• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1313-1317
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• 2006

In this study, various hydraulic phenomena were analyzed from the dam model experiments and the analyzed results were compared with existing computation results. Sungduk dam model structures were constructed using Froude similarity law by 1:50 scale. From the measurements of hydraulic phenomena at spillway channel, an improvement method was trying to be suggested over shortcoming of existing design plan. The result of model experiment showed no big difference with that of each part's numerical interpretation. Sidewall overflows were observed, as water conveyance occurred due to the linear characteristics of spillways, which raised the necessity for improving the linear forms of spillways. Also, it was judged to be necessary improving load pressure and establishing protective structures at the riverbed grounds of downstream channels.

• Structural Engineering and Mechanics
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• v.29 no.6
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• pp.623-642
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• 2008

While spatial plastic mechanism analysis has been widely and successfully applied to thinwalled steel structures to analyse the post-failure behaviour of sections and connections, there remains some contention in the literature as to the basic capacity of an inclined yield line. The simple inclined hinge commonly forms as part of the more complex spatial mechanism, which may involve a number of hinges perpendicular or inclined to the direction of thrust. In this paper some of the existing theories are compared with single inclined yield lines that form in flange outstands, by comparing the theories with plate tests of plates simply supported on three sides with the remaining (longitudinal) edge free. The existing mechanism theories do not account for different in-plane displacement gradients of the loaded edge, nor the slenderness of the plates, and produce conservative results. A modified theory is presented whereby uniform and non-uniform in-plane displacements of the loaded edge of the flange, and the slenderness of the flange, are accounted for. The modified theory is shown to compare well with the plate test data, and its application to flanges that are components of sections in compression and/or bending is presented.

• Asian Journal for Public Opinion Research
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• v.1 no.2
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• pp.103-127
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• 2014

This study reviews existing research on the measurement of and the relationship between political diversity and political participation. It addresses the inconsistency in the arguments of existing studies researching the influence of political diversity on political participation. It attempts to find the cause in the variety of approaches to conceptualize and operationalize the two variables. As the measure of political diversity, political network heterogeneity and network attributes are discussed in detail in specific relation to political participation. As for political participation, an in-depth analysis of various ways to understand different forms of political involvement is presented. Implications for public opinion research are discussed.

• Textile Coloration and Finishing
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• v.25 no.2
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• pp.140-151
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• 2013

In order to investigate the mechanical properties of working clothes materials considering industrial settings, the test weaving materials were compared with the existing materials depending on the season. The material design of the test fabrics were changed through fineness, composition, density of materials then subsequently treated with functional finish. As a result of evaluation of the forms according to KES-FB system, Koshi was deduced, and Numeri and Fukurami were increased. Thereby, the test weaving materials became flexible, surface became smoother, elasticity and volume characteristics indicated to have been improved. Consequently, the THV value of working clothes materials for test weaving was increased compared to existing materials which indicated improved result of the total hand value. Specially, the winter cloth material indicated improved drape characteristics and dimensional characteristics, showed improved liveliness as being compressed softly.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.3 no.3
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• pp.251-265
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• 2009

VoIP service is the transmission of voice data using SIP protocol on an IP-based network. The SIP protocol has many advantages, such as providing IP-based voice communication and multimedia service with low communication cost. Therefore, the SIP protocol disseminated quickly. However, SIP protocol exposes new forms of vulnerabilities to malicious attacks, such as message flooding attack. It also incurs threats from many existing vulnerabilities as occurs for IP-based protocol. In this paper, we propose a new virtual proxy to cooperate with the existing Proxy Server to provide state monitoring and detect SIP message flooding attack with IP/MAC authentication. Based on a proposed virtual proxy, the proposed system enhances SIP attack detection performance with minimal latency of SIP packet transmission.

• ETRI Journal
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• v.33 no.6
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• pp.831-840
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• 2011

This paper focuses on codebook-based precoding for space-division multiple access/orthogonal frequency-division multiple access (SDMA-OFDMA) systems aiming to guarantee high throughput for their users as well as to mitigate interference to fixed satellite service (FSS). A systematic design of SDMA codebook for subband-based OFDMA is proposed, which forms multiple orthogonal beams with common spatial null in the direction of a victim FSS earth station (ES). The design enables both transmitter and receiver to independently construct identical codebook by sharing only on the direction angle of an FSS ES, which takes fewer overhead bits than Gram-Schmidt process, a general method satisfying our design criterion. A system-level throughput evaluation shows that the proposed precoding provides superior performance over existing spectrum sharing method, that is, subband deactivation. The spectrum sharing analysis shows that the proposed precoding, even with an estimation error of the direction angles of an FSS ES, causes lower interference than existing precoding, knockdown precoding.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.8 no.1
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• pp.52-60
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• 1996

Existing equations of bed load transport are reviewed mainly considering the meaning and. role of variables used in the equations. The development of several equations and the problems of each equation are investigated by comparing their computed results against field or laboratory data. On the basis of the review remedies of each equation are suggested, and modified forms of existing equations are developed for wider application and improvement in the accuracy. Empirical parameters introduced in each equation are determined by testing them against Brownlie(1985)'s collected data, and discrepancy ranges of the refined equations are shown to see their degrees of accuracy.

• Korean Institute of Interior Design Journal
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• no.32
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• pp.28-35
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• 2002

After 18th century in Korea, a tendency of the traditional folk houses shows not only the typical types but also the cultural areas in terms of each regional part. The existing folk houses are selected in order to compare the characteristic of the plans with those of the central region in Korea. Moreover this region has been a collided zone of culture and military from the old period of the Three Kingdoms, because the district of Che-chun is located between the southern part and the central one. So its culture and housing plan showed as unique forms, so-called the Culture of Frontier and Composite. Consequently the purposes of this study are to grasp the characteristic of those plans and to compare the plan types with ones of the central region. For the attainment of the above goal, this investigated study is prosecuted by means of the existing 6-folk houses in Che-chun city.

• Journal of architectural history
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• v.18 no.6
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• pp.85-101
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• 2009

The Purpose of this paper is a study on the characteristics of Campidoglio hill plan by Michelangelo. 1. The plan of the Campidoglio hill is composed of the harmonized and united space, in spite of the existing conditions of a steep flight of land, a irregular site shape, a building of each other different dimension and form. And it is newly changed by site left through the modification of existing building elevation, utilization of existing building for new planning, connection with existing building and newly planned building from plaza composition of trapezoid form. 2. The concept of planning of the Campidoglio hill is planned by compromising for requirements of Baroque after Renaissance which urban planning characteristics of Baroque is as the relation with urban street through a inclined stairs and process such as street-approach stairs-plaza-symbol of inside plaza-building. 3. The section plan of the Campidoglio hill is planned by which can be easily approached to the plaza through the inclined stairs of gentle angle from street at the center east-west direction of main axis such as main axis, utilizing the existing site shape, and it is composed of the convex shape ascending gently at the center central part of the plaza. 4. The plan of the Campidoglio hill is composed of the elation with the axis of existing Senatorio palace, building planning of perfect balance, plaza composition of reversed trapezoid form bybuilding planning, central concentrated planning of buildings surrounding plaza. 5. The three palace of the plan of the Campidoglio hill is composed of the concept as theater which the stage background forms the front elevation of Senatorio palace higher two palace and the wings of either side of stage form the front elevation of Conservatori palace and Nuovo palace, surrounding three palace elevation around plaza of trapezoid form.

• International Journal of Contents
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• v.14 no.1
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• pp.39-44
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• 2018

Today, cars have developed into intelligent automobiles that combine advanced control equipment and IT technology to provide driving assistance and convenience to users. These vehicles provide infotainment services to the driver, but this does not improve the safety of the driver. Accordingly, V2X communication, which forms a network between a vehicle and a vehicle, between a vehicle and an infrastructure, or between a vehicle and a human, is drawing attention. Therefore, various techniques for improving channel estimation performance without changing the IEEE 802.11p standard have been proposed, but they do not satisfy the packet error rate (PER) performance required by the C-ITS service. In this paper, we analyze existing channel estimation techniques and propose a new channel estimation scheme that achieves better performance than existing techniques. It does this by applying the updated matrix for the data pilot symbol to the construct data pilot (CDP) channel estimation scheme and by further performing the interpolation process in the frequency domain. Finally, through simulations based on the IEEE 802.11p standard, we confirmed the performance of the existing channel estimation schemes and the proposed channel estimation scheme by coded PER.