• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.5
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• pp.370-374
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• 1991

A high performance fully ion-implanted InP JFET was characterized for high speed switching elements. The switch has an insertion loss of 5.5dB with 31.6dB isolation at 1GHz. This device can effectively swithc a byte-multiplexed 2Gb/s signal and an eye-diagram taken at 2Gb/s shows an error-free eye pattern. Therefore, this device can be used as a switching element for high transmission data rate for monolithic integration of optoelectronic circuit in the long-wavelength region.

• The KIPS Transactions:PartD
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• v.17D no.2
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• pp.129-146
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• 2010

Nowadays, XML has been favored by many companies internally and externally as a means of sharing and distributing data. there are many researches and systems for modeling and storing XML documents by an object-oriented method as for the method of saving and managing web-based multimedia document more easily. The representative tool for the object-oriented modeling of XML documents is UML (Unified Modeling Language). UML at the beginning was used as the integrated methodology for software development, but now it is used more frequently as the modeling language of various objects. Currently, UML supports various diagrams for object-oriented analysis and design like class diagram and is widely used as a tool of creating various database schema and object-oriented codes from them. This paper proposes an Efficinet Query Modelling of XML-GL using the UML class diagram and OCL for searching XML document which its application scope is widely extended due to the increased use of WWW and its flexible and open nature. In order to accomplish this, we propose the modeling rules and algorithm that map XML-GL. which has the modeling function for XML document and DTD and the graphical query function about that. In order to describe precisely about the constraint of model component, it is defined by OCL (Object Constraint Language). By using proposed technique creates a query for the XML document of holding various properties of object-oriented model by modeling the XML-GL query from XML document, XML DTD, and XML query while using the class diagram of UML. By converting, saving and managing XML document visually into the object-oriented graphic data model, user can prepare the base that can express the search and query on XML document intuitively and visually. As compared to existing XML-based query languages, it has various object-oriented characteristics and uses the UML notation that is widely used as object modeling tool. Hence, user can construct graphical and intuitive queries on XML-based web document without learning a new query language. By using the same modeling tool, UML class diagram on XML document content, query syntax and semantics, it allows consistently performing all the processes such as searching and saving XML document from/to object-oriented database.

• Journal of the Korea Society of Computer and Information
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• v.18 no.2
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• pp.165-174
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• 2013

Depending on point of view, a service can be defined as interactions between customers and service providers or service delivery processes or customer's experiences. To develop and design a new service, the most of approaches presented in the previous researches represent a service mainly by the interactive activities or functions between customers and providers. The critical features of services which differentiate services from physical products are the inseparability that production and consumption occur at the same time and the heterogeneity that each customer ask their requirements to providers. To reflect the characteristics on the service model, we have to include contextual features in the service model. For the purpose, we define a service as the process of solving the customer's problems and a service is structured into three components: contacts, informations, and activities. We suggest the job mapping diagram to model a service process by the three components and then apply it to a hotel service process and compare the result with it of a blueprint.

• Journal of Korean Society of Transportation
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• v.23 no.1
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• pp.93-102
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• 2005

An Origin-Destination (O/D) is considered as one of the important information in route choices and trip assignments. A household interview survey is deemed to be the traditional and the most widely used method in making sample O/D and its conversion to the total O/D. Some researchers have studied to estimate dynamic O/D from the relationship between link volumes and trip assignment model. Nowadays, owing to the recent rapid spread of cellular phones. Location information of the cellular phone through the Base Station(BS) is considered as an alternative to O/D estimation. In this study, the methodology of generating BS-based O/D and the methodology of converting this O/D into an administrative district-based O/D are proposed. The information of GPS positions and cellular BS positions have acquired by establishing GPS equipment and cellular phone on taxies in Cheongju. Three weeks data are collected and used in estimating O/D by matching them on a digital map. Scatter diagram and sample correlation coefficients are used to investigate the similarity of the GPS-based O/D pattern among weeks, among days, and among times in day. The results show that there are few significant differences among weeks. But there is a difference in O/C pattern between weekday and weekend. Furthermore, there is a difference between morning peak and afternoon peak. Two methodologies are proposed to convert BS-based O/D into an administrative district-based O/D. The first one is to use the distribution pattern of GPS coordinates, the other is to use the coverage area of the BSs. To validate such converted O/D, GPS O/D is used as a true value. The statical analyses through scatter diagram, MAE and RMSE shows that there is few significant defference of pattern between the estimated BS-based O/D and GPS O/D. In the case of using only cellular information, the methodology using coverage area of the BSs is recommended for estimating O/D.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2055-2057
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• 2003

This paper describes the results of RBD(Reliability Block Diagram) analysis of control rod control system, which is being developed as part of KNICS project. The results of RBD indicate unavailability of control cabinet for control rod control system. A purpose of RBB is to evaluate unavailability of control cabinet, identify the design drawbacks of control cabinet, and propose design improvement to a designer to help design the more reliable control rod control system. This RBD defines the logical interaction of failure within a system.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.10
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• pp.763-766
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• 2010

By improving the conducting process of metal source/drain (S/D) in direct contact with the channel, schottky barrier metal-oxide-semiconductor field effect transistors (SB MOSFETs) reveal low extrinsic parasitic resistances, offer easy processing and allow for well-defined device geometries down to the smallest dimensions. In this work, we investigated the arrhenius plots of the SB MOSFETs with different S/D schottky barrier (SB) heights between simulated and experimental current-voltage characteristics. We fabricated SB MOSFETs using difference S/D metals such as Cr (${\Phi}_{Cr}$ ~4.5 eV) and Ni (${\Phi}_{Ni}$~5.2 eV), respectively. Schottky barrier height (${\Phi}_B$) of the fabricated devices were measured to be 0.25~0.31 eV (Cr-S/D device) and 0.16~0.18 eV (Ni-S/D device), respectively in the temperature range of 300 K and 475 K. The experimental results have been compared with 2-dimensional simulations, which allowed bandgap diagram analysis.

• Structural Engineering and Mechanics
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• v.69 no.5
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• pp.499-509
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• 2019

While the wheel flat is an asymmetrical phenomenon in the railway, majority of researches have used two-dimensional models in the investigation of the effect of wheel flat on the wheel rail forces. This is due to the considerably low computational costs of two dimensional (2D) models although their reliability is questionable. This leaves us with the question of "what is the optimum modeling technique?". It is addressed in this research. For this purpose, two and three dimensional numerical models of railway vehicle/track interaction were developed. The three dimensional (3D) model was validated by comparisons of its results with those obtained from a comprehensive field tests carried out in this research and then, the results obtained from the 2D and 3D models were compared. The results obtained indicate that there are considerable differences between wheel/rail forces obtained from the 2D and 3D models in the conditions of medium to large wheel-flats. On the other hand, it was shown that the results of the 2D models are reliable for particular ranges of vehicle speed, railway track stiffness and wheel-fats lengths and depths. The results were used to draw a diagram, which presents the optimum modeling technique, compromising between the costs and accuracy of the obtained results.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.12
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• pp.71-79
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• 2013

This paper describes a 12.5 Gb/s low-power receiver design with equalizer adaptation. The receiver adapts to channel and chip process variation by adaptation circuit using sampler and serializer. The adaptation principle is explained. It describes technique receiving ground referenced differential signal of voltage-mode transmitter for low-power. The CTLE(Continuous Time Linear Equalizer) having 17.6 dB peaking gain to remove long tail ISI caused channel with -21 dB attenuation. The voltage margin is 210 mV and the timing margin is 0.75 UI in eye diagram. The receiver consumes 0.87 mW/Gb/s low power in 45 nm CMOS technology.

• Resources Recycling
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• v.14 no.5 s.67
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• pp.18-23
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• 2005

Recovery of phosphoric acid from waste acid mixture of acetic, nitric and phosphoric acid has been attempted by using solvent extraction method. In this work, organic phosphate was used as an extraction agent. The effect of phosphate concentration, agitation speed and time on the solvent extraction of acetic and nitric acids has been investigated. The optimum concentration of phosphate for preferential extraction of acetic and nitric acids from waste acid was found to be about 50% irrespective of agitation speed and time. Purified phophoric acid was recovered from extraction residue at 1/3 of A/O ratio and 6th stage of extraction stage, which is well consistent with the value calculated by using McCabe-Thiele diagram.

• Transactions of Materials Processing
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• v.26 no.3
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• pp.144-149
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• 2017

In order to characterize the macroscopic mechanical response of ultra-thin (0.1 mm thick) ferritic stainless steel sheet at various loading paths, a crystal plasticity finite element method (CP-FEM) was introduced. The accuracy of the prediction results was validated by comparing with the experimental data. Based on the results, the forming limit diagram (FLD) was predicted using a modified Marchinicak-Kuczinski model coupled to a non-quadratic anisotropic yield function, namely, Yld2000-2d. The predicted FLD was found to be in good agreement with the experimental data.