• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.12
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• pp.149-158
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• 2005

This paper proposes a congestion avoidance algorithm which provides stable throughput and transmission rate regardless of buffer size by limiting the TCP congestion window in fixed bandwidth networks. Additive Increase, Multiplicative Decrease (AIMD) is the most commonly used congestion control algorithm. But, the AIMD-based TCP congestion control method causes unnecessary packet losses and retransmissions from the congestion window increment for available bandwidth verification when used in fixed bandwidth networks. In addition, the saw tooth variation of TCP throughput is inappropriate to be adopted for the applications that require low bandwidth variation. We present an algorithm in which congestion window can be limited under appropriate circumstances to avoid congestion losses while still addressing fairness issues. The maximum congestion window is determined from delay information to avoid queueing at the bottleneck node, hence stabilizes the throughput and the transmission rate of the connection without buffer and window control process. Simulations have performed to verify compatibility, steady state throughput, steady state packet loss count, and the variance of congestion window. The proposed algorithm can be easily adopted to the sender and is easy to deploy avoiding changes in network routers and user programs. The proposed algorithm can be applied to enhance the performance of the high-speed access network which is one of the fixed bandwidth networks.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.5
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• pp.49-54
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• 2011

Case-based reasoning is an efficient method to find solutions for new problems by using past cases after appropriate changes. It is widely used in everyday life because it resembles the way human acts. In this paper, we propose a military system that generates the most appropriate tactics for CGF (Computer Generated Forces) by utilizing past practices. It indeed applies case-based reasoning at the process of armed conflict. When the CGF squad on a mission, they will be given an action plan to reach the final goal. In the process of executing, tactics for specific action should be organized such as attacks, ambushes, and tactical moves. By using the proposed method, tactics were generated by case-based reasoning. The proposed system successfully receives input through each command and control agent, measures the degree of similarity with the case in case DB, selects the most similar case, modifies, uses, and then stores it for next time.

• Management & Information Systems Review
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• v.36 no.5
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• pp.175-193
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• 2017

This study examines the effect of social capital formed on B to B inter - firm transactions on firm's performance through a research model developed around the mediating effect of knowledge absorption capacity. In other words, we examined how each level of social capital affects firm performance. by examining the dimensions of social capital that are not presented in previous studies, we have identified how each element of social capital affects corporate performance. in addition, the effects of knowledge absorption on firm performance are analyzed and presented in various ways. The results of the study are summarized as follows. First, social capital is divided into three dimensions. In other words, the relationship between structural elements, relational dimensions, and cognitive dimensions was verified. First, the structural dimension influenced the relational dimension, and the relational dimension had a positive effect on the cognitive dimension. this is meaningful in that it solved what is pointed out as a limit in previous studies. this is meaningful in that it verified what was pointed out as a limit in previous studies. secondly, the structural dimension influenced the cognitive dimension. Second, each component of social capital has a positive impact on knowledge absorption capacity. Finally, it was found that knowledge absorption capacity had a positive effect on the corporate culture, and it was confirmed that knowledge absorption capacity was important. the extent to which social capital is absorbed in BtoB transactions means that the performance of the two companies can be quite different.

• Phonetics and Speech Sciences
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• v.12 no.2
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• pp.63-72
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• 2020

This study aims to develop a video-based smart utterance deep analyser (SUDA) application that analyzes semiautomatically the utterances that child and mother produce during interactions over time. SUDA runs on the platform of Android, iPhones, and tablet PCs, and allows video recording and uploading to server. In this device, user modes are divided into three modes: expert mode, general mode and manager mode. In the expert mode which is useful for speech and language evaluation, the subject's utterances are analyzed semi-automatically by measuring speech and language factors such as disfluency, morpheme, syllable, word, articulation rate and response time, etc. In the general mode, the outcome of utterance analysis is provided in a graph form, and the manger mode is accessed only to the administrator controlling the entire system, such as utterance analysis and video deletion. SUDA helps to reduce clinicians' and researchers' work burden by saving time for utterance analysis. It also helps parents to receive detailed information about speech and language development of their child easily. Further, this device will contribute to building a big longitudinal data enough to explore predictors of stuttering recovery and persistence.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.4
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• pp.449-454
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• 2010

Lately, airborne digital camera and airborne laser scanner in field of airborne surveying are used to build geography information such as digital ortho photo map and DEM(Digital Elevation Model). In this study, 3D position accuracy is compared medium format CCD camera RCD105 with airborne digital camera DMC. For this, test area was decided for aerial photograph. And using 1/1,000 scale digital map, ground control points were selected for aerial triangulation and check points were selected for horizontal/vertical accuracy analysis using softcopy stereoplotter. Accuracy of RCD105 and DMC was estimated by result of aerial triangulation and result of check points measurement of using softcopy stereoplotter. In result of aerial triangulation, RMSE(Root Mean Square Error) X, Y, Z of RCD105 is 2.1, 2.2, 1.3 times larger than DMC. In result of check point measurement using softcopy stereoplotter, horizontal/ vertical RMSE of RCD105 is 2.5, 4.3 times larger than DMC. Even though accuracy of RCD105 is lower than DMC, it is maybe possible to make digital map and ortho photo using RCD105.

• Korean Journal of Construction Engineering and Management
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• v.8 no.4
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• pp.110-118
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• 2007

For deciding the owner's budget of the building construction in the predesign stage, the probabilistic methodologies for estimating the cost are often studied, however these parameter-based conceptual estimating methodology has limitation of applying it to the practical business because it hardly can link the design decision-making and the cost estimating and control. Besides if the result of detail estimating after detail design is over the budget, locally and arbitrarily control the level of interior design and fix the design. This research proposed the prototype-based cost estimating model for building interior construction which leads to estimate the interior cost easily linking with design decision-making and supports to evaluate the design alternatives in the schematic design and the design development stage for office buildings. The model divides the building on the design process by Element Breakdown Structure and presents the design alternative by selecting the elements of each room from the database accumulated the historical office buildings' prototypes and estimates the cost. The 2 case studies presented to validate the effectiveness of as the linking tool integrating the design and construction data and applicability to the practical design on the presented prototype-based model.

• Archives of design research
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• v.18 no.3 s.61
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• pp.55-62
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• 2005

Recently, the opening of the world economy and regional ization of national demand endless endeavors and investments to upbring design-industry for regional economic development. Our domestic commodities, declined in price competitiveness against China and Southeast Asian nations, need construction of brand image of commodities and consumers' response through expanded concernments in marketing spheres. The design-industry is a important means to strengthen competitiveness of the domestic industry through discrimination of commodities and creativity of high added value. Design-industry has some problems in circumstances; commodity development and marketing are below the level in the sphere of manufacture industry yet and businessmen are unwilling to invest demanded for development of new design. Establishment of the personal foundation, useful for accumulating competent designers' experiences and technologies, can not pass limit. In addition, a system and a policy to protect design-industry have a problem in effectiveness. Concrete strategies to activate design industry which meets social and cultural circumstances of Daegu and Gyeongbuk region are to establish policy for construction of specialists' infra, systematization of study & development of design, common ownership of information on design, and expansion of design company. The business to upbring design in the region should be operated to develop competitive commodities which is helpful to the regional economy and to increase value of the regional enterprises' brand. In addition, foundation of design should be expanded personal, material, and informational infra through design-centered so that they are helpful to activate economy of Daegu and Gyeongbuk through making design reformational cluster.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.2
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• pp.68-78
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• 2020

Crop models have been used to predict vegetable crop yield, which would have a considerable economic impact on consumers as well as producers. A small number of models have been developed to estimate growth and yield of vegetables due to limited availability of growth observation data in high-quality. In this study, we aimed to analyze the protocols designed for collection of the observation data for major vegetable crops including cabbage, radish, garlic, onion and pepper. We also designed the protocols suitable for development and verification of a vegetable crop growth model. In particular, different measures were proposed to improve the existing protocol used by Statistics Korea (KOSTAT) and Rural Development Administration (RDA), which would enhance reliability of parameter estimation for the crop model. It would be advantageous to select sampling sites in areas where reliable weather observation data can be obtained because crop models quantify the response of crop growth to given weather conditions. It is recommended to choose multiple sampling sites where climate conditions would differ. It is crucial to collect time series data for comparison between observed and simulated crop growth and yield. A crop model can be developed to predict actual yield rather than attainable yield using data for crop damage caused by diseases and pests as well as weather anomalies. A bigdata platform where the observation data are to be shared would facilitate the development of crop models for vegetable crops.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1047-1055
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• 2006

We patterned nano-width lines on a super hard bulk diamond substrate by varying the ion beam current and ion beam sources with a dual beam field ion beam (FIB). In addition, we successfully fabricated two-dimensional nano patterns and three-dimensional nano plate modules. We prepared nano lines on a diamond and a silicon substrate at the beam condition of 30 kV, 10 pA $\sim$ 5 nA with $Ga^+$ ion and $H_2O$ assisted ion sources. We measured each of the line-width, line-depth, etched line profiles, etch rate, and aspect ratio, and then compared them. We confirmed that nano patterning was possible on both a bulk diamond and a silicon substrate. The etch rate of $H_2O$ source can be enhanced about two times than that of Ga source. The width of patterns on a diamond was smaller than that on a silicon substrate at the same ion beam power The sub-100 nm patterns on a diamond were made under the charge neutralization mode to prevent charge accumulation. We successfully made a two-dimensional, 240 nm-width text of the 300-lettered Lord's Prayer on a gem diamond with 30 kV-30 pA FIB. The patterned text image was readable with a scanning electron microscope. Moreover, three dimensional nano-thick plate module fabrication was made successfully with an FIB and a platinum deposition, and electron energy loss spectrum (EELS) analysis was easily performed with the prepared nano plate module.

• Korean Security Journal
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• no.42
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• pp.309-334
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• 2015

Now it is a proper time to discuss on the issue of crisis negotiation more in-depth. Thus far, studies on crisis negotiations have been mere manual style guidelines of "what to do". More substantial and rigorous theoretical propositions and empirical studies await for the future development of crisis negotiation field. This article contributes to the theoretical enrichment of the study of crisis negotiation field. Conventionally, two problems of misperceptions are raised in crisis negotiation. For instance, even though two parties used the same word, there can appear a substantial difference. Even worse, in many cases parties of negotiation send misinformation intentionally or unintentionally. This noise of communication can cause a serious misperception for parties of crisis negotiation including police officers, perpetrators, and hostages. However, this issue has not yet discussed in the field of crisis negotiation in Korea. This paper pointed out such important but not yet focused issue. It first discusses about the problem of perception and misperception. Next, it presents the negative impacts of such perception and misperception in crisis negotiation communication. Finally, it suggests the policy implications.