• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.5 s.311
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• pp.89-100
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• 2006

The carotid intima-media thickness (IMT) is very important, because the severity of it is an independent predictor of transient cerebral ischemia, stroke, and coronary events such as myocardial infarction. The conventional image processing to measure the IMT has not been satisfactory, because the methods have relied on the manual section drawing and a regional segmentation by differential estimation. We propose a new image processing technology effective to extract features from the carotid artery image whose pixels have the directional vector properties with composed color distribution. The technique we presented here is not by differential variation but by verification of the layer properties of carotid artery image. Iterated vertical and horizontal analysis and segmentation of the IMT image show the vector characteristics. This new technique makes it possible to cluster the layers statistically, and to classify mathematical correlation between regions and resulting in correct measurements of thickness and its variation. The advantages and effectiveness of this approach are applicable to region process and character extraction of such a vector image.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.7
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• pp.36-45
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• 1999

In order to control the flow of traffics in ATM networks and optimize the usage of network resources, an efficient control mechanism is necessary to cope with congestion and prevent the degradation of network performance caused by congestion. In this paper, Buffered Leaky Bucket which applies the same control scheme to a variety of traffics requiring the different QoS(Quality of Service) and Neural Networks lead to the effective buffer utilization and QoS enhancement in aspects of cell loss rate and mean transfer delay. And the cell scheduling algorithms such as DWRR and DWEDF for multiplexing the incoming traffics are enhanced to get the better fair delay. The network congestion information from cell scheduler is used to control the predicted traffic loss rate of Neural Leaky Bucket, and token generation rate and buffer threshold are changed by the predicted values. The prediction of traffic loss rate by neural networks can enhance efficiency in controlling the cell loss rate and cell transfer delay of next incoming cells and also be applied for other traffic controlling schemes. Computer simulation results performed for random cell generation and traffic prediction show that QoSs of the various kinds of traffcis are increased.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.4
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• pp.412-421
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• 2010

As a most conservative, minimally invasive trial against early caries lesions, resin infiltration concept has been introduced and studied mainly about effective materials and pre-treatment methods of surface layers to arrest the lesion effectively, which is still going on. This study was performed with an aim of evaluating the efficacy of arresting the caries process in the natural incipient lesions in spite of removing the surface layers and we obtained the results as follows: 1. It was revealed that infiltration groups(1, 3, 5) showed lower radio-density decline between pre- and posttreatment than control groups(2, 4, 6)(p<0.05). 2. Group 5, in which the surface layer was removed with hydrochloric acid, showed the most significant anticariogenic effect(p<0.05). 3. Under SEM evaluation after infiltration, group 1 and 3 showed more irregular destruction and intensive loss of surface layers than group 5. In conclusion, it was thought resin infiltration can be an effective tool against the early caries lesions although surface layers are removed.

• Membrane Journal
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• v.24 no.5
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• pp.367-374
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• 2014

In the present study, disc-type LSCF/GDC (20 : 80 vol%) dual-phase membranes having porous LSC/GDC (50 : 50 vol%) active layers were prepared and effect of active layers on oxygen ion transport behavior was investigated. Introduction of active layers improved drastically oxygen flux due to enhanced electron conductivity and oxygen surface exchange activity. As firing temperature of active layer increased from $900^{\circ}C$ to $1000^{\circ}C$, oxygen flux increased due to improved contact between membrane and active layer or between grains of active layer. The enhanced contact would improve oxygen ion and electron transports from active layer to membrane. Also, as thickness of active layer increased from 10 to $20{\mu}m$, oxygen flux decreased since thick active layer rather prevented oxygen molecules diffusing through the pores. And, STF infiltration improved oxygen flux due to enhanced oxygen reduction reaction rate. The experimental data announces that coating and property control of active layer is an effective method to improve oxygen flux of dual-phase oxygen transport membrane.

• Journal of Intelligence and Information Systems
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• v.10 no.2
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• pp.147-163
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• 2004

For the purchase of a cheaper product on the Internet, many customers have been trying to search online shopping mall sites and visit comparison-pricing shops that compare prices and other criteria of the product. Others have been participating into online auction markets or group-buying markets. However, a lot of online shopping malls, auction markets, and group-buying markets provide the same product with different prices. Since these marketplaces have different price settlement mechanism, it is very difficult for the customers to determine marketplace to purchase, considering different kinds of marketplaces at the same time. To overcome such limitations, decision rules and solution procedures for purchase decision making are necessary, which can cover multiple marketplaces simultaneously. For this purpose, purchase decision making in each market must be conducted to maximize customer's utility, and conflicts with other marketplaces must be resolved. Therefore, we have developed the rules and methods that can negotiate cooperatively the purchase decision making in several marketplaces, and designed an architecture of Intelligent Buyer Agent and a message structure to support the idea.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.2
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• pp.171-179
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• 2008

RBAC(Role based Access Control) is effective way of managing user's access to information object in enterprise level and e-government system. The concept of RBAC is that the access right to object in a system is not directly assigned o users but assigned by being a member of a role which is defined in a organization. RBAC is utilized for controling access range of privacy but it does not support the personal legal right of control over information and right of limited access to the self. Nor it contains the way of observation of privacy flow that is guided in a legal level. In this paper, extended RBAC model for protecting privacy will be suggested and discussed. Two components of Data Right and Assigning Data Right are added to existed RBAC and the definition of each component is redefined in aspect of privacy preservation. Data Right in extended RBAC represents the access right to privacy data. This component provides the way of control over who can access which privacy and ensures limitation of access quantity of privacy. Based on this extended RBAC, implemented examples are presented and the evaluation is discussed by comparing existed RBAC with extended RBAC.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.367-384
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• 2014

This study addresses an empirical issue which has been received little attention in the contemporary finance literature: To identify any financial determinants of the profitability indices for the firms belonging to the Korean chaebol. Three hypotheses of concern were postulated and tested for the sample firms covering the periods of the pre-and post-financial global crises. Regarding the results on the 1st hypothesis test of characterizing any financial profiles for the firms (belonging to the chaebols) by estimating a legitimate panel data model: the present study found the statistically significant relationships of the explanatory variables (BVLEVl, MVLEVl, MV/BV, RISK, FCFF and FOS) with the book-value based profitability ratio: while the market-valued profitability index was explained only by BVLEV2. Regarding the 2nd hypothesis test for the profitability of the sample firms at the industry level: the chaebol firms in the chemical and the food industries overall positioned themselves into the top ranks in order, which was tested by the ANCOVA and the Tukey multiple comparison procedure. Finally: on the 3rd hypothesis test for the 'adjusted' Dupont system, only two such as the 'operating margin' and the 'asset turnover' showed their significant effects between the chaebol firms and their counterparts in both the (parametric) independent samples t-test and the (nonparametric) Wilcoxon-Mann-Whitney statistics.

• Informatization Policy
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• v.22 no.4
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• pp.68-90
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• 2015

This study aims, to review and analyze the trend of the paradigm shift of government innovation focused on the relation between government and citizens. This paper tries to analyze the effects and performance of government innovation through the government 3.0 model, which is highlighted in Korea. This paper chooses higher-education loan programs as the case to study and analyzes results using government innovation theories. Especially, this paper re-organizes Korea's higher-education loan programs with 'Government 3.0 model'. We can expect 'Government 3.0 model'is usefull when explaining the specific policy program innovation loan. Lastly, this paper looks, at improvement points in Korea's higher-education loan programs.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.2
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• pp.89-96
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• 2015

This paper presents a high efficiency, PSM/DCM/CCM triple mode boost DC-DC converter for mobile application. This device operates at Pulse-Skipping Mode(PSM) when it enters light load, and otherwise operate the operating frequency of 1.4MHz with Pulse-Width Modulation(PWM) mode. Especially in order to improve the efficiency during the Discontinuous-Conduction Mode(DCM) operation period, the reverse current prevention circuit and oscillations caused by the inductor and the parasitic capacitor to prevent the Ringing killer circuit is added. The input voltage of the boost converter ranges from 2.5V ~ 4.2V and it generates the output of 4.8V. The measurement results show that the boost converter provides a peak efficiency of 92% on CCM and 87% on DCM. And an efficiency-improving PWM operation raises the efficiency drop because of transition from PWM to PFM. The converter has been fabricated with a 0.18um Dongbu BCDMOS technology.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.4
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• pp.212-219
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• 2017

To become a person that is suitable to the 'High-Touch' generation where emotion takes over, we can focus on 6 skill including design, story, harmony, empathy, play, and meaning. Among these skills, harmony with design was chosen as the most important skill. Design can be seen as the basic element of all business, but it will be difficult to match the flow of the future Sensibility and intuitive generation with just the modern design that has been made based on reasonable and objective information and knowledge. This study suggests system and standardization of Sensibility surface processing design that satisfies great quality, attractive quality and Sensibility quality by applying surface processing design of product and Sensibility cognitive factors felt by the consumer by setting differentiated strategy and CMF (Color, Material, Finishing) understanding along with the importance of design materials in primary aspect. By considering the efficacy/characteristic of new surface processing characteristic/differentiation/possibility of implementation according to setting direction of differentiated CMF strategy per type of parts applied to the product, visual surface processing sample was implemented. Through this, it is expected that practical communication connected tool and Sensibility surface processing design's strategic access framework can be applied by understanding and sharing comprehensive elements such as target product, part type, applied material, applied surface processing, surface color, surface texture, and implementing feeling to environments such as designers, CMF designers, surface processing experts, and engineers in IT, electronics, and other areas. when developing a product.