparison of actual energy use and forecast results showed a margin of error of less than 1% in all cases and utilization time of less than 3% with very high predictability. MBE was distributed with a learning period of 1.7% to 2.95% and a service period of 2.26% to 4.48% respectively, and the distribution rate of ${\pm}10%$ indicated by ASHRAE Guidelines 14 was high.8.

• Journal of Korea Game Society
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• v.21 no.6
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• pp.3-12
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• 2021

In this study, we verified the relationship of major variables that affect brand awareness, brand image and brand loyalty in the game industry. Six hypotheses for five variables were established and tested using K-BPI data. Distribution accessibility had the only significant effects on brand awareness, whereas marketing communication and distribution accessibility had significant effects on brand image. Only the brand image had a significant effect on brand loyalty. Brand communication to improve brand image and distribution to promote experiential marketing seem to be important.

• The Journal of the Acoustical Society of Korea
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• v.26 no.6
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• pp.227-234
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• 2007

This paper describes a transmission method based on a single carrier with frequency domain equalization (SC-FDE) scheme with cyclic prefix(CP). The SC-FDE has similar features with orthogonal frequency division multiplexing(OFDM). Similar to OFDM, a SC-FDE system is computationally efficient since equalization is reformed on a block of data in the frequency domain. Especially, it has the advantage of low sensitivity to nonlinear distortion compared to OFDM. In this paper, we design a SC-FDE receiver using decision-directed method, and present simulation results.

• Journal of Yeungnam Medical Science
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• v.27 no.2
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• pp.165-172
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• 2010

Primary thyroid lymphoma is a relatively rare thyroid tumor and usually a non-Hodgkin type. Its most common histologic type is the diffuse large B cell lymphoma followed by mucosa-associated lymphoid tissue(MALT). It is known to be frequently associated with autoimmune thyroiditis such as Hashimoto's thyroiditis. We report three cases of thyroid lymphoma at a single institution with are view of the literature.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.4
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• pp.18-29
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• 2015

The purposes of this research and development are as follows: first, to provide pleasant driving environments inside tunnels; second, to improve the current illumination environments lacking in diffusion luminance meters to meet tunnel lighting standards; and, third, to reduce the consumption of tunnel lighting energy accounting for approximately 65% of tunnel maintenance costs because of inadequate visual environments and tunnel operations. Further details are listed below. Firstly, an image luminance meter for tunnels that can implement the L20-method which is a tunnel luminance method that follows the international standards of CIE88, which was developed in order to improve and change the existing illumination-based tunnel lighting operation system to a luminance-based system. (The margin of error of below 5% according to the results of a test by an authorized agency and field test). Secondly, early illumination control is possible since the lighting control system that can be operated based on luminance enables interlocking control of the inside and outside of a tunnel using ethernet communication. Thirdly, guidelines for field application of the system are proposed. In addition, the luminance inducers of tunnels are found and the reflexibility of each facility that may reduce luminance of the boundaries is also proposed. Fourthly, as a result of a test bed, power consumption of luminance-based lighting operations decreased by 15.6% compared to illumination-based operations. Applying the feedback controls and maintenance factors of internal/external luminance meters, it reduced by 36.4%. Therefore, we became able to provide a luminance-based lighting operation system that complies with tunnel lighting design standards and provides a visual environment for drivers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.393-397
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• 2006

The study about Accelerated Life Test and analysis of failed data is increased in order to predict and evaluate reliability of products, according as the development cycle of products is reduced. Therefore, the decision of optimal distribution function about failed data for accurate analysis of failed data and test condition for Accelerated Life Test is very important. This paper compares Anderson-Darling method with Likelihood Function method for the decision of optimal distribution function about failed data. Anderson-Darling considers only failed data and Likelihood Function considers both failed data and life-stress relationship in decision of distribution function. In the results of comparison about two methods, we found that the distribution function chosen by each method is different and the life time predicted by each decided distribution function is different.

• Korean Journal of Pharmacognosy
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• v.32 no.4 s.127
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• pp.327-329
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• 2001

Cordyceps militaris (CM) has been used as a tonics in the traditional medicine. To investigate the anti-diabetic principle of CM, activity guided fractionation was conducted. Hot water extract of CM was fractionated into 3 parts: above 100,000(A), $100,000{\sim}20,000(B)$, below 20,000(C) in molecular weight using in membrane filter system. All fractions showed mild hypoglycemic activity in streptozotocin (STZ)-induced diabetic rats by oral administration (300 mg/kg). The fraction C which was most active among them was fractionated again into two parts, C-1 and C-2 by Sephadex LH 20 column chromatography. The fraction C-1 showed hypoglycemic activity but C-2 did not show activity compared with control in STZ mice. In glucose-fed hyperglycemic mice, fraction C, C-1 and C-2 also showed significant glucose lowering activity. Their decreasing rates of plasma glucose level after 1 hours administrations of fraction C, C-1 and C-2 were 24.5%, 29.3% and 22.0%, respectively (Tolbutamide: 48.4%). These results suggested that CM has both insulin like and insulin release promoting activity and could be developed as an antidiabetic agent.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.81-85
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• 2005

Pressure sensitive adhesive (PSA) was prepared by semi-batch emulsion polymerization of acryl monomers in the presence of reactive and non-reactive carboxylated polyurethane resin (PUR). Effects of the PUR type, its content, and crosslinker feeding method on the adhesive properties of the PSA was investigated. In this experiment, the PSA prepared with the reactive PUR showed better adhesive property then the PSA with the non-reactive PUR. Especially, peel strength of the PSA, where acetoacetoxy ethyl methacrylate and 1,6-hexane diamine as crosslinkers were introduced, was dramatically enhanced in severe humidity condition due to the interfacial crosslinking.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.480-484
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• 2000

A 10 years old female Poodle weighing 4.38 kg and a 10 years old female Maltese weighing 4.33kg were referred to veterinary leaching hospital of college of veterinary medicine, Konkuk uni-versity because of hematuria and severa anorexia. Preoperative hematological and srum chemical values revealed that counts of WBC were $78.4{\times}10^3$,/TEX>/ul in the Poodle and $21.6{\times}10^3$in the Maltese, concentrations of BUN 105 and 13 mg/dl, concentrations of creatinine 4.0 and 1.4 mg/dl, concentration of ALKP 542 U/L in the Poodle and concentration of ALF 37 U/L in the Maltese, respectively. Radiographic findings were observed radiopaque bilateral nephroliths in the Poodle and right renal cal- culus in the Maltese. Ultrasonographic findings were showed hyperechoic mass with severe acoustic shadowing, which were ]ocated in the center of both kidneys parenchyma in the Poodle and in right kidney in the Maltese. Bisectional nephrotomy in right kidney for removal of calculus, which had ,sin- gle stone and more large than splitted stones in lets kidney in the Poodle, was performed under isnf- lurane anesthesia in 100% $O_2$. The time from temporary occlusion of blood flow to suture of incisioned kidney after removal of renal calculi was elapsed 12 minutes. During operation and until 24hrs after operation was infusioned mannitol and tranexanic acid solution. There were normal urination with yellow color in the Poodle at 3 days after operation and in the Maltese at 1 day and good appetite after 7 days and 1 day after operation. At 7 days and 9 days after operation, hematolgoical and seam chemical values repealed that counts of WBC were $29.8{\times}10^3/u1 in the Poodle and 13.1 {\itmes}10^3$/ul in the Mal- tese, concentrations of BUN 13 and 10 mg/dl. concentrations of creatinine 1.3 and 1.1 mg/dl, con-centrations of ALT 34 and 97U/L, concentraion of AST 10 U/L in the Poodle, respectively, By ultra-sonographic view there was not observed hyperechoic mass and radippaque calculus in operated kid-ney in radiographic view.