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Establishment Method of the Regulatory Framework for Communications Reflecting the Ecosystem Elements (생태계 요소를 반영한 방송통신 규제체계의 정립 방안)

  • Hong, Dae-Sik;Choe, Dong-Uk
    • Journal of Legislation Research
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    • no.41
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    • pp.401-434
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    • 2011
  • The discussion on the adoption of the horizontal regulatory framework is underway to overcome the problems regarding the vertical regulatory framework resulting from a convergence of broadcasting and telecommunications services. Recently, however, the horizontal regulatory framework shows its limitation to regulate the ecosystem established mainly by Google and Apple. The existing horizontal regulatory framework does not fully reflect the characteristics of the two-sided market and the change in the competition structure in the broadcasting and telecommunications sector. What is important to note is that if the existing horizontal regulatory framework is simply applied to the ecosystem, a regulatory imbalance can be caused among ecosystems. The existing horizontal regulatory framework, which is subject to a value chain structure, categorizes business entities into either contents layer or transmission layer and applies the same regulation to all business entities in the same category. However, in the ecosystem, a keystone-player can be categorized into different layers depending on its strategy. Therefore, if the existing horizontal regulatory framework is applied as it is, the regulatory imbalance between keystone-players located in less regulated areas and keystone-players located in more regulated areas occurs resulting in a distortion of competition. There are two possible ways to establish a new regulatory framework to prevent the distortion of competition likely to be caused by the adoption of a horizontal regulatory system. First, a new ecosystem regulatory framework different from the existing one can be established. Second, the horizontal regulatory framework can be modified to reflect the ecosystem elements. The first approach is hard to adopt given the current situation as the approach requires the analysis of all broadcasting and telecommunications ecosystems including mobile and wired services; currently research and study on the competition conditions in the ecosystems is not enough. Therefore, this paper supports the second approach proposing a modified horizontal regulatory framework through the improvement of institutions and remedies suitable for accommodating the ecosystem elements. This paper intends to propose a way to regulate broadcasting and telecommunications ecosystems taking into consideration the ecosystem elements on top of the Telecommunications Business Act, Broadcasting Act, IPTV Act, the competition condition evaluation system of the Basic Act on Broadcasting and Telecommunications Development, and regulation on common carriers under the Telecommunications Business Act.

A Proposal for Korean armed forces preparing toward Future war: Examine the U.S. 'Mosaic Warfare' Concept (미래전을 대비한 한국군 발전방향 제언: 미국의 모자이크전 수행개념 고찰을 통하여)

  • Chang, Jin O;Jung, Jae-young
    • Maritime Security
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    • v.1 no.1
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    • pp.215-240
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    • 2020
  • In 2017, the U.S. DARPA coined 'mosaic warfare' as a new way of warfighting. According to the Timothy Grayson, director of DARPA's Strategic Technologies Office, mosaic warfare is a "system of system" approach to warfghting designed around compatible "tiles" of capabilities, rather than uniquely shaped "puzzle pieces" that must be fitted into a specific slot in a battle plan in order for it to work. Prior to cover mosaic warfare theory and recent development, it deals analyze its background and several premises for better understanding. The U.S. DoD officials might acknowledge the current its forces vulnerability to the China's A2/AD assets. Furthermore, the U.S. seeks to complete military superiority even in other nation's territorial domains including sea and air. Given its rapid combat restoration capability and less manpower casualty, the U.S. would be able to ready to endure war of attrition that requires massive resources. The core concept of mosaic warfare is a "decision centric warfare". To embody this idea, it create adaptability for U.S. forces and complexity or uncertainty for the enemy through the rapid composition and recomposition of a more disag g reg ated U.S. military force using human command and machine control. This allows providing more options to friendly forces and collapse adversary's OODA loop eventually. Adaptable kill web, composable force packages, A.I., and context-centric C3 architecture are crucial elements to implement and carry out mosaic warfare. Recently, CSBA showed an compelling assessment of mosaic warfare simulation. In this wargame, there was a significant differences between traditional and mosaic teams. Mosaic team was able to mount more simultaneous actions, creating additional complexity to adversaries and overwhelming their decision-making with less friendly force's human casualty. It increase the speed of the U.S. force's decision-making, enabling commanders to better employ tempo. Consequently, this article finds out and suggests implications for Korea armed forces. First of all, it needs to examine and develop 'mosaic warfare' in terms of our security circumstance. In response to future warfare, reviewing overall force structure and architecture is required which is able to compose force element regardless domain. In regards to insufficient defense resources and budget, "choice" and "concentration" are also essential. It needs to have eyes on the neighboring countries' development of future war concept carefully.

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A Study on Developing a VKOSPI Forecasting Model via GARCH Class Models for Intelligent Volatility Trading Systems (지능형 변동성트레이딩시스템개발을 위한 GARCH 모형을 통한 VKOSPI 예측모형 개발에 관한 연구)

  • Kim, Sun-Woong
    • Journal of Intelligence and Information Systems
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    • v.16 no.2
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    • pp.19-32
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    • 2010
  • Volatility plays a central role in both academic and practical applications, especially in pricing financial derivative products and trading volatility strategies. This study presents a novel mechanism based on generalized autoregressive conditional heteroskedasticity (GARCH) models that is able to enhance the performance of intelligent volatility trading systems by predicting Korean stock market volatility more accurately. In particular, we embedded the concept of the volatility asymmetry documented widely in the literature into our model. The newly developed Korean stock market volatility index of KOSPI 200, VKOSPI, is used as a volatility proxy. It is the price of a linear portfolio of the KOSPI 200 index options and measures the effect of the expectations of dealers and option traders on stock market volatility for 30 calendar days. The KOSPI 200 index options market started in 1997 and has become the most actively traded market in the world. Its trading volume is more than 10 million contracts a day and records the highest of all the stock index option markets. Therefore, analyzing the VKOSPI has great importance in understanding volatility inherent in option prices and can afford some trading ideas for futures and option dealers. Use of the VKOSPI as volatility proxy avoids statistical estimation problems associated with other measures of volatility since the VKOSPI is model-free expected volatility of market participants calculated directly from the transacted option prices. This study estimates the symmetric and asymmetric GARCH models for the KOSPI 200 index from January 2003 to December 2006 by the maximum likelihood procedure. Asymmetric GARCH models include GJR-GARCH model of Glosten, Jagannathan and Runke, exponential GARCH model of Nelson and power autoregressive conditional heteroskedasticity (ARCH) of Ding, Granger and Engle. Symmetric GARCH model indicates basic GARCH (1, 1). Tomorrow's forecasted value and change direction of stock market volatility are obtained by recursive GARCH specifications from January 2007 to December 2009 and are compared with the VKOSPI. Empirical results indicate that negative unanticipated returns increase volatility more than positive return shocks of equal magnitude decrease volatility, indicating the existence of volatility asymmetry in the Korean stock market. The point value and change direction of tomorrow VKOSPI are estimated and forecasted by GARCH models. Volatility trading system is developed using the forecasted change direction of the VKOSPI, that is, if tomorrow VKOSPI is expected to rise, a long straddle or strangle position is established. A short straddle or strangle position is taken if VKOSPI is expected to fall tomorrow. Total profit is calculated as the cumulative sum of the VKOSPI percentage change. If forecasted direction is correct, the absolute value of the VKOSPI percentage changes is added to trading profit. It is subtracted from the trading profit if forecasted direction is not correct. For the in-sample period, the power ARCH model best fits in a statistical metric, Mean Squared Prediction Error (MSPE), and the exponential GARCH model shows the highest Mean Correct Prediction (MCP). The power ARCH model best fits also for the out-of-sample period and provides the highest probability for the VKOSPI change direction tomorrow. Generally, the power ARCH model shows the best fit for the VKOSPI. All the GARCH models provide trading profits for volatility trading system and the exponential GARCH model shows the best performance, annual profit of 197.56%, during the in-sample period. The GARCH models present trading profits during the out-of-sample period except for the exponential GARCH model. During the out-of-sample period, the power ARCH model shows the largest annual trading profit of 38%. The volatility clustering and asymmetry found in this research are the reflection of volatility non-linearity. This further suggests that combining the asymmetric GARCH models and artificial neural networks can significantly enhance the performance of the suggested volatility trading system, since artificial neural networks have been shown to effectively model nonlinear relationships.

The Smartphone User's Dilemma among Personalization, Privacy, and Advertisement Fatigue: An Empirical Examination of Personalized Smartphone Advertisement (스마트폰 이용자의 모바일 광고 수용의사에 영향을 주는 요인: 개인화된 서비스, 개인정보보호, 광고 피로도 사이에서의 딜레마)

  • You, Soeun;Kim, Taeha;Cha, Hoon S.
    • Information Systems Review
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    • v.17 no.2
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    • pp.77-100
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    • 2015
  • This study examined the factors that influence the smartphone user's decision to accept the personalized mobile advertisement. As a theoretical basis, we applied the privacy calculus model (PCM) that illustrates how consumers are engaged in a dynamic adjustment process in which privacy risks are weighted against benefits of information disclosure. In particular, we investigated how smartphone users make a risk-benefit assessment under which personalized service as benefit-side factor and information privacy risks as a risk-side factor accompanying their acceptance of advertisements. Further, we extend the current PCM by considering advertisement fatigue as a new factor that may influence the user's acceptance. The research model with five (5) hypotheses was tested using data gathered from 215 respondents through a quasi-experimental survey method. During the survey, each participant was asked to navigate the website where the experimental simulation of a mobile advertisement service was provided. The results showed that three (3) out of five (5) hypotheses were supported. First, we found that the intention to accept advertisements is positively and significantly influenced by the perceived value of personalization. Second, perceived advertisement fatigue was also found to be a strong predictor of the intention to accept advertisements. However, we did not find any evidence of direct influence of privacy risks. Finally, we found that the significant moderating effect between the perceived value of personalization and advertisement fatigue. This suggests that the firms should provide effective tailored advertisement that can increase the perceived value of personalization to mitigate the negative impacts of advertisement fatigue.

Variation in Heading States of Korean Winter Wheat under Winter Temperature Rise of Toluca in Mexico (멕시코 톨루카 지역의 겨울 기온상승에 따른 한국 밀 품종의 출수생태 변이)

  • Park, TaeIl;Chung, Uran
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.3
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    • pp.99-108
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    • 2016
  • The shuttle breeding of Korean winter wheat has been able to develop high-yielding and day-length-intensive varieties with a wide range of ecologic adoption. However, the phenology of winter wheat has been changed due to recent rises in the winter temperature of Toluca and increasing frequency of high temperatures. We defined two wheat groups (group II and III) with vernalization and evaluated the impact of cold exposure duration and heading ratio due to changes in sowing dates by measuring changes in cold exposure duration and corresponding heading states of each group. The wheat cultivars were sown on three dates in two years. The cold exposure requirement of wheat sown on 6 November 2013 was unfulfilled. The cold exposure requirement of wheat sown on 22 November and 6 December 2013 was fulfilled. However, in 2014, the cold exposure requirement of wheat sown on 5 and 20 November was fulfilled, but that of wheat sown on 5 December was unfulfilled. The differences for the two early November sowings were because winter temperature rises, which caused high temperatures in 2013, whereas early November 2014 saw normal temperatures for the area. The heading ratio of group II did not show a clear difference among the three sowing dates, while the heading ratio of group III was reduced by about half. This implies that the efficiency of shuttle breeding of group III will be high since it showed strong sensitivity to changes in sowing dates. We calculated future sowing dates of each group under near future climate scenarios; the future available sowing dates of group II were projected, but the dates of group III were never estimated in the temperature rise scenario in Toluca. Our findings suggest that change of sowing dates should be considered in the strategy for shuttle breeding of Korean winter wheat.

Development of a Real-Time Mobile GIS using the HBR-Tree (HBR-Tree를 이용한 실시간 모바일 GIS의 개발)

  • Lee, Ki-Yamg;Yun, Jae-Kwan;Han, Ki-Joon
    • Journal of Korea Spatial Information System Society
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    • v.6 no.1 s.11
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    • pp.73-85
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    • 2004
  • Recently, as the growth of the wireless Internet, PDA and HPC, the focus of research and development related with GIS(Geographic Information System) has been changed to the Real-Time Mobile GIS to service LBS. To offer LBS efficiently, there must be the Real-Time GIS platform that can deal with dynamic status of moving objects and a location index which can deal with the characteristics of location data. Location data can use the same data type(e.g., point) of GIS, but the management of location data is very different. Therefore, in this paper, we studied the Real-Time Mobile GIS using the HBR-tree to manage mass of location data efficiently. The Real-Time Mobile GIS which is developed in this paper consists of the HBR-tree and the Real-Time GIS Platform HBR-tree. we proposed in this paper, is a combined index type of the R-tree and the spatial hash Although location data are updated frequently, update operations are done within the same hash table in the HBR-tree, so it costs less than other tree-based indexes Since the HBR-tree uses the same search mechanism of the R-tree, it is possible to search location data quickly. The Real-Time GIS platform consists of a Real-Time GIS engine that is extended from a main memory database system. a middleware which can transfer spatial, aspatial data to clients and receive location data from clients, and a mobile client which operates on the mobile devices. Especially, this paper described the performance evaluation conducted with practical tests if the HBR-tree and the Real-Time GIS engine respectively.

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Protein Engineering of Flavin-containing Monooxygenase from Corynebacterium glutamicum for Improved Production of Indigo and Indirubin (인디고와 인디루빈의 생산을 증대하기 위한 플라빈-함유 모노옥시게나제의 단백질공학)

  • Jung, Hye Sook;Jung, Hae Bin;Kim, Hee Sook;Kim, Chang Gyeom;Lee, Jin Ho
    • Journal of Life Science
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    • v.28 no.6
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    • pp.656-662
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    • 2018
  • Flavin-containing monooxygenases from Corynebacterium (cFMOs) were mutagenized based on homology modeling to develop variants with an enhanced indigoid production capability. The four mutants, F170Y, A210G, A210S, and T326S, which fused to a maltose-binding protein (MBP), were constructed, and their biochemical properties were characterized. Of these, purified MBP-T326S required a higher concentration of exogenous FAD (100 mM) than the wild-type MBP-cFMO for optimal activity and showed a 3.8-fold increase in the $k_{cat}/K_m$ value at $100{\mu}M$ FAD compared to that of MBP-cFMO at $2{\mu}M$ FAD. The indole oxygenase activities of MBP-T326S decreased to 63-77% compared to that of the MBP-cFMO In addition, MBP-T326S displayed a very low level of futile NADPH oxidase activities (21-24%) in the absence of a substrate. Mutant proteins except for T326S displayed similar $K_m$ and increased $k_{cat}/K_m$ values compared to the wild-type. MBP-F170Y and -A210S mutants showed elevated indole oxygenase activity higher than 3.1- and 2.9-fold, respectively, in comparison with MBP-cFMO. When indigoid production was carried out in LB broth with 2.5 g/l of tryptophan, Escherichia coli expressing cFMO produced 684 mg/l of indigo and 104 mg/l of indirubin, while cells harboring T326S produced 1,040 mg/l of indigo and 112 mg/l of indirubin. The results indicate that the production of indigo was 13% higher when compared to a previous report in which an E. coli expressing FMO from Methylophaga produced 920 mg/l of indigo. The protein engineering of cFMO based on homology modeling provided a more rational strategy for developing indigoid-producing strains.

The Relationships among Mathematics Achievement, Spatial Ability, and Verbal Achievement for Engineering Freshmen and Gender Differences (공과대학 신입생들의 공간 시각화 능력, 수학 성취도와 언어 성취도 사이의 관계 및 성별 차이에 관한 연구)

  • Kim, Yon Mi
    • Communications of Mathematical Education
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    • v.29 no.3
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    • pp.553-571
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    • 2015
  • Mathematical, verbal, and spatial abilities are known as three important indicators for the success in the STEM disciplines. In this study, Purdue Spatial Visualization Test-Rotation, College Entrance Scholastic Aptitude Test- Math and Verbal score of engineering freshmen students have been used to find the relationships among these areas. In addition, gender differences in spatial visualization, verbal achievement and mathematical achievement have been investigated, too. In this research, I found that gender difference was highest in spatial visualization ability, followed by verbal achievement and smallest in mathematical achievement. Substantial number of male students possess high level of spatial abilities, but only half of female students were at the same level where their male colleagues were. The correlation between spatial ability and mathematical ability was negligible, contrary to former researches on elementary and middle school students. But the correlation was stronger for female students than male students. The correlation between mathematical achievement and verbal achievement was negative. It reflects the fact that when one section of SAT score is low, score of other sections should be higher to get admitted to college. Gender difference in mathematics was smallest for high achieving spatial ability group. For low spatial ability group gender difference in mathematics achievement has been observed, too. To find the combined contribution of spatial and verbal abilities to mathematics achievement, students were divided into 4 ability groups. Mathematics achievement decreased in the order of (1) high spatial -low verbal group, (2) low spatial - low verbal group, (3) high spatial - high verbal group, (4) low spatial - high verbal group.

Development of Market Growth Pattern Map Based on Growth Model and Self-organizing Map Algorithm: Focusing on ICT products (자기조직화 지도를 활용한 성장모형 기반의 시장 성장패턴 지도 구축: ICT제품을 중심으로)

  • Park, Do-Hyung;Chung, Jaekwon;Chung, Yeo Jin;Lee, Dongwon
    • Journal of Intelligence and Information Systems
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    • v.20 no.4
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    • pp.1-23
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    • 2014
  • Market forecasting aims to estimate the sales volume of a product or service that is sold to consumers for a specific selling period. From the perspective of the enterprise, accurate market forecasting assists in determining the timing of new product introduction, product design, and establishing production plans and marketing strategies that enable a more efficient decision-making process. Moreover, accurate market forecasting enables governments to efficiently establish a national budget organization. This study aims to generate a market growth curve for ICT (information and communication technology) goods using past time series data; categorize products showing similar growth patterns; understand markets in the industry; and forecast the future outlook of such products. This study suggests the useful and meaningful process (or methodology) to identify the market growth pattern with quantitative growth model and data mining algorithm. The study employs the following methodology. At the first stage, past time series data are collected based on the target products or services of categorized industry. The data, such as the volume of sales and domestic consumption for a specific product or service, are collected from the relevant government ministry, the National Statistical Office, and other relevant government organizations. For collected data that may not be analyzed due to the lack of past data and the alteration of code names, data pre-processing work should be performed. At the second stage of this process, an optimal model for market forecasting should be selected. This model can be varied on the basis of the characteristics of each categorized industry. As this study is focused on the ICT industry, which has more frequent new technology appearances resulting in changes of the market structure, Logistic model, Gompertz model, and Bass model are selected. A hybrid model that combines different models can also be considered. The hybrid model considered for use in this study analyzes the size of the market potential through the Logistic and Gompertz models, and then the figures are used for the Bass model. The third stage of this process is to evaluate which model most accurately explains the data. In order to do this, the parameter should be estimated on the basis of the collected past time series data to generate the models' predictive value and calculate the root-mean squared error (RMSE). The model that shows the lowest average RMSE value for every product type is considered as the best model. At the fourth stage of this process, based on the estimated parameter value generated by the best model, a market growth pattern map is constructed with self-organizing map algorithm. A self-organizing map is learning with market pattern parameters for all products or services as input data, and the products or services are organized into an $N{\times}N$ map. The number of clusters increase from 2 to M, depending on the characteristics of the nodes on the map. The clusters are divided into zones, and the clusters with the ability to provide the most meaningful explanation are selected. Based on the final selection of clusters, the boundaries between the nodes are selected and, ultimately, the market growth pattern map is completed. The last step is to determine the final characteristics of the clusters as well as the market growth curve. The average of the market growth pattern parameters in the clusters is taken to be a representative figure. Using this figure, a growth curve is drawn for each cluster, and their characteristics are analyzed. Also, taking into consideration the product types in each cluster, their characteristics can be qualitatively generated. We expect that the process and system that this paper suggests can be used as a tool for forecasting demand in the ICT and other industries.

A Study on Hybrid Characteristics of Public Space in Contemporary Cities Reinterpreted by the Idea of Liminal Space (역공간(Liminal Space) 개념으로 해석한 현대도시 공공공간의 혼성적 특성에 관한 연구)

  • Zoh, Kyung-Jin;Han, So-Young
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.4
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    • pp.49-59
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    • 2011
  • This study is a reinterpretation of characteristics of public space in contemporary cities with a view to liminal space. The conditions of pubic space now cannot be captured through the existing discourses of publicness, and public space. The basic premise of the study is that the idea of liminal space or liminality is useful to grasp the fluid and hybrid attribute of public space in contemporary cities. Liminal space, originally from anthropological studies, is the intermingled stage between two realms and the sustained period of the ritual. The idea has been widely used for various cultural phenomenon and spatial experiences. A literature review on public space and liminal space was carried out. Cases pertaining to public space with a view to liminal space were examined and discussed in detail. Through the careful reading of several public spaces with an angle toward liminal space, the new perspective toward public space will be drawn out. First, we need to emphasize the fluid spectrum of public space rather than the serial stage such as the public, the semi-public, the semi-private, and the private. Second, the idea will contribute to understanding the flexible state depending upon time. What we can learn from case studies is the volatile characteristics in public space as a common phenomenon support its vitality. This interpretation will contribute to the perception of a new horizon of public space. The nature of public space is unpredictable and free. In reality, the spectrum of public space will expand and fluctuate. Ironically, public space can be vitalized through enhancing and activating the private space. The intimate and complicated interface between the two realms is a key issue. The boundary of public space might be redefined to embrace the flexible the fragile nature of changing public space. These research implications will guide the thoughtful design and management of pubic space.