• Land and Housing Review
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• v.13 no.4
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• pp.45-53
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• 2022

This paper investigates empirically the lead-lag relation between the 'apartment price index' and 'Internet search volume'. This study uses Naver Trend Index as a proxy for Internet search volume. An increase in Internet search volume on the apartment price index indicates an increase in people's attention to an apartment. Different from previous studies exploring the relation between 'the released price index of the apartment' and 'Naver Trend Index', this study investigates the relation of the Naver Trend Index with 'the fundamental price component of an apartment' and 'the transitory price component of an apartment', respectively. The results of the Granger causality test reveal that there are bidirectional Granger causalities between the 'released price' and Naver Trend Index. In addition, the 'fundamental price component of an apartment' and Naver Trend Index have a feedback relation, while 'the transitory price component of an apartment' Granger causes the Naver Trend Index uni-directionally. The impulse response function analysis indicates that the shock of apartment prices increases Naver Trend Index in the first month. Overall, The close relationship between apartment prices and Naver Trend Index suggests that increases in the movement of apartment prices are positively associated with public attention on the apartment market.

• IEIE Transactions on Smart Processing and Computing
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• v.3 no.4
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• pp.195-204
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• 2014

This paper presents the depth evaluation for object detection by automated assembling robots. Pattern distortion analysis from a structured light system identifies an object with the greatest depth from its background. An automated assembling robot should prior select and pick an object with the greatest depth to reduce the physical harm during the picking action of the robot arm. Object detection is then combined with a depth evaluation to provide contour, showing the edges of an object with the greatest depth. The contour provides shape information to an automated assembling robot, which equips the laser based proxy sensor, for picking up and placing an object in the intended place. The depth evaluation process using structured light for an automated electronics assembling robot is accelerated for an image frame to be used for computation using the simplest experimental set, which consists of a single camera and projector. The experiments for the depth evaluation process required 31 ms to 32 ms, which were optimized for the robot vision system that equips a 30-frames-per-second camera.

• Journal of the Korea Society for Simulation
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• v.11 no.2
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• pp.1-16
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• 2002

The need for network security is being increasing due to the development of information communication and internet technology. In this paper, firewall models, operating system models and other network component models are constructed. Each model is defined by basic or compound model, referencing DEVS formalism. These models and the simulation environment are implemented with MODSIM III, a general purpose, modular, block-structured high-level programming language which provides direct support for object-oriented programming and discrete-event simulation. In this simulation environment with representative attacks, the following three attacks are generated, SYN flooding and Smurf attack as an attack type of denial of service, Mail bomb attack as an attack type of e-mail. The simulation is performed with the models that exploited various security policies against these attacks. The results of this study show that the modeling method of packet filtering system, proxy system, unix and windows NT operating system. In addition, the results of the simulation show that the analysis of security performance according to various security policies, and the analysis of correlation between availability and confidentiality according to security empowerment.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.4
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• pp.106-113
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• 2011

Human resource theories of becoming entrepreneurs or self-employed rather than finding employment are compared as applied to fit the occupational data of technological entrepreneurs and technology jobs. The human capital theory posits that technological entrepreneurs are prepared to become a jack-of-all-trades with a variety of fields of education. Hobo theory of entrepreneurship assumes that entrepreneurs have strong taste against concentrating on a few activities, which tend to drive entrepreneurs away from employed jobs depressing their expected income. Another theory assumes that entrepreneurs have some unobserved productive qualities and abilities over employed people. Immigrant entrepreneurs could presumably be pressured out of employment under racial discrimination. Since technology jobs are mostly filled by those educated in the science and technology fields, and they presumably offer great reward to professional concentration, technological entrepreneurs may not benefit from becoming jacks-of-all-trades compared to finding employment in technological jobs income-wise. Asian immigrants in the 2000 US Census data are compared to white immigrants in technological jobs to test alternative human resource theories of entrepreneurship. Using English language ability as a proxy for the variety of education, I find in the white immigrant technological entrepreneurs support for the jack-of-all-trades theory, while in the Asian immigrant technological entrepreneurs hobo theory is supported. In the Asian technological workers only there appears the significant self-selection or comparative advantage component, while at the same time discriminatory components are significant.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.4
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• pp.73-82
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• 2013

The main objective of this study was to evaluate Representative Concentration Pathways (RCP) scenarios-based flood risk at a Si-Gun level. A bias correction using a quantile mapping method with the Generalized Extreme Value (GEV) distribution was performed to correct future precipitation data provided by the Korea Meteorological Administration (KMA). A series of proxy variables including CN80 (Number of days over 80 mm) and CX3h (Maximum precipitation during 3-hr) etc. were used to carry out flood risk assessment. Indicators were normalized by a Z-score method and weighted by factors estimated by principal component analysis (PCA). Flood risk evaluation was conducted for the four different time periods, i.e. 1990s, 2025s, 2055s, and 2085s, which correspond to 1976~2005, 2011~2040, 2041~2070, and 2071~2100. The average flood risk indices based on RCP4.5 scenario were 0.08, 0.16, 0.22, and 0.13 for the corresponding periods in the order of time, which increased steadily up to 2055s period and decreased. The average indices based on RCP8.5 scenario were 0.08, 0.23, 0.11, and 0.21, which decreased in the 2055s period and then increased again. Considering the average index during entire period of the future, RCP8.5 scenario resulted in greater risk than RCP4.5 scenario.

• The Journal of Industrial Distribution & Business
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• v.12 no.8
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• pp.41-52
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• 2021

Purpose: The study aims to analyze effects of wage on FDI inflows based on the threshold of institutional quality in 14 developing economies of Southeast and South Asia over the period from 2000-2017. Research design, data, and methodology: The study applies a fixed effect panel threshold regression. As a proxy for the institutional quality, it uses the six components of Worldwide Governance Indicators or a compound index obtained by an average of the six components. The data were taken from World Bank, the Chinn & Ito Database, and UNCTAD. To the best of our knowledge, no researches so far have considered the threshold of institutional quality in estimating the effect of wage on FDI inflows. Results: The composite index and each component of the six indicators of institutional quality except for voice and accountability, and regulatory quality are found to have nonlinear effects on FDI inflows. When the institutional quality is below the threshold, wage affects FDI inflows negatively. When the institutional quality is above the threshold, however, wage does not significantly affect FDI inflows. Conclusions: The effect of wage on FDI inflows varies depending on whether the institutional quality of the target countries is above or below the threshold.

• The Journal of Industrial Distribution & Business
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• v.12 no.10
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• pp.31-41
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• 2021

Purpose: This study estimates the threshold values of institutional quality through investigating the non-linear effect of six sub-indices of Worldwide Governance Indicators on FDI inflows in 34 developing countries in Asia and Eastern Europe over the period from 2000-2017. Research Design, data and methodology: GMM EGLS is employed which does not include the lagged value of the dependent variable as an independent variable. As a proxy for the institutional quality, either one of the six sub-indices of WGI from World Bank or the composite index obtained through a principal component analysis is used in a separate model. Results: An improvement in institutional quality, when the quality stays below a certain threshold level, does not increase FDI inflows, and only when the quality is above the threshold, it can positively influence FDI inflows. The threshold values of political stability and absence of violence, government effectiveness, and rule of law are relatively higher than those of the other dimensions of WGI. Conclusion: Institutional quality of the developing economies of Asia and Eastern Europe has a non-linear effect on FDI inflows. The target countries need to upgrade their institutional quality above the threshold in order to attract more FDIs.

• Journal of Advanced Navigation Technology
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• v.14 no.4
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• pp.537-544
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• 2010

The PMIPv6 is a network controlled mobility management protocol in which mobile nodes never participate in IP mobility protocol signaling. One issue in using PMIPv6 for multicast service is that a new component should be added as the mobility management functions are located not on the device but on the network. Currently, standardization activities for providing muticast services with PMIPv6 have been actively in progress. This paper addresses some issues about the on-going standardization works for providing efficient real-time multicast services with PMIPv6, and proposes a scheme for minimizing hand over delays and packet losses by using a new neighbor cell reporting method. The proposed scheme has been verified to outperform the existing scheme in hand over delay and packet loss perfonnrmces by using computer simulations.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.11a
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• pp.37-43
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• 2004

The response of the CCCma coupled climate model to the imposition of LGM conditions is investigated. The global mean SAT and SST decrease by about $10^{\circ}C$ and $5.6^{\circ}C$ in the coupled model. Tropical SST decreases by $6.5^{\circ}C$, whereas CLIMAP reconstructions suggest that the tropics cool by only about $1.7^{\circ}C$, although the larger tropical cooling is consistent with the more recent proxy estimates. With the incorporation of a full ocean component, the coupled model gives a realistic spatial SST pattern, capturing features associated with ocean dynamics that are seen in the CLIMAP reconstructions. The larger decrease of the surface temperature in the model is associated with a reduction in global precipitation rate (about 15%). The tropical Pacific warm pool retreats to the west and a mean La $Ni\tilde{n}a$-like response is simulated with less precipitation over the central Pacific and more in the western tropical Pacific. The more arid ocean climate in the LGM results in an increase in SSS almost everywhere. This is particularly the case in the Arctic Ocean where large SSS increase is due to a decrease in river discharge to the Arctic Ocean associated with the accumulation of snow over the ice sheet, but in the North Atlantic by contrast SSS decreases markedly. This remarkable reduction of SSS in the North Atlantic is attributed to an increase in fresh water supply by an increase in discharges from the Mississippi and Amazon rivers and an increase in P-E over the North Atlantic ocean itself. The discharges increase in association with the wetter LGM climate south of the Laurentide ice sheet and in South America. The fresh water capping of the northern North Atlantic results in a marked reduction of deep convection and consequently a marked weakening of the North Atlantic overturning circulation. In the LGM, the maximum overturning stream function associated with the NADW formation decreases by about 60% relative to the control run, while in the Southern Ocean, oceanic convection is stronger in the LGM due to reduced stratification associated with an increase in SSS and a decrease in SST and the overturning stream function associated with the formation of AABW and the outflow increases substantially.

• The KIPS Transactions:PartD
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• v.9D no.6
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• pp.1145-1156
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• 2002

We propose a web document transcoding technique that translates existing web pages designed for desktop computers into an appropriate form for hand-held devices connected to the wireless internet. By defining a content block based on a visual separation and using it as a minimum unit for analyzing and converting processes, we can get web pages converted more exactly. We also apply the reallocation of the content block and the generation of new index in order to provide convenient interface without left-right scrolling in small screen devices. These methods, compared with existing ways such as text level summary or partial extraction method, can provide efficient navigation and a full recognition of web documents. To gain those transcoding benefits, we propose the Layout-Forming Tag Analysis Algorithm that analyzes structural tags, which motivate visual separation and the Component Grouping Algorithm that extracts the content block. We also classify and rearrange the content block and generate the new index to produce an appropriate form of web pages for small display devices. We have designed and implemented our transcoding system in a proxy server and evaluated the methods and the algorithms through an analysis of transcoded results. Our transcoding system showed a good result on most of popular web pages that have complicated structures.