• Journal of Korean Institute of Industrial Engineers
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• v.20 no.1
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• pp.39-51
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• 1994

Almost all accelerated life tests assume that no basic failure mechanism changes within the test stresses. But accelerated life test, considering failure mechanism changes, is needed since failure mechanism changes when accelerating beyond the used stress. This paper studies the analysis when the failure mechanism changes within the test stresses. The piecewise linear regression, which the join point of two lines is estimated, is applied In particular, two accelerated life tests, with and without a change in failure mechanism are examined.

• Analyses & Alternatives
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• v.1 no.2
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• pp.44-64
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• 2017

From the field survey of the main ethnic minority areas in the south China, it is found that political, economic, cultural and natural environmental changes are the main reasons leading to the change of customary law. The power mechanism of the customary law change include the three aspects, such as the promotion of country elite, the dominance of grassroots government, and the daily demands of the villagers, which promote the change of customary law alone or together. Through the application of customary law, the country elites can adjust and refine the rules of customary law in order to make out the new customary law and promote its development. In the current pattern of rural governance, grassroots self-government is actually the "official supervision of people's autonomy". The executive power of the grassroots government often intervene the practice of customary law and other informal rules. This is another mechanism of customary law change. Customary law arises from the practice of the daily life of the villagers. If the villagers think that the norms of customary law cannot meet the actual needs of daily life practice, the customary law will be promoted in the form of collective consultation. This is the most important dynamic practice mechanism of customary law change. Transformation and abandonment are the two ways to change customary law. No matter what kind of change does not lead to the demise of the customary law system, the demise of the customary law is only an outdated result, which is made by the universality, nature and objectivity of customary law. The procedure of customary law change is the process of continuation and rebirth about customary law. The result of the change is to produce the new customary law of keeping pace with the times, and the customary law will be presented with new content and form after the change. The continuation of customary law means the inheritance of traditional customary law, but it is based on the transformation of traditional customary law. The rebirth of customary law means that the traditional customary law is completely discarded. But it will produce new customary law rules and be based on the needs of social life practice. Customary law occupies a pivotal position in the normative system and the national law cannot be replaced. The purpose of customary law change will let the customary rules better adapt to the development of modern society, adjust the social relations more reasonably and better meet people's needs of production and life, which is decided by the character of customary law.

• The Korean Journal of Ceramics
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• v.5 no.1
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• pp.35-39
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• 1999

For many years, alkali activated blast furnace slag cement containing no ordinary portland cement has received much attention in the view of energy saving and its many excellent properties. We examined the structural change of slag glass which was activated by alkali metal compounds using IR spectroscopy. The properties of hydrated products and unhydrated slag grains was characterized by XRD and micro-conduction calorimeter. Ion concentration change in the liquid during the hydration of blast furnace slag was also studied to investigated the hydration mechanism.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.569-570
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• 2007

• Journal of the Korean Ceramic Society
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• v.33 no.4
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• pp.379-384
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• 1996

The H2S sensing mechanism of CuO-SnO2 was confirmed by analyzing the electrical-resistance variation with temperature under an H2S atmosphere. While the resistance of CuO-SnO2 thick film at N2+H2S atmosphere was almost invariant with change in temperature it increased with increasing temperature for air +H2S atmos-phere. This behavior was analyzed using an equation derived from a basic assumption based on the H2S sensing mechanism proposed before. the experimental results are sufficiently explained with the equation derived which showed that the H2S sensing mechanism was reasonable. The equation also gave a detailed analysis and physical meaning to the behavior of the resistance variation with change in H2S concentration.

• Asian Journal of Innovation and Policy
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• v.9 no.1
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• pp.36-55
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• 2020

Climate change is one of the most discussed issues in international for a today. Evaluating the effect of climate change at a regional level and setting up an appropriate policy to address the issues associated with climate change require a proper evaluation process on the climate change and adaptation projects already implemented. Although various evaluation approaches to climate change adaptation programs have been proposed, it is rare to find a proper systematic approach to evaluating the reliability of those climate change adaptation programs. In the current situation regarding the system to evaluate climate change adaptation programs, the purpose of this study is to suggest a theoretical and standardized evaluation system on the reliability of climate change adaptation schemes. The new approach suggested in this paper will be appropriate when requiring a confidence level for adaptation programs that are specially localized and categorized. Using various quantitative and qualitative evaluation methods with the inherent reality mechanism, we provide a conceptual framework to measure the reliability of climate change adaptation programs with a flexible adjustment process. With the proposed framework, it is possible to provide the level of confidence on the results collected from the evaluation systems and construct a standardized, system-wide assessment procedure toward climate change adaptation policies. By applying this approach based on scientific evidence on the reliability of climate change adaptation policies, appropriate and efficient climate change adaptation programs will be properly designed for and implemented in Korea.

• The Journal of Korean Academy of Prosthodontics
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• v.27 no.1
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• pp.123-141
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• 1989

The purpose of this study was to investigate the tendency of color change of ceramic, and its mechanism un der the influence of Pd-Ag alloy. The specimens were made by firing porcelain on tile metal plates cast with Au-Pt alloy, Pd-Cu alloy and Pd-Ag alloy. In the case of Pd-Ag alloy, specimens were fired under three different conditions as follows, 1) without protection, 2) protection with ceramic metal conditioner, 3) protection with carbon block. For the specimens of element analysis, a barrier was constructed with platinum foil between metal plate and ceramic. Color change was measured with colorimeter and elemental changes in ceramic were calculated with DC argon plasma emission spectrophotometer. The results were as follows : 1. Color change of ceramic by Pd-Ag alloy was negligible in hue, but decreased in value and increased in chroma (yellow discoloration). 2. Color change of ceramic by Pd-Ag alloy was appeared through vapor transport mechanism. 3. As the protection method for the color change of ceramic by Pd-Ag alloy, application of ceramic metal conditioner was superior to utilization of carbon block.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.14-23
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• 2018

The effect of dodecylbenzene sulfonic acid (DBSA) with different addition amount of DBSA ($M_{DBSA}$), temperatures and solvent-to-oil ratio (SOR, v/v) on asphaltene aggregation in a solvent deasphalting system was investigated. Increasing the $M_{DBSA}$ at SOR 10 and $55^{\circ}C$ caused the asphaltene removal ratio (ARR) to increase first, then maximize at 1 wt% of $M_{DBSA}$ and then decrease continuously. Based on the SARA (saturate, aromatic, resin, asphaltene) composition, the adsorption amount of DBSA on the asphaltene surface and the self-aggregation of the DBSA, the reason for the change in ARR with $M_{DBSA}$ was found due to the adsorption mechanism. In addition, the asphaltene-resin-DBSA colloidal size confirmed the change of adsorption behavior between the asphaltene and DBSA. Based on the results of this study, a hypothetical adsorption mechanism of DBSA on asphaltene aggregation in the solvent deasphalting system was conceived of and proposed.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06d
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• pp.124-126
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• 2006

Mobile Ad hoc networking is an emerging technology and in these days many applications are being developed to run on these networks. In these networks lookup services are very important because all nodes do not have same resources in term of memory and computing power. Nodes need to use different services offered by different servers. Reliable and efficient scheme should be available for lookup services due to limited bandwidth and low computing power of devices in mobile ad hoc networks. Due to mobility and rapid change in network topology, lookup mechanism used in wired network is not appropriate. Service discovery mechanism can be divided into two main categories Centralized and Distributed. Centralized mechanism is not reliable as there is no central node in these networks. Secondly centralized mechanism leads toward single point failure. We can handle the service discovery mechanism by distributing server's information to each node. But this approach is also not appropriate due to limited bandwidth and rapid change in network. In this paper, we present reliable lookup service scheme which is based on distributed mechanism. We are not using replication approach as well due to low bandwidth of wireless networks. In this scheme service discovery mechanism will be handled through different lookup servers. Reliability is the key feature of our proposed scheme.

• Journal of Powder Materials
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• v.7 no.4
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• pp.237-243
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• 2000

The property and performance of the $Al_2O_3/Ni$ nanocomposites have been known to strongly depend on the structural feature of Ni nanodispersoids which affects considerably the structure of matrix. Such nanodispersoids undergo structural evolution in the process of consolidation. Thus, it is very important to understand the microstructural development of Ni nanodispersoids depending on the structure change of the matrix by consolidation. The present investigation has focused on the growth mechanism of Ni nanodispersoids in the initial stage of sintering. $Al_2O_3/Ni$ powder mixtures were prepared by wet ball milling and hydrogen reduction of $Al_2O_3$ and Ni oxide powders. Microstructural development and the growth mechanism of Ni dispersion during isothermal sintering were investigated depending on the porosity and structure of powder compacts. The growth mechanism of Ni was discussed based upon the reported kinetic mechanisms. It is found that the growth mechanism is closely related to the structural change of the compacts that affect material transport for coarsening. The result revealed that with decreasing porosity by consolidation the growth mechanism of Ni nanoparticles is changed from the migration-coalescence process to the interparticle transport mechanism.