• Steel and Composite Structures
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• v.45 no.5
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• pp.749-766
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• 2022

This paper investigates the seismic performance of exposed RCFST column-base joints, in which the high-strength steel bars (USD 685) are set through the column and reinforced concrete foundation without any base plate and anchor bolts. Three specimens with different axial force ratios (n = 0, 0.25, and 0.5) were tested under cyclic loadings. Finite element analysis (FEA) models were validated in the basic indexes and failure mode. The hysteresis behavior of the exposed RCFST column-base joints was studied by the parametrical analysis including six parameters: width of column (D), width-thickness ratio (D/t), axial force ratio (n), shear-span ratio (L/D), steel tube strength (f_y) and concrete strength (f_c). The bending moment of the exposed RCFST column-base joint increased with D, f_y and f_c. But the D/t and L/D play a little effect on the bending capacity of the new column-base joint. Finally, the calculation formula is proposed to assess the bending moment capacities, and the accuracy and stability of the formula are verified.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.5
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• pp.757-765
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• 1999

In this paper, L-Type aperture coupled circular polarization patch antenna for mobile communication(IMT-2000, 1.9375 GHz), which is capable of being mounted in mobile unit, was designed and fabricated. This antenna is expanded to the $2\times2$ circular polarization array antenna for satellite mobile communications which are using the L-band frequency. The results are as followings : Returnloss 18.56 dB, beamwidth $60^{\circ}$, gain 7 dBd, axial ratio 0.9 dB in the case of single element and returnloss 28.43 dB, beamwidth $38^{\circ}$, gain 9.8dBd, axial ratio 1.5 dB in the case of $2\times2$ array, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1245-1251
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• 2013

The aim of this study is to identify characteristics of 2D:4D according to type of handedness. Data was collected from October, 4th, 2010 to April, 30th, 2012. After handedness assessment, 2nd and 4th finger length were measured by vernier calipers. This study showed remarkable gender difference of 2D:4D in left hand for left handers and right hand for right handers, However, there was no significant difference according to type of handedness in each gender. The correlation between left and right 2D:4D in males right handedness was higher than that of male left handedness, otherwise, in case of female, that of left handedness was higher than that of right handedness. The results of this study suggest that the 2D:4D of left handedness does not differ from that of right handedness, however, gender difference and correlation between left and right 2D:4D show different characteristics according to handedness.

• Journal of Korea Multimedia Society
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• v.12 no.4
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• pp.473-482
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• 2009

Reconstructed 3D data from computer vision includes necessarily a noise or an error. When these data goes through a mesh process, the different 3D mesh data from original shape comes to make by a noise or an error. This paper proposed the method that smooths a noise effectively by noise analysis in reconstructed 3D data. Because the proposed method is smooths a noise using the area ratio of the mesh, the pre-processing of unusable mesh is necessary in 3D mesh data. This study detects a peak noise and Gaussian noise using the ratio of 3D volume and 2D area of mesh and smooths the noise with respect of its characteristics. The experimental results using synthetic and real data demonstrated the efficacy and performance of proposed algorithm.

• Journal of Technology Innovation
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• v.17 no.1
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• pp.179-204
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• 2009

This paper aims to analyze the relationship between R&D outsourcing ratio (external R&D expenditures out of total R&D expenditures) and firm characteristics. Four hypotheses are tested using firm-level data with Tobit regression method. The major findings of this paper are as follows. First, firms with high technological capabilities, which are measured by R&D expenditures per sale and the number of patents per employee, rely more on R&D outsourcing. Nonetheless, firms that own R&D centers tend to rely less on external outsourcing of R&D. Second, firms with high managerial innovation capabilities, which is measured by the introduction of IT solutions, show higher R&D outsourcing ratio. Third, bigger firms are likely to spend more in external R&D than in internal R&D. This paper also discusses implications on R&D policy of Korea.

• Journal of electromagnetic engineering and science
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• v.7 no.2
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• pp.83-90
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• 2007

In this paper, the formulation of the protection ratio based upon a composite fade margin and availability is newly presented for the detailed planning of frequency coordination in the microwave relay system network, and computed results for co-channel and adjacent channel protection ratios are illustrated over an actual system with 6.2 GHz. It is shown that the protection ratio to assure a quality of service can be expressed in terms of the composite fade margin, noise-to-interference ratio, net filter discrimination, and system parameters. In addition, the net filter discrimination, depending upon the transmitter spectrum mask and the overall receiver filter characteristic, has been examined to investigate the effect of the adjacent channel protection ratio caused by the adjacent channel interference. Regarding simulated results for 6.2 GHz, 60 km, 64-QAM, and N/I=6 dB at the bit error rate of $10^{-6}$, composite fade margin and co-channel protection ratio yield 25.14 and 50.3 dB, respectively. Also, the net filter discrimination of 26.5 dB and the adjacent channel protection ratio of 23.8 dB are obtained at the first adjacent channel of 30 MHz. The proposed method provides some merits in view of a comprehensive and practical application with more detailed and various system parameters needed to access the criteria for making the proper frequency coordination.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.487-493
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• 2019

This study examines the ratio of R&D expenses in intangible assets for pharmaceutical companies, and determines whether these expenses affect the firm value among companies listed on the KOSDAQ. The research subjects included annual R&D expenses of 39 pharmaceutical companies listed on the KOSDAQ between 2011 and 2017. The survey was achieved via "Panel Data Model" with "Tobin Q" as an independent variable, and the ratio of R&D expenses in intangible as a dependent variable. Results of the study conclude that the ratio of R&D expenses in intangible assets of KOSDAQ pharmaceutical companies negatively influence the Tobin Q (Enterprise Value). A large proportion of intangible assets indicates increased R & D investment, and the operating profit is likely to be low due to the high debt ratio, thereby negatively impacting the enterprise value. This study further investigates whether the existing researches are based on researches that identify the total value of R & D expenditure. Results determine a significant relationship between enterprise value and R & D expenditure.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.2
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• pp.321-330
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• 2022

This study analyzed the difference between 2D image and 3D virtual clothing images based on stripe arrangement to obtain fundamental data for slim appearance. First, the slimming effect according to the three types of stripe ratio was examined. Subsequently, the slimming effects of seven types of one-piece dress designs according to the stripe location were analyzed. Subjective ranking was evaluated. The width items and radius of curvature were measured for the image's respective parts. Consequently, in 2D image and 3D virtual clothing images, the one with the narrowest stripe ratio was evaluated as the slimmest; however, the conditions for the slimming effect were different. In the seven one-piece dress designs, a difference was apparent in the ranking of the 2D image and 3D virtual clothing images. In the 3D virtual clothing image, arranging the stripes on the entire garment proved inefficient. The stripes were curved according to the curvature of the human body, creating an optical illusion that differed from that of the 2D image.

• Geomechanics and Engineering
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• v.8 no.6
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• pp.801-810
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• 2015

The ultimate pullout capacity under inclined dynamic loading is an important measure of the destruction degree of vertical screw piles (anchors) under dynamic actions. Based on the static and dynamic tests on two kinds of model screw piles, the ultimate bearing capacity was researched considering different distance-width ratio of blade (D/W) and preloading ratio. The results compared well with other experimental data available in the literature. This research reveals that D/W might determine the failure model of the piles (anchors), for example D/W = 3.14 or 5; a critical dynamic-static loading ratio (DSLR) existed in the experiments. The critical DSLR was reached under the conditions of 40%~60% preloading (D/W = 3.14) or 20%~40% preloading (D/W = 5), respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.215-218
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• 2003

We have developed a reflective 3.5" QVGA color TFT-LCD with high reflection within viewing angle. For this, We have introduced new pixel design and asymmetric reflector. Based on these technical concepts, we get a high aperture ratio of 93.5% and much higher reflection up to 64% with a 3.5" prototype panel.