• 제목/요약/키워드: a relation in the mechanism

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직접 관계 그래프(DRG)를 이용한 디젤 연료의 상세 화학 반응 기구 축소화 (Skeletal Chemical Mechanisms for a Diesel Fuel Surrogate by the Directed Relation Graph(DRG))

  • 이영재;허강열
    • 한국연소학회지
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    • 제16권2호
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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.

멀티태스킹 상황에서 업무적 특성과 개인의 자기 효능감을 고려한 효율적인 프로젝트관리 전략 (Effective Project Management Strategy Depending on Individual Self-efficacy and Task Characteristics under Multitasking Situation)

  • 박준영;박도형
    • 한국정보시스템학회지:정보시스템연구
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    • 제28권4호
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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.

단절 및 거절 도식과 정신건강 간의 관계에서 방어기제의 매개효과 (The Mediating Effect of Defense Mechanism in the Relation between Disconnection and rejection Schema and Mental Health)

  • 김행신;서수균
    • 수산해양교육연구
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    • 제27권3호
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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.

Methyl Butanoate의 상세 화학 반응 메커니즘 자동 축소화를 통한 기초 반응 메커니즘의 생성 및 검증 (Chemical Mechanism Reduction and Validation of Methyl Butanoate by Automatic Reduction Procedure)

  • 이영재;허강열
    • 한국연소학회지
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    • 제21권3호
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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.

사상체질성립기전에 대한 이론적 고찰 (A theoretical study on the forming mechanism of Sasang constitution)

  • 지상은;최선미;조황성
    • 한국한의학연구원논문집
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    • 제4권1호통권4호
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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.

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대차 틸팅 기구의 매개변수 분석 연구 (Parametric Study of a Bogie Tilting Mechanism)

  • 김남포;구동회;한형석
    • 한국철도학회논문집
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    • 제6권4호
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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.

인허가관련 설계품질검토 자동화를 위한 건축법규 문장 관계논리에 관한 연구 (Relational Logic Definition of Articles and Sentences in Korean Building Code for the Automated Building Permit System)

  • 김현정;이진국
    • 한국CDE학회논문집
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    • 제21권4호
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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.

이종분산 고장 진단을 위한 지식표현 방법 및 진단 방법의 개발 (Development of a Knowledge Representation Scheme and Diagnosis Mechanism for Heterogeneous Distributed Fault Diagnosis)

  • 안영애;박종희
    • 전자공학회논문지B
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    • 제32B권12호
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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.

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얀센메커니즘을 이용한 로봇 설계 (Design of Robot Using of Jansen Mechanism)

  • 김병진;김현민;이효정
    • EDISON SW 활용 경진대회 논문집
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    • 제5회(2016년)
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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.

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Mechanism of guanine-specific DNA damage by UVA and its role in photocarcinogenesis and photoaging

  • Kawanishi, Shosuke;Oikawa, Shinji;Hiraku, Yusuke
    • Journal of Photoscience
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    • 제9권2호
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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.

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