• Journal of the Korean Society for Heat Treatment
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• v.2 no.2
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• pp.68-83
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• 1989

Physical metallurgy aspects of gaseous ferritic nitrocarburising are reviewed in the light of basic studies undertaken since 1975 which have illustrated inconsistencies between the iron-carbon-nitrogen ternary phase diagram at $570^{\circ}C$ and the experimental observation of the co-existence of the ${\varepsilon}$ carbonitride phase and ferrite. Thermodynamic investigations by Xu and Li together with those by Slycke et al are reviewed to illustrate compatability between a modified isothermal section of the Fe-C-N system and the formation and growth of a monophased ${\varepsilon}$ structure under a variety of processing conditions. The implications of the modified diagram in terms of innovations in industrial ferritic nitrocarburising practice are discussed, together with limitations on the control of the process. The importance of the developing technology of black nitrocarburising for enhanced wear, fatigue, and corrosion resistance is emphasised. Basic studies and industrial status of austenitic nitrocarburising treatments are also reviewed, which highlight the importance of substrate strengthening for high load bearing applications of anti-scuff thermochemical treatments.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.7
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• pp.856-863
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• 1999

The thermal performance degradation of heat pipes is caused by the non-condensable gas generation mainly due to the electrochemical corrosion which results from the reaction of working fluids with tube materials. In this study, a simplified method described below was proposed to estimate the life of heat pipes concerning the non-condensable gas generation. The temperature distributions at the outer surface of heat pipes was measured, and based on them the amount of non-condensable gas of hydrogen was estimated. Applying it to the Arrhenius model, the mass generation of hydrogen and the volume occupied by the gas In heat pipes could be estimated for an operating temperature and time. Moreover, this simplified method was applied to the accelerated life test of nine methanol-stainless steel heat pipe samples.

• KSBB Journal
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• v.10 no.5
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• pp.547-552
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• 1995

Some functional and rheological properties of the ${\gamma}$-polyglutamic acid(${\gamma}$-PGA) produced from alkalophilic Alcaligenes sp. were investigated. Viscosity synergism with thickening agents, capacities for gelling, entrapig of heavy metals, and flocculability of ${\gamma}$-PGA were not observed, but the relatively good compatability with various polyvalent metallic ins, excellent absorption ability and spinability were observed. The ${\gamma}$-PGA solution showed non-Newtonian flow behavior and exhibited pseudoplastic property with a yield stress at above 1% concentration. The values of flow index for 1% solution were in the range of 0.41∼0.75 showing shear rate dependency and the value of yield stress was 2.28 Pa. The value of consistency index was 0.868 Pa$.$Sn and was exponentially dependent on concentration.

• Proceedings of the Korean Society of Crop Science Conference
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• 1998.10a
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• pp.368-390
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• 1998

It is urgent and of great importance for us to integrate and systemize the agricultural Information system available in Korea. In order to modernize the new Korean agricultural information system, which is enable to enhance compatability of domestic agricultural production system to those of abroad, and to be ready for the era of information and communication, every individual effort and progress is to be evaluated and systemized based on an integrated network system. In this study a comprehensive review for the present status of the Korean agricultural information system was made, and to prohibit the progress and development of this sector were the barriers identified. A survey was carried out to assess specific agricultural information demanded by local farmers. For the efficient utilization of the local agricultural information, the role of agricultural colleges was emphasized.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.375-377
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• 2007

The purpose of this study was to investigate total $CO_2$ amount of steel and reinforced concrete construction, and compare and analyze $CO_2$ amount on construction-material. And then it was studied about new element that environment compatibility of architecture structure design based on paradigm of environment age. Architecture action should have proceeded course that reduce burden of the earth environment in relation between architecture and environment and increase contact of human and nature. As environment compatibility development is emphasized with architecture development, architecture structure design give improvement of one important element that environment compatibility except stability, function, economy and necessary propriety of environment compatability of construction design.

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.61-78
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• 2015

This study investigates the differences between IT workers, who possess a high understanding of technology, and non-IT workers in the resistance to accepting an innovative service like mobile commerce. From a total of 317 survey respondents, the results of the study revealed that perceived risk, compatability, and complexity were the significant factors for resistance to mobile commerce for IT workers, while relative advantage, compatibility, and complexity were the factors of resistance for non-IT workers. Higher innovation resistance was shown to result in lower intention of use for both groups of mobile commerce users.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1948_1949
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• 2009

All the power generating station require dc auxiliary power systems to operate those dc components that must be available if a loss of ac power occur. Some examples of such components are auxiliary motors, circuit breakers, relays and solenoids. The dc source may be one common battery for both power and control or two separate batteries; one for power and another for control. Typically, a dc auxiliary power system is designed as an ungrounded system, instead of grounded system, so that a low-resistance ground fault on one of its two polarities will not affect the operation of the system, thus increasing system reliability and continuity of service. A ground detector should provide a high polarity-to-ground resistance so that a single ground fault occurring on the system will not affect the operation of that system. Sensitive relays have been known to energize momentarily while the cable and capacitive charge to ground shifts[1]. A power station had experienced this kind of incident and performed root cause analysis based on PC based simulation program known as PSpice. This simulation showed adapted relays on the system energize momentarily and design criteria on this relay should be corrected.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.1
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• pp.1-10
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• 1998

Relationships between TSP and PM10 concentrations were evaluated using their respective data sets collected from Taegu and Kyeungsan areas during the period of December 1993 to November 1994. The collection of data was made using the gravimetric and $\beta$-ray absorption ($\beta$-MPM) methods for 7 days of every month from three urban sites in Taegu and one suburban site in Kyeungsan. Correlation coefficients between TSP and PM10 concentrations for these four sampling sites were found in the range of 0.85 $\sim$ 0.96. Correlation analysis was also conducted for $\beta$-PM concentration data that were measured only from the residential and commercial sites. The correlation coefficients between TSP and $\beta$-PM concentrations were 0.9 in the residential site and 0.8 in the commercial site. By contrast, the correlation coefficients between PM10 $\beta$-PM concentrations were almost identical for both the residential and commercial sites with a value of 0.88. The mean ratio for PM10 to TSP concentrations for all sites was appeared to be 0.68. The analysis of seasonal trends in PM10/TSP ratios showed that the contribution of PM10 to TSP concentrations was more significant during winter (0.70 $\sim$ 0.75) than during summer (0.61 $\sim$ 0.68). The results of this study may provide empirical informations on the compatability of aerosol data measured by different sampling methods.

• Journal of Broadcast Engineering
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• v.15 no.6
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• pp.868-875
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• 2010

AT-DMB was developed to raise the transmission rate of existing T-DMB with backward compatability. The transmission and hierarchical video service technique were legislated as Korean TTA standards, and other application service techniques including data services are being developed for the commercial service. In this paper, we consider the power of transmission power level of signals in Advanced Terrestrial Digital Multimedia System according to the constellation ratio. And we propose a new scheme for normalization of transmission signal power level in AT-DMB system. Adopting this scheme, the signal power level of hierarchical modulated signal can be uniform in AT-DMB system both for B Mode and Q Mode.

• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.625-632
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• 2003

We are view of the information on VPN(Virtual private Network) into each difference layer protocol. network on mutuality exchanged of information is importance of the confidentiality and Integrity. But it is presented problems about compatability and availability between variable equipment as several protocol. hence, it was achieved of the transmission through encryption and authentication of information, although there is secured an intended attack from the third intruder. so tunneling VPN system on achieving, each layer position transmit of mutuality exchanged. This study will investigate the codification and certified security status when layer2 and layer 3 informations are each transmitted using protocol with integrity Public Key. In addition, we will using protocol and the performance analysis difference between layers and layers.