• Journal of IKEEE
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• v.15 no.1
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• pp.43-48
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• 2011

Decision problem called an optimal release policies, after testing a software system in development phase and transfer it to the user, is studied. The infinite failure non-homogeneous Poisson process models presented and propose an optimal release policies of the life distribution applied extreme distribution which used to find the minimum (or the maximum) of a number of samples of various distributions. In this paper, discuss optimal software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement. In a numerical example, extreme value distribution as another alternative of existing the Poisson execution time model and the log power model can be verified using inter-failure time data.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.97-106
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• 2019

This study was conducted to propose a reasonable requirement regulation of barrier system of rubble mound revetment offshore landfill for preventing contaminant leakage. The barrier is composed with bottom layer and side barrier. The bottom layer was assumed as impermeable clay layer and side barrier was composed with HDPE sheet (primary element) and mid-protection layer (supplementary element). Seepage-advection-dispersion numerical analysis has been conducted using SEEP/W and CTRAN/W programs under steady flow. As the results, the minimum required barrier regulations for hydraulic conductivity and thickness of the bottom layer were suggested. For side barrier, the extended length of HDPE sheet and the hydraulic conductivity of mid-protection layer were also suggested.

• Journal of Arbitration Studies
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• v.27 no.2
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• pp.121-142
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• 2017

A study on the global trend of accreditation for mediators implies many important aspects of controlling of the quality of mediation. Firstly, whether or not having an accreditation system, most European countries and the U.S. have a common understanding on the fact that mediators need to be trained to mediate disputes, apart from their own expertise on the subject matters. Secondly, private-led accreditation has been utilized in countries having a Anglo-American law system such as the United Kingdom and the U.S. a while nation-managed one has been operated in the countries having a continental law system such as Austria, Belgium, Italy and Germany. Thirdly, private mediation service providers (usually institutions or companies) play an active role in the training and accreditation of mediators and further make them act as mediators in the disputes referred to them. Fourthly, the countries having a nation-managed accreditation system usually stipulate a certain mediation training and accreditation requirement by law. Fifthly, there is no uniform trend on the minimum hours of training required for accrediting the mediators. Sixthly, mediation training generally focuses on the practical mediation capacity-building, including mediation theory and role-playing, mediation simulations, peer review and supervision. And finally, the mediation theory mainly includes the role of mediator, mediation procedures, mediation communication, negotiation and communication skills, mediation ethics and mediator's code of conduct, etc.

• Journal of the Korean GEO-environmental Society
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• v.1 no.1
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• pp.65-70
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• 2000

Recently, soil-bentonite mixtures are frequently used as impervious liners for waste disposal sites. In the present work, bentonite composite liner systems have been developed by utilizing Korean zeolitic bentonites. The geomechanical properties of the liner systems, such as strength hydraulic conductivity, etc. have also been studied. The laboratory and field test results showed that uniaxial strengths of the system were improved by addition of bentonite and CaO-based additive to the upper and lower layer of the liner systems, respectively. Hydraulic conductivity values measured on field liner systems showed less $1{\times}10^{-3}cm/s$, which is considered to be minimum regulation requirement for waste disposal sites.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.7
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• pp.730-735
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• 2004

This paper describes what brings about DC offset and the impact or the DC offset on the performance or direct-conversion mobile receiver in WCDMA system. The performance degradation of $E_{b}/N_{o}$ due to the DC offset is presented through simulation result. Direct-conversion RF Transceiver which has the function of DC offset control is implemented and then applied to the WCDMA test-bed for the performance evaluation. The receiver performance degradation of $E_{c}/I_{o}$ is evaluated and analyzed by varying DC offset value. The practical test showed the minimum requirement of DC offset value to meet system performance.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.4
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• pp.124-130
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• 2008

Automatic layout decomposition techniques have been developed for double patterning technology (DPT). As CMOS manufacturing process scales down to 45nm and below, lithography resolution needs to be improved. DPT has been proposed to enhance the limitation of conventional lithography, by decomposing the layout design into two masks to relax the minimum spacing requirement. However, it is not always possible to decompose a layout into two masks. We have developed new automatic stitching techniques to resolve this problem. Experimental results show that the suggested techniques are promising in decomposing layouts for DPT.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.532-540
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• 2012

In this study, some considerations have been suggested in developing on-site techniques to evaluate the sensitization of stainless steels. Electrochemical potentiokinetic reactivation (EPR) technique is known to be a candidate tool for field applications since it enables quantitative assessment in reasonable test time, compared to oxalic etching (ditch) technique. The on-site application of the test method imposes additional restrictions on the selection of the test method (for example, minimum surface preparation requirement, insensitivity to testing temperature, etc.). The EPR and etching techniques have been compared in order to sensitization of stainless steel structures. It has been widely reported that the maximum sensitivity in the welded structure of stainless steel is shown at heat-affected zone (HAZ) than weldments with cast structure. In this work, sectioned weldments and external surfaces were investigated to reveal the degree of sensitization by the etching and the results were compared with those of EPR test. The EPR test showed little sensitivity to surface roughness and test temperature.

• Journal of Welding and Joining
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• v.22 no.5
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• pp.26-31
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• 2004

In order to propose the optimum welding condition for field application, the effects of welding heat input and cooling rate at PWHT on the mechanical properties were investigated. Submerged arc welding of 1.25Cr-0.5Mo steel for pressure vessel was conducted at welding heat inputs of 15.2kJ/cm, 30.9kJ/cm, and 44.8kJ/cm, and cooling rates of 184$^{\circ}C$/hr, 55$^{\circ}C$/hr, and 2$0^{\circ}C$/hr at PWHT. From the test results, as the welding heat input increase up to 30.9kJ/cm, the changes of microstructure and impact toughness were small. At the heat input of 44.8kJ/cm, however, toughness decreased obviously due to the coarsening of coarse-grained HAZ and formation of ferrite at bainite grainboundary of weld metal. On the other hand, cooling rates at PWHT did not effect on the changes in microstructure and mechanical properties. Even though tensile strength and impact toughness at all welding conditions of this study were above the minimum specification requirement, it was confirmed that heat input of 30.9kJ/cm was the optimum welding condition to improve welding performance by higher heat input.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.98-100
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• 2005

This paper describes link analysis on the processed data, HRIT (High Rate Information Transmission) and LRIT (Low Rate Information Transmission), for the preliminary design of interface between COMS (Communication, Ocean and Meteorological Satellite) and ground station. At the MODAC (MeteorologicaVOcean Data Application Center), the processed data are transmitted to user station via COMS with normalization and calibration by pre-processing of MI (Meteorological Imager) data. Due to consider satellite as radio relay, overall analysis containing uplink and downlink is needed. Specific link parameters can be obtained with using the outcomes of SRR (System Requirement Review) which was held on 13-14 June 2005, in Toulouse. From the relation between overall link margin and output power of HPA (High Power Amplifier) of MODAC, it is shown that even though the minimum power related with COMS receiving power range is transmitted at MODAC, the obtained link margin of HRIT could be above 3 dB at user station which antenna elevation angle is 10 degree.

• International Journal of Concrete Structures and Materials
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• v.4 no.2
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• pp.97-104
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• 2010

The crushed limestone sand is an abundant material in Tunisia, which induces many environmental problems. Indeed, available stocks of siliceous sand drastically decrease because of its massive use in hydraulic concrete. Some recent research works, carried out in Tunisia, concluded that crushed limestone sand may be used in concrete manufacture instead of siliceous sand traditionally used. In this context, an experimental study was achieved in order to quantify the influence of a partial or total substitution of siliceous sand by crushed limestone sand on hydraulic concrete performances. Preliminary chemical and physical tests on crushed sand indicated that it presented the minimum requirement for its use as aggregate in hydraulic concrete. 79 concretes were then prepared with siliceous sand, crushed limestone sand and a mix of the two sands. Their slump value and compressive strengths were measured on plain concretes. Complementary structural tests on reinforced concrete beam were also performed. The results proved that crushed limestone sand concretes showed workability and mechanical performances closed to those of siliceous sand concretes.