• International Journal of High-Rise Buildings
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• v.6 no.1
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• pp.83-89
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• 2017

Due to the time-dependent properties of materials, structures, and loads, accurate time-dependent effects analysis and precise construction controls are very significant for rational analysis and design and saving project cost. Elevation control is an important part of the time-dependent construction control in supertall structures. Since supertall structures have numerous floors, heavy loads, long construction times, demanding processes, and are typically located in the soft coastal soil areas, both the time-dependent features of superstructure and settlement are very obvious. By using the time-dependent coupling effect analysis method, this paper compares Shanghai Tower's vertical deformation calculation and elevation control scheme, considering foundation differential settlement. The results show that the foundation differential settlement cannot be ignored in vertical deformation calculations and elevation control for supertall structures. The impact of foundation differential settlement for elevation compensation and pre-adjustment length can be divided into direct and indirect effects. Meanwhile, in the engineering practice of elevation control for supertall structures, it is recommended to adopt the multi-level elevation control method with relative elevation control and design elevation control, without considering the overall settlement in the construction process.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.245-251
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• 2016

Despite the exponential throughput improvement in mobile communications systems, their ability to satisfy requirements of state-of-the-art and future applications of advanced metering infrastructure (AMI) is still under investigation. Challenges are mainly due to the inadequacy of third generation partnership project (3GPP) networks to support large amounts of devices simultaneously, while the number of AMI end-devices and the frequency of their data transmission increase with new AMI-based applications. In this introductory survey, innovative and future AMI applications and their communication requirements are first reviewed. Then, we identify challenges of 3GPP long term evolution (LTE) in enabling future AMI applications. More importantly, the latest improvements to LTE-A standard release 12 and 13 are reviewed and analyzed with regards to their potential to improve the quality of LTE-enabled AMI. It is found that 3GPP enhancements on machine type communications (MTC) standards will significantly enhance AMI communications. Beyond MTC specifications, non-MTC-specific enhancements such as carrier aggregation and multi-connectivity for user equipment will also contribute greatly to improving reliability and availability of AMI devices. The paper's focus is towards improved backhaul support for innovative and future AMI applications, beyond traditional automatic meter reading.

• The Journal of the Korea Contents Association
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• v.6 no.11
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• pp.225-234
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• 2006

In this paper, we design a combined security processor, ECC, MD-5, and AES, as a SIP for cryptography of securing contents. Each SIP is modeled and designed in VHDL and implemented as a reusable macro through logic synthesis, simulation and FPGA verification. To communicate with an ARM9 core, we design a BFM(Bus Functional Model) according to AMBA AHB specification. The combined security SIP for a platform-based SoC is implemented by integrating ECC, AES and MD-5 using the design kit including the ARM9 RISC core, one million-gate FPGA. Finally, it is fabricated into a MPW chip using Magna chip $0.25{\mu}m(4.7mm{\times}4.7mm$) CMOS technology.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.10
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• pp.879-887
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• 2003

Buildings with heating and cooling systems have been increased, since the requirement of thermal comfort for residents is grown. Heating and cooling systems, have been changed from two separate systems to one multi-function system which includes both heating and cooling. Especially, heat pump heating and cooling system has been adopted for general classrooms in schools since education environment improvement project has been launched. This research suggests the best option for the heat pump heating and cooling system in educational buildings through economic assessments for four alternative systems based on electric heat pump (EHP) and gas engine driven heat pump (GHP), which are most widely used for elementary, middle and high schools. The model buildings are in the Y high school which has 24 classes of new construction building, which will be built soon. Annual energy consumption for alternative systems uses BECS 3.10, which can be used for system simulation.

• Korean Journal of Social Welfare
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• v.49
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• pp.296-318
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• 2002

The purpose of this study is to empirically analyze whether or not, if a community social service center was affiliated with a governing body running other community social service centers, the center would have better organizational performance in comparing to an independently running center. Data was collected from a nationwide mailed and self-administered survey, which 237 centers out of 343 community social service centers responded. Even if, the response rate was 72%, 218 centers were finally analyzed due to the weakness of reliability and incompleteness. By the way, measurement of organizational performance as the dependent variable has been substituted of the results of nationwide organizational evaluation project as the secondary data. One of findings is that 68% of 218 responding centers appeared to be affiliated with a governing body which running more than three other centers, while 41% being affiliated with a body which running more than five other centers. However, a logistic regression analysis which using organizational performance as the dependent variable, has failed to verify the hypothesis that a center which affiliated with a governing body running other centers has better organizational performance when comparing to an independent center. The researcher assumes that a part of governing bodies has better performance and improves competitiveness while the other larger part of them pursues simple organizational growth. Thus, this situation made that the overall evaluation of being affiliated with a large governing body was not positive.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.47.1-47.1
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• 2016

The determination of three dimensional parameters (e.g., radial speed, angular width, source location) of Coronal Mass Ejections (CMEs) is very important for space weather forecast. To estimate these parameters, several cone models based on a flat cone or a shallow ice-cream cone with spherical front have been suggested. In this study, we investigate which cone model is proper for halo CME morphology using 26 CMEs which are identified as halo CMEs by one spacecraft (SOHO or STEREO-A or B) and as limb CMEs by the other ones. From geometrical parameters of these CMEs such as their front curvature, we find that near full ice-cream cone CMEs are dominant over shallow ice-cream cone CMEs. Thus we develop a new full ice-cream cone model by assuming that a full ice-cream cone consists of many flat cones with different heights and angular widths. This model is carried out by the following steps: (1) construct a cone for given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, (4) minimize the difference between the estimated projection speeds with the observed ones. We apply this model to 12 SOHO halo CMEs and compare the results with those from other stereoscopic methods (a geometrical triangulation method and a Graduated Cylindrical Shell model) based on multi-spacecraft data.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.53.1-53.1
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• 2016

With the official start of the operations of the three 1.6 m KMTNet telescope systems from 2015 October, we have initiated a program named KMTNet Supernova Program (KSP) from 2015 to 2019 aiming at searching for supernovae (SNe), other optical transients and related sources. Taking advantage of the 24-hour coverage, high cadence and multi-color monitoring observations, this is optimal for discovering early SNe and peculiar ones. From the start of the previous test observing runs of ~half a year, we have performed observations on several nearby galaxy groups and nearby galaxies with short separations on the sky. We have developed data reduction/variable object search pipelines, meanwhile we have discovered some interesting transient objects. We also stacked all the images for given fields, searched for new objects/galaxies, and discovered several new dwarf galaxies, e.g., in the NGC 2784 galaxy group field (H. S. Park et al.'s talk). We will report the current project status and the results obtained.

• Journal of the Korean Geotechnical Society
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• v.28 no.6
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• pp.39-52
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• 2012

Magnetic sensing system and automated monitoring system based on digital hall sensor for ground settlement are developed to change traditional method for monitoring surface settlement and underground settlement by manual type and to overcome technical limits of existing automated settlement monitoring system. It's possible to monitor surface settlement and underground settlement with multi-points at the same time in a single hole with NX size. It was possible to verify technical confidence and stability by several case studies of soft ground improvement project.

• KIEAE Journal
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• v.10 no.6
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• pp.115-121
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• 2010

This paper is an outgrowth of many years of practicing real interior work projects and one of my responses to the question not only about the actual dimension of interior work surface but also about the classification of contemporary finishing materials in basic interior project of high-rise apartment houses. For this purpose, 8 conventional apartment units which are already-built or designed have been surveyed and the results are interpreted in the form of proportion of space and finishes. The data can be applied to make up a schematic design in the selection of environment-friendly interior works and assessment of the degree of sustainability. For further study, the basic data provided here can be used as an index to differentiate the occupants' desire toward green interior design for their own apartment spaces, comparing to the conventional interior work in the Korean market. Not surprisingly, wall paper is dominated to make the interior surface in apartment houses. In the percentile of the utilization of finishing materials, wood-flooring and coating materials like wet paint also ranked at the upper position.

• Journal of Ship and Ocean Technology
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• v.12 no.4
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• pp.1-6
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• 2008

Nowadays, the computational capability and graphical power based on PCs increase very rapidly every year. As a result, the complicated engineering or scientific problems that could have only been handled by supercomputers a couple of decades ago can now be routinely run on PCs. Besides, the PCs can be assembled in parallel to increase its computational capability theoretically without limitation. The Web-based interface and communication tools are also being enhanced very rapidly and the real-time distance learning (E-Learning) and project cooperation on web get increasing attention. Using the-state-of-the-art computational method, a number of complicated and computationally intensive problems are being solved by PCs. The results can be well demonstrated on screen by graphics and animation tools. Those examples include the simulations of fully nonlinear waves, their interactions with floating bodies, global-motion analysis of multi-unit floating production system including complicated mooring lines and risers. Several examples will be presented in this regard. Also, Web and java-applet based educational tools have been developed at Texas A&M University for better understanding of waves and wave-body interactions. The background and examples of such Web-based educational tools published in Kim et al. (2003) are briefly introduced here.