• Journal of Korea Society of Industrial Information Systems
• /
• v.19 no.2
• /
• pp.85-91
• /
• 2014

The objective of the research is to automatically recognize railway objects from MLS data in which 9 key objects including terrain, track, bed, vegetation, platform, barrier, posts, attachments, powerlines are targeted. The proposed method can be divided into two main sub-steps. First, multi-scale contextual features are extracted to take the advantage of characterizing objects of interest from different geometric levels such as point, line, volumetric and vertical profile. Second, by considering contextual interactions amongst object labels, a contextual classifier is utilized to make a prediction with local coherence. In here, the Conditional Random Field (CRF) is used to incorporate the object context. By maximizing the object label agreement in the local neighborhood, CRF model could compensate the local inconsistency prediction resulting from other local classifiers. The performance of proposed method was evaluated based on the analysis of commission and omission error and shows promising results for the practical use.

• Journal of Periodontal and Implant Science
• /
• v.39 no.2
• /
• pp.129-138
• /
• 2009

Purpose: This study was designed to compare the bond regeneratiom effects of treatment using silk fibroin membrane ( Nanogide-S$^{(R)}$ ) resorbable barrier with control group treated by polyactic acid / polylacticglycolic acid membrane(Biomesh$^{(R)}$ ) Methods: 44 severe bone loss on extraction socket from 44 patients were used in this study. In experimental group 22 sites of them were treated by silk fibrin membrane as and the other 22 sites were treated by polyactic acid/ polylacticglycolic acid membrane as a control group. Clinical parameters including recovered bone width, length and radiographic parameter of vertical length were evlauated at base line and 3 months after surgery. Results: 1) Severe bone width, length was significantlly decreased in two group. 2) Bone width, length was significantlly decreased in two group. 3) Decreased bone width, length and radiographic examination differences between group. Conclusions: On the basis of these results, silk fibrin resorbable membrane has similar bone regeneration ability to polyactic acid / polylacticglycolic acid membrane in guided bone regeneration for severe bone loss defect on extraction socket.

• Journal of the Microelectronics and Packaging Society
• /
• v.13 no.4
• /
• pp.45-50
• /
• 2006

Copper via filling is the important factor in 3-D stacking interconnection of SiP (system in package). As the packaging density is getting higher, the size of via is getting smaller. When DC electroplating is applied, a defect-free hole cannot be obtained in a small size via hole. To prevent the defects in holes, pulse and pulse reverse current was applied in copper via filling. The holes, $20\and\;50{\mu}m$ in diameter and $100{\sim}190\;{\mu}m$ in height. The holes were prepared by DRIE method. Ta was sputtered for copper diffusion barrier followed by copper seed layer IMP sputtering. Via specimen were filled by DC, pulse and pulse-reverse current electroplating methods. The effects of additives and current types on copper deposits were investigated. Vertical and horizontal cross section of via were observed by SEM to find the defects in via. When pulse-reverse electroplating method was used, defect free via were successfully obtained.

• Korean Journal of Materials Research
• /
• v.23 no.10
• /
• pp.550-554
• /
• 2013

As continued scaling becomes increasingly difficult, 3D integration has emerged as a viable solution to achieve higher bandwidths and good power efficiency. 3D integration can be defined as a technology involving the stacking of multiple processed wafers containing integrated circuits on top of each other with vertical interconnects between the wafers. This type of 3D structure can improve performance levels, enable the integration of devices with incompatible process flows, and reduce form factors. Through silicon vias (TSVs), which directly connect stacked structures die-to-die, are an enabling technology for future 3D integrated systems. TSVs filled with copper using an electro-plating method are investigated in this study. DC and pulses are used as a current source for the electro-plating process as a means of via filling. A TiN barrier and Ru seed layers are deposited by plasma-enhanced atomic layer deposition (PEALD) with thicknesses of 10 and 30 nm, respectively. All samples electroplated by the DC current showed defects, even with additives. However, the samples electroplated by the pulse current showed defect-free super-filled via structures. The optimized condition for defect-free bottom-up super-filling was established by adjusting the additive concentrations in the basic plating solution of copper sulfate. The optimized concentrations of JGB and SPS were found to be 10 and 20 ppm, respectively.

• Korean Chemical Engineering Research
• /
• v.51 no.4
• /
• pp.527-530
• /
• 2013

I present the behavior of colloidal adsorption to an oil-water interface in the presence of electrolyte in an aqueous subphase. The optical laser tweezers and the piezo controller are used to trap an individual polystyrene microsphere in water and forcibly transfer it to the interface in the vertical direction. Addition of an electrolyte (i.e., NaCl) in the aqueous subphase enables the particle to attach to the interface, whereas the particle escapes from the trap without the adsorption in the absence of the electrolyte. Based on the analytical calculations of the optical trapping force and the electrostatic disjoining pressure between the particle and the oil-water interface, it is found that a critical energy barrier between them should exist. This study will provide a fundamental understanding for applications of colloidal particles as solid surfactants that can stabilize the immiscible fluid-fluid interfaces, such as emulsions (i.e., Pickering emulsions) and foams.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.20 no.1
• /
• pp.25-33
• /
• 2008

Water waves are generated mainly by winds in open seas and large lakes. They carry a significant amount of energy from winds into near-shore region. Thereby they significantly contribute to the regional hydrodynamics and transport process, producing strong physical, geological and environmental impact on coastal environment and on human activities in the coastal area. Furthermore an accurate prediction of the hydrodynamic effects due to wave interaction with offshore structures is a necessary requirement in the design, protection and operation of such structures. In the present paper surface and internal waves scattering by thin surface-piercing and bottom-standing vertical barriers in a two-layer fluid is analyzed in two-dimensions within the context of linearized theory of water waves. The reflection coefficients for surface and internal waves are computed and analyzed in various cases. It is found that wave reflection is strongly dependent on the interface location and the fluid density ratio apart from the barrier geometry.

• Journal of Korea Trade
• /
• v.24 no.6
• /
• pp.115-134
• /
• 2020

Purpose - International trade leads to the international division of labor, improving the efficiency of the global economic system. Transport costs are a more serious barrier to international trade than customs tariffs. An increase in competition in the transport sector may thus lead to a reduction in transport costs. However, if a carrier's nationality significantly influences transport costs, simply adding more competing carriers of different nationalities would be ineffective. Therefore, it is necessary to establish national or regional carriers to influence competition and reduce transport costs. This study investigates this "nationality effect" by treating Hanjin Shipping's collapse as a natural experiment. Design/methodology - The theoretical basis of this study is the 3rd-degree price discrimination in container shipping market. By using the monthly data of container freight rates of Korea, China and Japan, this study shows the so-called Korea Premiums, which are the empirical counterparts of nationality effect in Korea container shipping market. For this empirical investigation, the structural model with state-space form is used and the dummy models are also estimated. In addition, because China has been also affected by the Hanjin's collapse, the China premiums are considered too. Findings - Compared with Japan's case, it is shown that there had been the so-called Korea premiums since the collapse of Hanjin Shipping. These results are robust from both the state-space model and dummy models. The time pattern of Korea premiums was consistent with the market evolution, especially the pattern of substitutability in container shipping markets. In addition, this paper shows the magnitude of Korea premiums. Originality/value - The argument of this study that the nationality effect can be interpreted as an extended concept of the home market effect is original, which is expected to evoke future research efforts. Further, the discussion on the shipping industrial policy from both horizontal and vertical aspects will provide the relevant policy makers with solid information, especially for the policy coordination in a global scale.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.5
• /
• pp.591-596
• /
• 2023

This study developed a program that can produce videos easily and conveniently, focusing on teenage media producers. Through user research, we identified the needs and problems of teenage producers, and implemented a character customization function desired by users and an emotion and action recommendation system using GPT. In the rendering process, the final image was created by combining audio and video using OpenCV and FFmpeg. Teenage users who do not have expertise in video production can customize web drama characters through a simple interface and receive recommendations for emotions and actions with the help of GPT. The program of this study is expected to be a tool that can help teenage users who do not have expertise in editing and directing to produce high-quality videos, lower the entry barrier to video production, and contribute to the development of the one-person media industry. do. In the future, we plan to provide a video production environment considering mobile or vertical resolution versions.

• KDI Journal of Economic Policy
• /
• v.13 no.1
• /
• pp.3-33
• /
• 1991

Since the early 1980's, the Korean government has gradually been widening the Korean market to foreign consumer goods. This, combined with the increased purchasing power of the Korean consumers resulting from the continued economic growth of the country, has sparked a spectacular influx of foreign consumer goods into Korea, ranging from BMW's to chopsticks. Import of foreign consumer goods amounted to more than 6 billion dollars in 1989 and is continuing to grow at a rapid rate. The increased import of foreign consumer goods doubtlessly improved the overall welfare of the Korean consumers by providing them with a wider range of options to choose from, by lowering the prices of some of the consumer goods domestically produced, and also by forcing the producers of some Korean goods to face competition with better foreign goods, thus giving them an incentive to raise the quality of their products. However, it is agreed by most economists that this increase in general welfare has been much smaller than what they had expected at the outset. Consumer prices of most imported consumer goods are easily double the import price, and in some cases, more than treble the import prices. Further, there has not been a noticeable drop in the prices of domestically produced consumer goods. Much of the blame has been attributed to the distribution sector of Korea. The objective of this paper is to analyze the imported consumer goods distribution sector of Korea, focusing on the possible sources of the poor performance of that sector, and to make policy suggestions that could potentially increase the welfare. This paper differs from all the previous research by others on this subject in that it analyzes the imported consumer goods distribution sector of Korea as a vertical structure. The distribution sector of an imported consumer good is a vertical structure since it consists of an international market, an import stage, and domestic wholesale and retail markets, in that order vertically. Our study naturally includes the analysis of the vertical restraints as well as the analysis of the industrial organization of each horizontal stage in the vertical structure. Each horizontal component of the imported consumer goods distribution sector is basically a monopolistically competitive market differentiated by characteristics of goods and by the locations and the services of firms. Further, restrictive dealership and resale price maintenance are found to be widely in use. Our main findings are the follwing; First, most consumer goods are imported monopolistically or oligopolistically through restrictive dealership contracts between foreign producers and domestic importers. Such restrictive dealership gives importers market power in the domestic market and explains many of the large discrepancies betwen the consumer prices and the import prices of many goods. Korean anti - trust law does not cover the issues arising from the market power of an importer resulting from a restrictive dealership contract. Second, some major producers of Korean goods are also importers of foreign goods that are substitutes of their products. The import of substitutes by major domestic producers is anti - competitive because it tends to raise the prices of both domestic goods and foreign goods, and also because it reduces the incentive of the domestic producers to raise the quality of their products. Third, wholesalers and retailers widely use resale price maintenance as a price fixing mechanism, and while this is against the anti- trust law, it seldom gets noticed. Fourth, the high level of rents of real estate for commercial use works as an entry barrier to the distribution sector and results in reduced competition by the firms in that sector. Finally, there are information problems. Consumers have inferior information to firms about the quality of a foreign consumer good that they have not tried before. Such information asymmetry often enables firms to raise prices. In addition, information asymmetry between importers frequently delays the import of cheaper substitutes. In order to alleviate the problems indentified above, we suggest the following policy changes. The government should strengthen the anti - trust law and its enforcement to regulate restrictive import contracts, import of competing goods by major domestic producers, and RPM by wholesalers and retailers that is aimed at price fixing. In addition, the government should loosen its tight real estate policy to encourage investment in the distribution sector. Finally, we suggest that the import price revelation policy that has been in use for some items since 1990 be expanded to most imported consumer goods that are introduced for the first time to give consumer better information and be used only for the period of time needed to inform sufficient number of consumers.

• Journal of Soil and Groundwater Environment
• /
• v.16 no.4
• /
• pp.1-9
• /
• 2011

Bentonite has been generally used as vertical cutoff barrier material and reported to have several problems regarding its low workability, drying shrinkage cracking by particle cohesion, and ineffective waterproof ability under sea water condition. In this study, the particle sealant, the furnace slag coated by the mixture of bentonite, sepiolite and guargum, was developed to compensate these weak points and the hydraulic conductivity of the particle sealant was evaluated. Drying shrinkage cracking and swelling index was estimated to find the optimal mixing ratio of bentonite, sepiolite and guargum. The hydraulic conductivity of the particle sealants having different amount of sealant (bentonite-sepioliteguargum mixture) coating the furnace slag was estimated using the rigid wall permeameter and flexible wall permeameter. The results showed that drying shrinkage cracking was not found in the bentonite-sepiolite mixture with 20% sepiolite contents and the results from free swelling tests for the sealant having 1 : 0.025, 1 : 0.05 and 1 : 0.075 of weight ratios of bentonite-sepiolite mixture and guargum under simulated sea water condition were higher than those for the bentonitesepiolite mixture without guargum under tap water condition. These three sealants were coated on the furnace slag with 50% and 60% of sealant in the particle sealant and the hydraulic conductivity was estimated. In the cases of the particle sealants having 20% sepiolite in the bentonite-sepiolite mixture and 1 : 0.075 weight ratio of the bentonite-sepiolite mixture and guargum, the hydraulic conductivity from the rigid wall permeameter was below $1.0{\times}10^{-7}$ cm/sec under simulated sea water condition. The hydraulic conductivity of the particle sealant having $1.0{\times}10^{-6}$~$1.0{\times}10^{-7}$ cm/sec by the rigid wall permeameter was estimated using the flexible wall permeameter and found to be below $1.0{\times}10^{-7}$ cm/sec.