• Spatial Information Research
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• v.9 no.2
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• pp.239-261
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• 2001

A large suite of official statistical data sets has been compiled for geographical units under the national directives, and it is the quantitative regional analysis procedures that could add values to them. This paper reports our attempts at prototyping a statistical GIS which is capable of serving over the Web a variety of regional analysis routines as well as value-added statistics and maps. A pilot database of some major statistical data was ingested for the city of Seoul. The baseline subset of regional analysis methods of practical usage was selected and accommodated into the business logic of the target system, which ranges from descriptive statistics, regional structure/inequality measures, spatial ANOVA, spatial (auto) correlation to regression and residual analysis. The leading-edge information technologies including the application server were adopted in the system design and implementation so that the database, analysis modules and analytic mapping components may cooperate seamlessly behind the Web front-end. The prototyped system supports tables, maps, and files of downloadable format for input and output of the analyses. One of the most salient features of out proposed system is that both the database and analysis modules are extensible via the bi-directional interface for end users; The system provides users with operators and parsers for algebraic formulae such that the stored statistical variables may be transformed and combined into the newly-derived set of variables. This functionality eventually leads to on-the-fly fabrication of user-defined regional analysis algorithms. The stored dataset may also be temporarily augmented by user-uploaded dataset; The extension of this form, in essence, results in a virtual database which awaits for users commands as usual. An initial evaluation of the proposed system confirms that the issues involving the usage and dissemination of information can be addressed with success.

• Spatial Information Research
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• v.9 no.2
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• pp.291-307
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• 2001

In today's environmental engineering practice, many technologies such as GIS have been adopted to analyze chemical and biological process in water bodies and pollutants movements on the land surface. However, the linkage between spatially represented land surface pollutants and the in-stream processes has been relatively weak. This lack of continuity needs to develop a method in order to link the spatially-based pollutant source characterization with the water quality modeling. The objective of this thesis was to develop a two-way(forward and backward) link between ArcView GIS software and the USEPA water quality model, WASP5. This thesis includes a literature review, the determination of the point source and non-point source loadings from WASP5 modeling, and the linkage of a GIS with WASP5 model. The GIS and model linkage includes pre-processing of the input data within a GIS to provide necessary information for running a model in the forms of external input files. The model results has been post-processed and stored in the GIS database to be reviewed in a user defined form such as a chart, or a table. The interface developed from this study would provide efficient environment to support the easier decision making form water quality management.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.739-748
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• 2013

In this study, analytical works for the induced winds due to traveling vehicles on highway have been conducted by Computation Fluid Dynamics (CFD). The traveling condition was considered in two cases: (a) single direction and (b) bi-direction. The analysis was focused on the effects of the induced winds on the upper part of a median strip while the aerodynamic characteristics of the vehicles were directly analyzed in the previous studies. From the analysis results, it has been found that the maximum magnitude of the induced winds was 2.2 m/s when the vehicles travel with the speed of 50 km/h. Additionally, 4.0 m/s and 5.3 m/s were obtained with the speed of 90 km/h and 120 km/h, respectively. Especially, the induced winds was generated about 84% of the vehicle speed at 1.0 m above from the median strip when the vehicles travel with the speed of 120 km/h. The induced winds was maintained during the very short period while the traveling. conclusively, it is noted that the wind power generation can be possible by using the small-sized wind power generators installed on median strips throughout the analytical results in this study.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.799-804
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• 2016

Broadband powerline communication (BPLC) uses distribution lines as a medium for achieving effective bidirectional data communication along with electric current flow. As the material characteristics of power lines are not good at the communication channel, the development of power line communication (PLC) systems for internet, voice, and data services requires measurement-based models of the transfer characteristics of the network suitable for performance analysis by simulation. In this paper, an analytic model describing a complex transfer function is presented to obtain the attenuation and path parameters for a multipath power line model. The calculated results demonstrated frequency-selective fading in multipath channels and signal attenuation with frequency, and were in good agreement with the experimental results. Inductive coupling units are used as couplers for coupling the signal to the power line to avoid physical connections to the distribution line. The inductance of the ferrite core, which depends on the frequency, determines the cut-off frequency of the inductive coupler. Coupling loss can be minimized by increasing the number of windings around the coupler. Coupling efficiency was improved by more than 6 dB with three windings compared to the results obtained with one winding.

• The Korean Journal of Zoology
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• v.39 no.1
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• pp.1-11
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• 1996

The SR 95531, a GABA antagonist was microinjected into either the pretectum nuclei (nucleus Superficialis Synencephali nSS) or the nBOR (nucleus Ectomammilaris nEM) of chickens. Monocular optokinetic nystagmus (01(N) was reorded by the search coil technique before and after unilateral intracerebral drug administration. Unilateral microinjections of SR 95531 into either the nSS or nEM induce a reversible increase of gain in OKN directed by contralateral eye for both directions of stimulation. The administration into the nSS increased directional asymmetry by increasing the T~ component velocity gain more strongly than the N-T component velocity gain. On the other hand, the unilateral administration of the drug into the nEM suppressed the diretional O1(N asymmetry by increasing the N-T component velocity gain more strongly than the T-N component velocity gain. The nSS seems especially involved in monocular OKN in response to a T-N stimulation, while the nEM seems more involved in the OKN response to N-T stimulation. These results indicate that the drug suppresses GABAergic inhibition at the mesencephalic level. The increase in gain of OKN directed by the ipsilateral eye to microinjeded nuclei could account for the strong interactions existing between these two mesencephalic structures responsible for horizontal OKN.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.331-337
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• 2020

The study analyzes the appropriate number of people per a household by applying an evacuation simulation to a 27-floor apartment in accordance with the NFPA 101 standard. The results of the analysis are as follows. First, if there are three people residing in each household, there would be 156 households in total, of which 85.25% were evacuated within 5 minutes. Second, 208 households with 4 residents were evacuated within 5 minutes. Third, if there are five people residing in each household, there would be a total of 260 households and 71.92% of residents were evacuated within 5 minutes. Lastly, 62.82% of the 312 households, each consisting of 6 people, were evacuated within 5 minutes. Measures to reduce evacuation time include determining the width of the stairs according to the number of people indoors, the number of floors in the building, the slope of stairs, and the users' characteristics, the design reflecting the ventilation conditions of the stairs, the installment of outdoor evacuation stairs, two-way stairs, evacuation lift, and the installation of an evacuation safety zone for people to evacuate outside of the building in the middle floors. In addition, measures, such as the mandatory installation of automatic emergency door open-close device to the rooftop, are required to facilitate rooftop evacuation.

• Journal of Digital Contents Society
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• v.9 no.3
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• pp.399-412
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• 2008

The 21st century has been changed into a knowledge-oriented society, which means our society is more dependent on information and moves toward information. The mixing of broadcasting and co mmunication prevails and it makes possible a new type of broadcasting service. Depending on that, a broadcasting is being changed into a consumer-oriented service to satisfy the demands of consum ers in a new media age. It makes us attain to the personal media age to be possible interactive com munication unlike existing one-way transmission. As a result, new complex media are commercialize d and the instance is DMB. DMB is said 'my own TV' or 'TV in my own hands'. But it has limit t o retransmit existing broadcast programs. So hereafter, DMB broadcasting must be produced with co ntents suited its properties out of retransmitting existing contents. It is necessary to analyze exactly properties and service fields of DMB media to make an establish production direction of contents for DMB. This paper intends to suggest overall optimized image-contents production direction including appropriate program developments, a proper running time, visual expressions such as a camera angle and walking etc... DMB contents suited with its properties will give more familiarities to DMB users. Besides, DMB is expected to be a new culture watching broadcasting.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.12
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• pp.127-134
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• 2005

Lost packet robustness is an most important quality measure for voice over IP networks(VoIP). Recovery of the lost packet from the received information is crucial to realize this robustness. So, this paper proposes the lost packet recovery method from the received information for real-time communication for CELP coder. The proposed BS-PLC (Both Side Packet Loss Concealment) based WSOLA(Waveform Shift OverLab Add) allow the lost packet to be recovered from both the 'previous' and 'next' good packet as the LP parameter and the excitation signal are respectively recovered. The burst of packet loss is modeled by Gilbert model. The proposed scheme is applied to G.729 most used in VoIP and is evaluated through the SNR(signal to noise) and the MOS(Mean Opinion Score) test. As a simulation result, The proposed scheme provide 0.3 higher in Mean Opinion Score and 2 dB higher in terms of SNR than an error concealment procedure in the decoder of G.729 at $20\%$ average packet loss rate.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.5
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• pp.511-521
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• 2015

The thermal bridge occurring in a building influences its thermal performance and durability. The domestic typical multi-unit residential buildings suffer thermal losses resulting from thermal bridges of the balcony slab. To minimize the thermal loss between inside and outside of the balcony slab, thermal bridge breaker(TBB) systems have been developed and applied in building construction. Although thermal bridge breaker systems for reinforced concrete(RC) wall-slab joints can improve the thermal performance of a building, it is necessary to verify the structural performance of TBB systems whether they provide proper resistance for cyclic loading. In order to investigate the structural characteristics of TBB systems embedded in RC slabs, cyclic tests of wall-slab joints were performed by applying two reversed cycles at each up to 30 cycles. The test results show that the RC slabs embedding TBBS systems can present excellent structural performance and the maximum moment capacity, energy dissipation capacity and ductility of TBBs systems are enhanced compared to those of the typical RC slabs.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.181-189
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• 2010

The placenta, which is a temporary organ derived from the fetus during pregnancy, is critical to support fetus development via optimal regulation between mother and fetus. Trophoblast as a major cell population of the placenta is one of the earliest to differentiate and shows an extensive proliferation or/and differentiation up to the formation of the placenta. The role of the trophoblast show dynamic changes from early embryo implantation to placentation during pregnancy. Implantation of the blastocyst into the endometrium of the maternal uterus is mediated by invasion of the differentiated trophoblast (e.g. syncytiotrophoblast) from the trophectoderm. During pregnancy, the unique role of the trophoblast is to invasion, eroding, and metastasizing in the placenta as well as to ensure appropriate bidirectional nutrient or waste flow required for growth and maturation of the embryo. The dysfunction of the trophoblast during pregnancy can result in several gynecological diseases including preeclampsia and congenital malformation in neonatal medicine. Therefore, trophoblasts act as a conclusive factor in placental and fetal development. This brief review outlines the classification of trophoblast and its function in the placenta during pregnancy. Also, we introduce the latest research in trophoblast for implantation and the placenta development, and the application potential of trophoblast for infertility and obstetrical diseases.