• Journal of the Korean Society of Combustion
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• v.16 no.2
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• pp.16-22
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• 2011

It is a challenging task to apply large detailed chemical mechanisms of fuel oxidation in simulation of complex combustion phenomena. There exist a few systematic methodologies to reduce detailed chemical mechanisms to smaller sizes involving less computational load. This research work concerns generation of a skeletal chemical mechanism by a directed relation graph with specified accuracy requirement. Two sequential stages for mechanism reduction are followed in a perfectly stirred reactor(PSR) for high temperature chemistry and to consider the autoignition delay time for low and high temperature chemistry. Reduction was performed for the detailed chemical mechanism of n-heptane consisting of 561 species and 2539 elementary reaction steps. Validation results show acceptable agreement for the autoignition delay time and the PSR calculation in wide parametric ranges of pressure, temperature and equivalence ratio.

• The Journal of Information Systems
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• v.28 no.4
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• pp.1-25
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• 2019

Purpose The purpose of this study is to investigate cognitive mechanism of goal relations (Single-goal vs. Multiple-goals) and to-do list (Packing vs. Unpacking) and also verify the role of self-efficacy in the perspective of motivation belief. The perspective of cognitive mechanism is related to the effects of how the relations of multitasking environments affects to facilitating relation or conflicting relations. In pursuit of a single goal, judgement of task importance can be facilitated by unpacking effect due to relations of strongly associated project components including to-do list. On the other hands, in pursuit of multiple goals, judgement of task importance can be conflicted due to mutually exclusive relations of multiple goals. Additionally, the cognitive mechanism can be regulated from the role of self-efficacy, which contributes to motivation belief on how much a person is confident in achieving given tasks. In the end this research is to identify self-efficacy as boundary condition in inhibiting the effects of facilitation and conflict. Design/methodology/approach This study conducted Two-way ANOVA (Packing/ Unpacking * Single-goal/ Multiple-goals) to explore the effects of cognitive mechanism on task importance. After that we performed Three-way ANOVA, 2 (To-do list: Packing/ Unpacking) * 2 (Goal relation: Single-goal/ Multiple-goals) * 2 (Self-efficacy: Low self-efficacy/ High self-efficacy) to verify the role of self-efficacy between goal relations and to-do list. Findings In the cognitive mechanism, the task importance is not significantly different between in packed and in unpacked condition in pursuit of a single goal. But multitasking with multiple goals causes goal conflict, which means packed condition indicates significantly higher task importance than unpacked condition. Additionally, for a group with low self-efficacy unpacking leads to conflicting relation, which implies that packed condition is more efficient strategy than packed condition. On the other hands, in pursuit of mulitple goals, either packing or unpacking has no distinctive effects on task importance. However, participants with high self-efficacy are no longer affected by facilitating relation and conflicting relation as well in pursuit of either a single goal or multiple goals as well.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.3
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• pp.656-671
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• 2015

The purpose of the present study is to examine relationships between disconnection and rejection schema, defense mechanism, and mental health in college students using structural equation modeling. The present study suggested a proposed model in which defense mechanism exerted a full mediating effect on the relation between disconnection and rejection schema and mental health. Goodness of fit tests were used to compare the proposed model against competing models. The subjects consisted of 304 college students. They completed the Young Schema Questionnaire(YSQ-SF), the Defense Style Questionnaire(DSQ), and the Mental Health Scale. The results showed that the second model had a better goodness of fit. Based on these findings, it is suggested that psychological interventions for mental health in college students should consider strategies to use more flexible and more adaptive defense mechanism style.

• Journal of the Korean Society of Combustion
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• v.21 no.3
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• pp.16-23
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• 2016

In this study, skeletal mechanisms are produced by directed relation graph with specified threshold value and sensitivity analysis based on species database from the directed relation graph. Skeletal mechanism is optimized through the elimination of unimportant reaction steps by computational singular perturbation importance index. Reduction is performed for the detailed mechanism of methyl butanoate consisting of 264 species and 1219 elementary reactions. Validation shows acceptable agreement for auto-ignition delays in wide parametric ranges of pressure, temperature and equivalence ratio. Methyl butanoate has been proposed as a simple biodiesel surrogate although the alkyl chain consists of four carbon atoms. The resulting surrogate mechanism for n-heptane and MB consists of 76 species and 226 reaction steps including those for NOx.

• Korean Journal of Oriental Medicine
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• v.4 no.1 s.4
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• pp.47-62
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• 1998

We explicate the forming mechanism of Sasang constitution as the principle of energy distribution which is based on the evolutionary hypothesis. The result was obtained as follows: 1. The principle of form-image (形象) in oriental medicine can be explained with the relation between structure and function that a life acquires through the adaptation and evolution. 2. The Sung-jung (性情) in Sasang constitutional medicine can be explained as the strategy for survival or the pattern of adaptation by which an individual or a species lives in this world. 3. The forming mechanism of Sasang constitutional organic phase (臟局) can be explained as the principle of energy distribution which includes three hypothesis (hypothesis of limited resources, hypothesis of preference and hypothesis of effectiveness). 4. It is postulated that the local hemodynamics is one of the most important factors that determine the difference of Sasang constitutional organic function. 5. The relation of metabolic rate, local hemodynamics and thermo-metabolism is inseparable and it is the important point of forming mechanism of Sasang constitution and the diagnosis of pulse.

• Journal of the Korean Society for Railway
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• v.6 no.4
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• pp.294-299
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• 2003

Using a conventional railway, a tilting train was applied as a means of improving vehicle speed during curve negotiation without any modification of infrastructure. As a study for the optimum design of the tilting mechanism of a tilting vehicle, the kinematics sensitivity of the tilting mechanism was analyzed. Using the geometric relationship of the linkage-type tilting mechanism, the relationship of the parameters and the performance index was defined using nonlinear algebraic equations. With the defined relation, the effect of change in the parameters on the performance was analyzed. The analysis result can be used in the optimum design of a tilting mechanism that considers the track environment, vehicle and operational condition in which the tilting vehicle is applied.

• Korean Journal of Computational Design and Engineering
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• v.21 no.4
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• pp.433-442
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• 2016

This paper aims to define the relational logic of in-between code articles as well as within atomic sentences in Korean Building Code, as an intermediate research and development process for the automated building permit system of Korea. The approach depicted in this paper enables the software developers to figure out the logical relations in order to compose KBimCode and its databases. KBimCode is a computer-readable form of Korean Building Code sentences based on a logic rule-based mechanism. Two types of relational logic definition are described in this paper. First type is a logic definition of relation between code sentences. Due to the complexity of Korean Building code structure that consists of decree, regulation or ordinance, an intensive analysis of sentence relations has been performed. Code sentences have a relation based on delegation or reference each other. Another type is a relational logic definition in a code sentence based on translated atomic sentence(TAS) which is an explicit form of atomic sentence(AS). The analysis has been performed because the natural language has intrinsic ambiguity which hinders interpreting embedded meaning of Building Code. Thus, both analyses have been conducted for capturing accurate meaning of building permit-related requirements as a part of the logic rule-based mechanism.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.501-505
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• 2016

In this study, a robot is implemented in H/W based on four-bar linkage mechanism and Jansen mechanism. Our goal is to finish the given path using given terms. The various programs was used to understand the mechanism in more detail. DISON m.Sketch, EDISON Designer, Theo Jansen Mechanism Optimization Solver. Using these programs, we can design the robot in more dtails and reduce errors and trials. For the design and implementation of a robot, it is need to get joint variable, a foot point, and their relation. Thus, the proposed kinematic analysis is very important process for the design and implementation of legged robots.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.12
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• pp.1687-1696
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• 1995

An integrated fault diagnosis system for heterogeneous manufacturing environments is developed. This system has a contrast with existing diagnosis systems in the respect that they are mostly for diagnosing faults on individual machines. In addition to the usual (e.g., audio, electrical) diagnostic signals, the characteristics of products from the machines are considered as the unifying diagnostic parameters among heterogeneous machines in the diagnosis. The system is composed of a knowledge representation scheme and a diagnostic query processing mechanism. Its knowledge representation scheme allows the diagnostic knowledges from heterogeneous unit diagnostic systems to be uniformly expressed in terms of the causal relations among relevant data items. It is flexible in the sense that causes for one relation can be effects for another may be reflected on our knowledge representation scheme. The diagnosis mechanism is based on a probabilistic inferencing method. This probablistic diagnosis mechanism provides more general diagnosis than existing ones in that it accommodates multiple causes and takes complication among causes into account. These scheme and mechanism are applied to a typical example to demonstrate how our system works.

• Journal of Photoscience
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• v.9 no.2
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• pp.150-153
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• 2002

Solar UV light is a well-known carcinogen. UVA radiation is probably carcinogenic to humans. In addition, recent investigations point to the importance of UVA irradiation in the photoaging. We investigated the mechanism of sequence- specific DNA damage using $\^$32/P-Iabeled DNA fragments in relation to carcinogenesis and aging. Furthermore, we investigated whether UVA accelerates the telomere shortening in human WI-38 fibroblasts. The exposure of double- stranded DNA fragments to 365 nm light in the presence of endogenous sensitizers produced sequence-specific cleavage at the 5' site of 5'-GG-3' and 5'-GGG-3' sequences. In addition, HPLC analysis revealed that sensitizers plus 365 nm light increased the 8-oxodG content of double-stranded DNA. We discuss the mechanisms of guanine-specific DNA damagecaused by excited photosensitizers in relation to carcinogenesis and aging.