• 제목/요약/키워드: Internal Model

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Practical modeling and quantification of a single-top fire events probabilistic safety assessment model

  • Dae Il Kang;Yong Hun Jung
    • Nuclear Engineering and Technology
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    • 제55권6호
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    • pp.2263-2275
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    • 2023
  • In general, an internal fire events probabilistic safety assessment (PSA) model is quantified by modifying the pre-existing internal event PSA model. Because many pieces of equipment or cables can be damaged by a fire, a single fire event can lead to multiple internal events PSA initiating events (IEs). Consequently, when the fire events PSA model is quantified, inappropriate minimal cut sets (MCSs), such as duplicate MCSs, may be generated. This paper shows that single quantification of a hypothetical single-top fire event PSA model may generate the following four types of inappropriate MCSs: duplicate MCSs, MCSs subsumed by other MCSs, nonsense MCSs, and MCSs with over-counted fire frequencies. Among the inappropriate MCSs, the nonsense MCSs should be addressed first because they can interfere with the right interpretation of the other MCSs and prevent the resolution of the issues related to the other inappropriate MCSs. In addition, we propose a resolution process for each of the issues caused by these inappropriate MCSs and suggest an overall procedure for resolving them. The results of this study will contribute to the understanding and resolution of the inappropriate MCSs that may appear in the quantification of fire events PSA models.

MEMS 고체 추진제 추력기의 성능예측 및 분석 (Performance Prediction and Analysis of a MEMS Solid Propellant Thruster)

  • 정주영;이종광
    • 한국추진공학회지
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    • 제21권6호
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    • pp.1-7
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    • 2017
  • 내탄도 모델 및 CFD 해석을 통해 MEMS 고체 추진제 추력기의 성능을 예측하고 분석하였다. 노즐목 지름이 $416{\mu}m$, 면적비가 1.85인 추력기의 내탄도 모델 해석 결과, 챔버 압력은 최대 197 bar까지 상승하였으며, 최대 추력은 3,836 mN이었다. CFD 해석에 내탄도 모델의 챔버 압력을 작동압력으로 적용하였으며, 해석 모델을 단열 모델과 열손실 모델로 구분하여 해석을 진행하였다. 해석 결과 점성 효과만이 고려된 단열 모델의 최대 추력은 내탄도 모델에 비해 14.92% 낮았으며, 짧은 작동 시간으로 인하여 열손실에 의한 추력 손실은 매우 작게 나타났다.

귀비탕가미방(歸脾湯加味方)이 고혈압(高血壓) 및 고지혈증(高脂血症)에 미치는 영향(影響) (Experimental study on the effects of Guibitanggamibang on blood pressure and hyperlipidemia)

  • 노진환;문상관;고창남;조기호;김영석;배형섭;이경섭
    • 대한한의학회지
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    • 제18권2호
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    • pp.245-266
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    • 1997
  • In order to study the effects of Guibitanggamibang on blood pressure and hyperlipidemia, experimental study were performed on hypertension in normal and SHR rats, and on hyperlipidemia induced by Triton WR-1339 in normal rats. Also the level of total cholesterol, triglyceride, LDL-cholesterol, HDL-cholesterol, phospholipid and transaminase(GOT, GPT) were measured. The results are summarized as follows: 1. After Guibitanggamibang was given to normal rats, the results showed that inhibitory effects on blood pressure and heart beat were not statistically significant. 2. After Guibitanggamibang was given to SHR rats, the results showed that inhibitory effects on blood pressure were statistically significant. 3. In the model of hyperlipidemia induced by 2% cholesterol food, Guibitanggarrubang had significantly-decreasing effects on total cholesterol, triglyceride, HDL-cholesterol, LDL-choleste rol, Transaminase(GOT, GPT) level in serum. 4. In the model of hyperlipidemia induced by Triton WR-1339, Guibitanggamibang had significantly-decreasing effects on total cholesterol, triglyceride, LDL-cholesterol, phospholipid, Transaminase(GOT, GPT) level in serum. 5. In the model of hyperlipidemia induced by Triton WR-1339, Guibitanggamibang had no significant effects on HDL-cholesterol level in serum. These results show that Guibitanggamibang(歸脾湯加味方) has significant inhibitory effects on blood pressure and hyperlipidemia and that it could be clinically applied for hypertension and hyperlipidemia.

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Expression of Muscarinic Receptors and the Effect of Tiotropium Bromide in Aged Mouse Model of Chronic Asthma

  • Kang, Ji Young;Kim, In Kyoung;Hur, Jung;Kim, Seok Chan;Lee, Sook Young;Kwon, Soon Seog;Kim, Young Kyoon
    • Tuberculosis and Respiratory Diseases
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    • 제82권1호
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    • pp.71-80
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    • 2019
  • Background: Efficacy and safety of tiotropium bromide, a muscarinic receptor antagonist, in treatment of asthma have been reported. However, its effect on airway remodeling in chronic asthma of the elderly has not been clearly verified. The objective of this study was to investigate the effect of tiotropium and expression of muscarinic receptors as its related mechanism in an aged mouse model of chronic asthma with airway remodeling. Methods: BALB/c female mice age 6 weeks, 9 and 15 months were sensitized and challenged with ovalbumin (OVA) for three months. Tiotropium bromide was administered during the challenge period. Airway hyperresponsiveness (AHR) and pulmonary inflammation were measured. Parameters of airway remodeling, and expression levels of $M_2$ and $M_3$ receptors were examined. Results: Total cell with eosinophils, increased in the OVA groups by age, was decreased significantly after treatment with tiotropium bromide, particularly in the age group of 15 months. AHR and levels of interleukin (IL)-4, IL-5, and IL-13 were decreased, after tiotropium administration. In old aged group of 9- and 15-months-treated groups, hydroxyproline contents and levels of ${\alpha}$-smooth muscle actin were attenuated. Tiotropium enhanced the expression of $M_2$ but decreased expression of $M_3$ in all aged groups of OVA. Conclusion: Tiotropium bromide had anti-inflammatory and anti-remodeling effects in an aged mouse model of chronic asthma. Its effects seemed to be partly mediated by modulating expression $M_3$ and $M_2$ muscarinic receptors. Tiotropium may be a beneficial treatment option for the elderly with airway remodeling of chronic asthma.

내부통제시스템 품질과 이익조정과의 관계분석 - 중국 SSE 상장기업을 중심으로 (An Analysis of the Correlation between Internal Control System Quality and Earnings Management - Focused on SSE Listed Co. in China)

  • 쉬멍준;김동일
    • 디지털융복합연구
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    • 제19권2호
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    • pp.51-60
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    • 2021
  • 본 연구에서는 기업 내부통제의 중요성을 토대로 내부통제 품질과 이익조정과의 상관관계 분석을 바탕으로 내부통제 품질과 실제 이익 관리와 이익조정과의 상관관계를 분석하였다. 본 연구을 위해 내부통제 및 이익조정의 개념, 분류, 측정 방법 및 모델을 도입하여 본 논문의 연구가설을 제안하였다. 연구분석에서는 관련 측정 모델을 사용하여 기업의 실제 이익관리 수준과 이익조정 관리 수준을 설명 변수로 투입하여 회귀 모델을 설정하고 분석을 진행하였다. 연구결과, 실증 기업의 내부통제 품질, 실질적인 이익과 이익조정 간에는 통계적으로 유의미한 음의 상관관계가 있음을 확인하였으며, 실증 연구를 통해 최종 결과와 결론을 도출할 수 있었다. 이러한 연구결과는, 향후 내부통제 이론의 발전과 더불어 경영자의 이익조정 행동에 대한 관리 및 통제를 위한 기초적 가이드라인을 제공할 수 있을 것이다.

Model for end-stage liver disease-3.0 vs. model for end-stage liver disease-sodium: mortality prediction in Korea

  • Jeong Han Kim;Yong Joon Cho;Won Hyeok Choe;So Young Kwon;Byung-Chul Yoo
    • The Korean journal of internal medicine
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    • 제39권2호
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    • pp.248-260
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    • 2024
  • Background/Aims: The model for end-stage liver disease (MELD) serves as an indicator for short-term mortality among patients diagnosed with liver cirrhosis (LC) and is used to prioritize patients for liver transplantation. In 2021, the updated version of MELD, MELD-3.0, was introduced to improve the accuracy of the mortality prediction of MELD. Therefore, this study aimed to compare the efficacy of MELD 3.0 and MELD-Na in predicting mortality among Korean patients with LC. Methods: A retrospective review was conducted using the medical records of patients diagnosed with LC who were admitted to Konkuk University Hospital From 2011 to 2021. The study calculated the predictive values of MELD-Na and MELD-3.0 for 3- and 6-months mortality using the area under the receiver operating curve (AUROC) and compared the results using the DeLong test. Results: Of the 3,034 patients enrolled in the study, 339 (11.2%) died within 3 months and 421 (14.4%) died within 6 months. The AUROCs values for predicting 3 months mortality were 0.846 for MELD-Na and 0.851 for MELD-3.0. The corresponding AUROC values for predicting 6 months mortality were 0.843 for MELD-Na and 0.848 for MELD-3.0. MELD-3.0 exhibited better discrimination ability than MELD-Na for both 3 (p = 0.03) and 6 months mortality (p = 0.01). Conclusions: Our study found a significant difference between the performance of MELD-3.0 and MELD-Na in Korean patients with LC.

K-POP의 세계시장 진출 성공요인 분석: VRIO 모형을 중심으로 (Exploring the Success Factors of K-POP Globalization: Utilizing the VRIO Model)

  • 신동석;남성집;남명현
    • 유통과학연구
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    • 제13권2호
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    • pp.55-62
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    • 2015
  • Purpose - This study aims to investigate the success factors pertaining to K-POPs from an analysis of the internal business environment. Much research has investigated Korean Moves or how to popularize them. The research mainly focused on aspects of Korean Moves. However, few studies have attempted to examine Korean Moves or K-POPs from a managerial viewpoint. The current research tries to investigate the success factors of K-POP from strategic perspectives, specifically utilizing internal resource based view perspectives. It differentiates itself by looking at the competitiveness of K-POP from the internal resources. Research design, data, and methodology - In the entertainment industry, where creativity is heavily stressed, competitiveness is often regarded within the organization as a form of intangible asset, knowledge, or technology that is often related with the organization's personnel. Some research has tried to reveal the competitiveness of K-POP using Porter's competitiveness of nations framework. Others utilize the adapted model of Porter's structure. However, these models only look at the outside environment, and not inside a firm's resource, knowledge, or capabilities. This research utilizes the VRIO model to examine the internal resources and capabilities of K-POP producers. The model measures whether a firm's internal resources and capabilities are valuable, rare, difficult to imitate by competitors, or organizable. The research covered businesses whose yearly revenue exceeds $10 Million in music planning and recording in South Korea. There were only thirteen such companies (one percent of the total population). Of these, companies for whom 20 percent or more of the sales revenue comes from the abroad are targeted. Only seven are selected and these participated in the research. In order to find a firm's internal resources, we conducted qualitative research methodology. Their business names and persons who participated in this research are not revealed due to case sensitive issues. Instead, we use unrelated initials for their names and their statements. Results - From the in-depth interview with top-tier K-POP producers and managers, the current research tried to identify resources and capabilities that helped to strengthen their competitiveness. These resources and capabilities are sought from the scope of the VRIO model, which looks at the internal resources and capabilities from the scope of value, rarity, imitability, and organization. Interviews with the top tier producers and managers reveal the internal success factors of K-POPs. We conclude that these resources and capabilities are from internally accumulated producing know-how, unique managing (training) system, and outstanding all-round entertainment capabilities of the performers. Conclusions - These results indicate that the core resources and capabilities of K-POP are robust. It will take a significant amount of time and money to imitate for followers, because these resources and capabilities are the result of time investment and are embedded into producers' and performers' know-how. Taking Luo (2000)'s argument, K-POP is in the second stage of the globalization process, which is configuring and allocation resource capabilities to a global scope.

The Relationship Between Internal Auditors' Personality Traits, Internal Audit Effectiveness, and Financial Reporting Quality: Empirical Evidence from Jordan

  • ALBAWWAT, Ibrahim Emair;AL-HAJAIA, Mohammad Eid;AL FRIJAT, Yaser Saleh
    • The Journal of Asian Finance, Economics and Business
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    • 제8권4호
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    • pp.797-808
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    • 2021
  • This study examines the interaction between internal auditors' personality traits and the internal audit function effectiveness. It also investigates the effect of such interacted variables on financial reporting quality. This study employed a questionnaire survey to collect data from 193 internal auditors of Jordanian companies listed on the Amman Stock Exchange. The study model is validated and tested using the partial least squares structural equation modelling. The results reveal that all the examined personality traits of internal auditors significantly impact internal audit function effectiveness except for the extraversion trait. The results also show that personality traits have indirect effects on financial reporting quality via internal audit function effectiveness. These results suggest that internal auditors with high scores on openness to experience, emotional stability, and conscientiousness traits can be among the most significant contributors to the internal audit function effectiveness. The results also suggest that internal auditors' personality traits can be regarded as an internal audit function intangible resource that enhances effectiveness. The study's findings might be of interest to many different parties interested in enhancing internal audit function effectiveness and boosting the financial reporting quality, such as external and internal auditors, auditees, human resource departments, and Chief Internal Audit Executives.

선형 동적 시스템 기반의 감정 엔진 모델 (Emotional Engine Model based on Linear Dynamic Systems)

  • 안호석;최진영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.213-215
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    • 2007
  • This paper introduces an emotional behavior decision model for intelligent service robots. An emotional model should make different behavior decisions according to the purpose of the robots. We propose an emotional behavior decision model which can change the character of emotional model and make different behavior decisions although the situation and environment remain the same. We defined each emotional element such as reactive dynamics, internal dynamics, emotional dynamics, and behavior dynamics by state dynamic equations. The proposed system model is a linear system. If you want to add one external stimulus or behavior, you need to add just one dimensional vector to the matrix of external stimulus or behavior dynamics. The case of removing is same. The change of reactive dynamics, internal dynamics, emotional dynamics, and behavior dynamics also follows the same procedure. We implemented the proposed emotional behavior decision model and verified its performance.

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후박마황탕(厚朴麻黃湯)이 ovalbumin으로 유도된 천식 모델 생쥐에 미치는 영향 (Effects of Hubakmawhang-tang on Asthma Model Mice Induced by Ovalbumin)

  • 나가영;이혜인;김영광;문영호
    • 대한한방내과학회지
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    • 제39권4호
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    • pp.451-462
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    • 2018
  • Hubakmawhang-tang (HMT), listed in Geumgweyoryak, is an oriental medicine used for the symptoms of asthma, such as cough and dyspnea. In this study, we investigated the HMT effects on ovalbumin-induced asthmatic in mice. We examined weight changes, airway hyperresponsiveness, histopathological abnormalities, immune cell infiltrations, immunoglobulin and inflammatory cytokine levels, and spleen body weight ratios in asthmatic mice. HMT inhibited airway hyperresponsiveness, immune cell infiltration, and airway remodeling and caused a significant lowering of serum IgE and IgG1 levels. The asthmatic mice had elevated IL-4 levels in lung tissue and this elevation was effectively prevented by HMT. HMT did not cause changes in body weight or in the spleen body weight ratio. Therefore, HMT might have an anti-asthmatic effect in the ovalbumin-induced mouse model.