• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.41-52
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• 2011

This study was carried out to investigate the effect of energy saving and sound insulation of building materials mixed with charcoal. To investigate the functionality of building based on the difference of construction materials, three different experimental buildings were constructed. They were buildings built with the conventional construction materials (A), the charcoal construction materials (B), and the charcoal-sericite construction materials (C). The study showed that energy consumption could be reduced approximately 9.5% and 14.5% by replacing A with B and C, respectively. Especially, it is revealed that the lower outdoor temperature was, the higher energy saving effect was. Also, after shutoff the boiler switch the decrease rate of room temperature of the one using B was lower than those of others using A and C so that the room temperature at the building using B was higher by $3.5{\sim}4.2^{\circ}C$ in the 1 meter air above the ground and by $4.4{\sim}5.4^{\circ}C$ on the floor surface after 12 hours passed. In the building noise test the heavy-and light-weight impact sound of the plate, represented by criterion of noise between floors in multi-story building, tended to decrease in the test sample containing charcoal.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.12
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• pp.41-49
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• 2004

Increase of internet users and new types of applied traffics, have led to demand for more bandwidth for each application. Hence, the amount of internet traffic has risen sharply and it has demanded to use limited resources, such as wavelength and bandwidth, more effectively. These kind of needs can be satisfied with OXC(Optical cross-connects) based on GMPLS that carry out IP packet switching and wavelength switching at the same time and Provide very wide bandwidth. In RSVP-TE signaling of GMPLS studied by IETF. every lambda router in core network should be able to convert wavelength. So, lots of wavelength converters and needed and building and managing cost is high. Another problem is that optimized traffic is limited. In this paper We suggest strengthened GMPLS RSVP-TE signaling algorithm for a better lightpath setup. When setup signaling is blocked suggested algorithm does not send PathErr message to Edge Router, but looks for nearest lambda router which can convert wavelength and carry out setup signaling from that node. Such algorithm can reduce the chance of blocked lightpath setup signaling and provide effective arrangement of lambda router in core network by calculating proper number of wavelength converter.

• Journal of The Korean Association For Science Education
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• v.32 no.2
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• pp.388-401
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• 2012

This study attempted to propose a theoretical model for STEAM education, entitled to the Ewha-STEAM education model, which could provide more concrete guidelines for science educators and curriculum developers to execute STEAM ideas. We identified key knowledge and key competencies to nurture future creative/convergent human resources. Key knowledge included an understanding of core ideas cutting across traditional disciplinary boundaries as well as the nature of different disciplines. And additionally, key competencies implied such abilities as to explore the scientific world, to resolve problems, and to communicate and collaborate with others. We also added creativity and character as an essential part of key competencies. In order to provide more specific guidelines when developing, implementing, and evaluating STEAM curriculum, we suggested three elements of convergence to consider: 1) unit of convergence (i.e. concept/skills, problem/phenomenon, activity), 2) degree of convergence (i.e. multi-disciplinary, inter-disciplinary, extra-disciplinary), and 3) context of convergence (i.e. personal, societal, global). It is expected that the Ewha-STEAM education model would contribute towards diverse education communities understanding the direction of STEAM education and its educational potentials.

• Journal of Korean Society of Forest Science
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• v.81 no.1
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• pp.21-29
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• 1992

This study was conducted to provide basic information for deciding silvicultural system appropriate to a natural mixed stand in Jindong-Ri. For this, the stand structure such as DBH distribution, height distribution, and volume per DBH class were analyzed and the possibility of selection cutting as a silvicultural system was discussed. The DBH structure of the stand has reverse J-shaped diameter distribution which is typical in a selection cutting stand. The possibility of selection cutting is also accepted in the height structure by showing multi-storied height distribution of the stand. On the other hand, volume structure per DBH class did not show the mature stand of selection cutting due mainly to the lack of number of trees at 30cm DBH class and above. It seems that the unclear part of stand structure should be solved by further studies. Also, the rate of increment for DBH and volume should be estimated to predict the future stand structure.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1085-1090
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• 2002

Genetic parameters for birth weights (BWT), calving ease scores observed from calves born by heifers (CEH), and calving ease scores observed from calves born by cows (CEC) were estimated using Bayesian methodology with Gibbs sampling in different threshold animal models. Data consisted of 77,458 records for calving ease scores and birth weights in Gelbvieh cattle. Gibbs samplers were used to obtain the parameters of interest for the categorical traits in two univariate threshold animal models, a bivariate threshold animal model, and a three-trait linear-threshold animal model. Samples of heritabilities and genetic correlations were calculated from the posterior means of dispersion parameters. In a univariate threshold animal model with CEH (model 1), the posterior means of heritabilities for calving ease was 0.35 for direct genetic effects and 0.18 for maternal genetic effects. In the other univariate threshold model with CEC (model 2), the posterior means of heritabilities of CEC was 0.28 for direct genetic effects and 0.18 for maternal genetic effects. In a bivariate threshold model with CEH and CEC (model 3), heritability estimates were similar to those in unvariate threshold models. In this model, genetic correlation between heifer calving ease and cow calving ease was 0.89 and 0.87 for direct genetic effect and maternal genetic effects, respectively. In a three-trait animal model, which contained two categorical traits (CEH and CEC) and one continuous trait (BWT) (model 4), heritability estimates of CEH and CEC for direct (maternal) genetic effects were 0.40 (0.23) and 0.23 (0.13), respectively. In this model, genetic correlation estimates between CEH and CEC were 0.89 and 0.66 for direct genetic effects and maternal effects, respectively. These estimates were greater than estimates between BWT and CEH (0.82 and 0.34) or BWT and CEC (0.85 and 0.26). This result indicates that CEH and CEC should be high correlated rather than estimates between calving ease and birth weight. Genetic correlation estimates between direct genetic effects and maternal effects were -0.29, -0.31 and 0.15 for BWT, CEH and CEC, respectively. Correlation for permanent environmental effects between BWT and CEC was -0.83 in model 4. This study can provide genetic evaluation for calving ease with other continuous traits jointly with assuming that calving ease from first calving was a same trait to calving ease from later parities calving. Further researches for reliability of dispersion parameters would be needed even if the more correlated traits would be concerned in the model, the higher reliability could be obtained, especially on threshold model with property that categorical traits have little information.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.7
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• pp.663-670
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• 2016

This paper introduces the concept of the computer-aided engineering(CAE) design method for a bypass valve in a system that is used for the safe lifting of mineral resources in deep-seabed mining. Although the bypass valve has a simple mechanism, its design is very difficult because of various influencing factors. This equipment, which has a complex design process, should be developed by CAE-based design method. The method can perform the design, design verification, and virtual experiment at the same time. In this study, the CAE-based method for the design of the bypass valve has been developed using fluid dynamics, multi-body dynamics, and optimization method.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.2
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• pp.70-75
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• 2014

Recently, the demand for high-integrated, low-powered, and high-powered SoC design has been increasing due to the multi-functionality and the miniaturization of digital devices and the high capacity of service informations. With the rapid evolution of the system, the required hardware performances have become diversified, the FPGA system has been increasingly adopted for the rapid verification, and SoC system using the FPGA and the ARM core for control has been growingly chosen. While the AXI bus is used in these kinds of systems in various ways, it is traditionally designed with AXI slave structure. In slave structure, there are problems with the CPU resources because CPU is continually involved in the data transfer and can't be used in other jobs, and with the decreased transmission efficiency because the time not used of AXI bus beomes longer. In this paper, an efficient AXI master interface is proposed to solve this problem. The simulation results show that the proposed system achieves reductions in the consumption clock by an average of 51.99% and in the slice by 31% and that the maximum operating frequency is increased to 107.84MHz by about 140%.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.225-232
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• 2020

The underlaying communication scheme in 5G cellular network is a very promising resource sharing scheme, and it is an effective scheme for improving service performance of 5G and reducing communication load between a cellular link and a device to device (D2D) link. This paper proposes the algorithm to minimize the resource interference that occurs when performing 5G-based multi-class service on gNB(gNodeB) and the cooperative priority-based resource allocation scheduling scheme (CPRAS) to maximize 5G communication service according to the analyzed control conditions of interference. The proposed CPRAS optimizes communication resources for each device, and it optimizes resource allocation according to the service request required for 5G communication and the current state of the network. In addition, the proposed scheme provides a function to guarantee giga-class service by minimizing resource interference between a cellular link and a D2D link in gNB. The simulation results show that the proposed scheme is better system performance than the Pure cellular and Force cellular schemes. In particular, the higher the priority and the higher the cooperative relationship between UE(User Equipment), the proposed scheme shows the more effective control of the resource interference.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.2
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• pp.151-159
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• 2004

The diversity, expansion of human activity and rapid urbanization make modem society to faced with problems like damage of nature and drain of natural resources. Under these circumstances rapid and accurate change detection techniques, which can detect wide range utilization changes, are needed for efficient management and utilization plan of national territory. In this study to perform change detection from remote sensing images, space analysis technique contained in Geographic Information System is applied. And from this technique, the software. that can execute new change detection algorithm, query, inquiry and analysis, is produced. This software is on the basis of graphic user interface and has many functions such as format conversion, grid calculation, statistical processing, display and reference. In this study, simultaneously change detection for multi-temporal satellite images can be performed and integrated one change image about four different periods was produced. Further more software user can acquire land cover change information for an specific area through querying and questioning about yearly changes. Finally making of every application module for change detection into one window based visual basic program, can be produced user convenience and automatic performances.

• Membrane Journal
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• v.23 no.1
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• pp.1-11
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• 2013

Poly(ether imide) (PEI)-poly(dimethylsioxane) (PDMS) composite membranes and their modules were prepared, which are capable of selective $CO_2$ separation from the mixture gas. The gas flow rate, concentration, recovery ratio of $H_2$ and removal ratio of $CO_2$ outflowing by stage-cut were characterized at $25^{\circ}C$ and the constant pressure. In addition, to increase the recovery ratio of $H_2$, one stage, two stage series connection, and three stages series + parallel connection tests were carried out. When the stage-cut was 0.32 for the three stages connection operation, the concentration $H_2$ of the produced gas and the recovery ratio of $H_2$ was 97% and 85%, respectively. And also the removal ratio of $CO_2$ was 90% was obtained and the recycled gas concentration was similar with that of the feed gases.