• Title, Summary, Keyword: failure mechanism

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Development of a Hydrograph Triggered by Earth-Dam-Break for Compiling a Flood Hazard Map (홍수위험지도 작성을 위한 댐 붕괴 지점에서의 유량곡선 산정)

  • Lee, Khil-Ha;Kim, Sung-Wook;Yu, Soonyoung;Kim, Sang-Hyun;Cho, Jinwoo;Kim, Jin-Man
    • The Journal of Engineering Geology
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    • v.23 no.4
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    • pp.381-387
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    • 2013
  • In compiling flood hazard maps for the case of dam-failure, a scenario-based numerical modeling approach is commonly used, involving the modeling of important parameters that capture peak discharge, such as breach formation and progress. In this study, an earth-dam-break model is constructed assuming an identical mechanism and hydraulic process for all dam-break processes. A focus of the analysis is estimation of the hydrograph at the outlet as a function of time. The constructed hydrograph then serves as an upper boundary condition in running the flood routing model downstream, although flood routing is not considered here. Validation was performed using the record of the Tangjishan dam-break in China. The results were satisfactory, with a coefficient of determination of 0.974, Nash-Sutcliffe Coefficient of Efficiency (NSC) of 0.94, and Root Mean Square Error (RMSE) of $610m^3/sec$. The proposed model will contribute to assessments of potential flood hazards caused by dam-break.

A Study on Correlation of Melanin & Pigmentation Disorder and Viscera and Bowels(臟腑) (멜라닌 및 색소 이상 질환과 장부(臟腑)와의 연관성 고찰)

  • Jung, Yu-Jin;Ko, Woo-Shin;Yoon, Hwa-Jung
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.29 no.3
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    • pp.27-41
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    • 2016
  • Objectives : The purpose of this research is to understand melanin with both Korean and Western medicine.Methods : We investigated the comprehension of melanin in both western and Korean medicine through literature review and studied relationships between melanin and five viscera(五臟), especially liver(肝), spleen(脾), kidney(腎). We Also studied representative pigmentary disorders(melasma, vitiligo) in western and Korean medicine to figure out how to understand pigmentary disorders in oriental medicine.Results : The results are as follows. 1. Melanin is associate with liver, because free coursing(疎泄) function of liver is the origin of transport melanin to keratinocyte from melanocyte. Also, melanogenesis factors like MITF and CREB are closely associated with liver and pigmentary disorders occur frequently after stress conditions or women. 2. Melanin is absorbed and scattered in keratinocytes by the function of spleen. Pigmentary disorders result from failure of spleen and formation of phlegm-retained fluid(痰飮). 3. Kidney essence(腎精) is the origin of melanin formation. In addition, corticosteroid, the major hormone of melanogenesis is secreted by adrenalin and adrenalin belongs to kidney(腎) in Korean medicine. 4. Melasma is created by disorder of melanin transport and absorbtion, so melasma is associated liver (肝) and spleen(脾). Therefore the treatment for melasma may focus on improvement function of liver and spleen. 5. The destruction of melanocyte or abnormal melanogenesis by disorder of the immune system, metabolic and affective disorders can make vitiligo, so vitiligo is associated with liver and kidney which are major part of melanin formation. Therefore the treatment of vitiligo can focus on improvement function of liver(肝) and kidney(腎).Conclusion : We compared Korean and western medicine to understand melanin. We also interpreted the mechanism of melanin and pigmantary disorders in western medicine and considered the relationship with visceral manifestation theory(臟象論) in traditional Korean medicine. Further studies are needed to apply comprehension of melanin to clinical stage.

Identification of damage states and damge indices of single box tunnel from inelastic seismic analysis (비탄성 지진 해석을 통한 박스 터널의 손상 상태 및 손상 지수 규명)

  • Park, Duhee;Lee, Tae-Hyung;Kim, Hansup;Park, Jeong-Seon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.18 no.2
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    • pp.119-128
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    • 2016
  • In a performance-based design, the structural safety is estimated from pre-defined damage states and corresponding damage indices. Both damage states and damage indices are well defined for above-ground structures, but very limited studies have been performed on underground structures. In this study, we define the damage states and damage indices of a cut-and-cover box tunnel which is one of typical structures used in metro systems, under a seismic excitation from a series of inelastic frame analyses. Three damage states are defined in terms of the number of plastic hinges that develop within the structure. The damage index is defined as the ratio of the elastic moment to the yield moment. Through use of the proposed index, the inelastic behavior and failure mechanism of box tunnels can be simulated and predicted through elastic analysis. In addition, the damage indices are linked to free-field shear strains. Because the free-field shear strain can be easily calculated from a 1D site response analysis, the proposed method can be readily used in practice. Further studies are needed to determine the range of shear strains and associated uncertainties for various types of tunnels and site profiles. However, the inter-linked platform of damage state - damage index - shear wave velocity - shear strain provides a novel approach for estimating the inelastic response of tunnels, and can be widely used in practice for seismic designs.

Adaptive Consensus Bound PBFT Algorithm Design for Eliminating Interface Factors of Blockchain Consensus (블록체인 합의 방해요인 제거를 위한 Adaptive Consensus Bound PBFT 알고리즘 설계)

  • Kim, Hyoungdae;Yun, Jusik;Goh, Yunyeong;Chung, Jong-Moon
    • Journal of Internet Computing and Services
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    • v.21 no.1
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    • pp.17-31
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    • 2020
  • With the rapid development of block chain technology, attempts have been made to put the block chain technology into practical use in various fields such as finance and logistics, and also in the public sector where data integrity is very important. Defense Operations In addition, strengthening security and ensuring complete integrity of the command communication network is crucial for operational operation under the network-centered operational environment (NCOE). For this purpose, it is necessary to construct a command communication network applying the block chain network. However, the block chain technology up to now can not solve the security issues such as the 51% attack. In particular, the Practical Byzantine fault tolerance (PBFT) algorithm which is now widely used in blockchain, does not have a penalty factor for nodes that behave maliciously, and there is a problem of failure to make a consensus even if malicious nodes are more than 33% of all nodes. In this paper, we propose a Adaptive Consensus Bound PBFT (ACB-PBFT) algorithm that incorporates a penalty mechanism for anomalous behavior by combining the Trust model to improve the security of the PBFT, which is the main agreement algorithm of the blockchain.

Seismic Characteristic Evaluation on Strip-type Damping Devices with Optimized Shape (최적 형상 스트립형 감쇠장치의 내진 특성 평가)

  • Hwang, Jung-Hyun;Ock, Jong-Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.6
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    • pp.26-37
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    • 2019
  • This paper aims to investigate the seismic characteristics of strip-type damping devices possessing optimized shapes for the moment-resisting mechanism throughout analytical and experimental studies. Predicting equations for initial stiffness and yielding strength were introduced and compared with analytical results obtained from finite element analyses (FEAs) using commercial FEA program ABAQUS. In order for establishing predicting equations, two idealized processes were considered and both predicting equations showed that they could provide enough approximations for seismic applications in building structures. Throughout experimental studies, it was noted that structural uncertainties on mild steels, connection details and structural types linking damping devices with building structures could interrupt predicting structural behavior of the devices. Also, it was observed that shear stress concentrations should be considered if shear yielding type devices are applied into building structures. Nevertheless, it was shown that structural conservatism can be established using the predicting equations and seismic applications of the damping devices can enhance the seismic performance of building structures efficiently in the viewpoint that they have high resistance to low-cycle fatigue failures.

Analysis of Pick-up Mechanism for Automatic Transplanter( I ) (자동 채소 정식기 묘 취출 메커니즘 분석(I))

  • Kang, Tae Gyoung;Kim, Sung Woo;Kim, Young Keun;Lee, Sang Hee;Jun, Hyeon Jong;Choi, Il Soo;Yang, Eun Young;Jang, Kil Soo;Kim, Hyeong Gon
    • Journal of agriculture & life science
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    • v.51 no.1
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    • pp.187-192
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    • 2017
  • In various crops, seedlings are preferred to seeds for faster and more effective growth, so transplanters are used for them. This 2-row transplanter was developed to promote the mechanization of vegetable transplanting work which depends on human power. and it can automatically supply seedling tray and transport picked up seedling to the planting hopper. Also, we judged performance of transplanter with comparing seedling missing plant ration according to two types of pick-up method. Result of experiment, in finger-type picking up of 265 seedlings, missing plant ratio was 13.7% with 17 failures of pick-up and 15 collapse of bed soil. and In fork-type picking up of 200 seedlings, failure of pick-up was not appeared and missing plant ratio was low as 4% with 6 dropped during transfer. Therefore for 2-row automatic transplanter, fork-type pick-up device was found to be compatible.

The politics of shadow education market expansion in Korea: Focused on mobilization capabilities and strategies of suppliers (한국 사교육 정책의 작동 메커니즘에 대한 정치적 분석: 공급자의 동원능력과 시장전략을 중심으로)

  • Hwang, Gyu-Seong
    • 한국사회정책
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    • v.20 no.2
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    • pp.233-260
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    • 2013
  • Despite various policies have been implemented to curb shadow education in Korea, it has continued to grow in recent two decades. This study investigates the expansion mechanism of shadow education focused on mobilization capabilities and market strategies of the suppliers. The success and failure of policy toward shadow education depends on how effectively it could block off the way by which the suppliers as the most important actors in politics of shadow education market mobilize consumers' anxieties. But shadow education policies have failed in two points. First, they have lacked honest intention to stop its proliferation. The Constitutional Court Decision Against Anti-Out-Of-School Classes Legislation of 2000 widened the windows of opportunity for the suppliers, and 5.31 educational reform of 1995 was neutral to their mobilization capabilities, though seemingly designed to control shadow education. This policy orientation, which reflected neoliberal Gesinnungsethik defective of Verantwortungsethik, stimulated shadow education to expand in that suppliers' mobilization capabilities were reinforced or remained intact. Second, shadow education suppliers have succeeded in mobilizing the desire and anxiety of potential consumers. To cope with government's policy including improving the qualities of public education, realignment of college entrance systems, and meeting the shadow education needs, they have developed various market strategies such as management of existing demands, creation of responsive demands, and squeezing out new demands. They have succeeded in nullifying policies by employing or mixing strategies with effect. Policy decisions in the future need to be made with reference to Verantwortungsethik, and be more cautious to socio-political contexts of Korea, to mobilization capabilities and market strategies of the suppliers in particular.

Case study of dramatherapy for a bulmina nervosa patient (폭식증 환자의 연극치료 사례)

  • Lee, Hyowon
    • Journal of Korean Theatre Studies Association
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    • no.52
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    • pp.359-397
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    • 2014
  • This paper describes dramatherapy with a bulmina nervosa patient. She was in her early 20s and has been under the various psychotherapies for cure of deep depression since 2005. We had 24 sessions and 3 persons - the patient, the therapist, and the assist-therapist- participated in dramatherapy. I found there's a big collision between her important roles in the course of initial interview and diagnosis. Those roles are 'a good daughter of mom' and 'an independent adult'. Therefore I defined her bulmina nervosa as 'an symbolic behavior repeats compulsively the failure of separation from her mother.' And I set the general goals, the separation from her mother, the awareness and expression of negative emotions, and the diminuation of overeating and vomiting. To attain these object, we had many different dramatic experiences in dramatherapy. We made a self-portrait, the mask of bulmina nervosa, family sculpture, figure work, the past I and the present I, psychodramatic scene and several stories. In order to objective assessment, I used behavioral observation and 6PSM(6 Pieces Story Making) analysis. First of all the most noticeable change was a rapid decrease in over-eating and vomiting. Before the dramatherapy she had overeaten 30 times per week. At the closure it has fallen off to 1 time per week. Another behavioral changes were shift of outward appearance, not going church, working for living, and having a date with only one. She made 3 stories on 1th session, 13th session, and 23th session. And I comparatively analysed those stories with both qualitative and quantitative method. For qualitative analysis, I classified 5 structures according to the substantial similrarity. On protagonist structure, there's no difference. Three protagonists are dead things. The type of task structure is changed from an escape, a traveling, to metamorphosis. The type of obstruction structure is changed from the protagonist to an outside object. The type of closure structure is changed from an exaggerated happy ending, sad ending to probable happy ending. To quantitify the aspects of transformation, I developed an assesment tool using likert scale. It is composed of 4 sub-categories-reality testing, imagination, ego-strength, optimism problem-solving. In reality testing category, a shift of score was 9-11-15, imagination 2-5-5, ego strength 3-2-2, optimism 6-3-7, and total score 20-21-29. This change of score reflects the growth of problem solving capacity. Viewed in this light, dramatherapy with this girl was successful on the whole. The thing had significant effect on it was psycho-dynamic approach focused on separation from her mother and defence mechanism to avoid negative emotion. And assessment method used in this case will be full of suggestions to researches to come.

Changes of Brain Natriuretic Peptide Levels according to Right Ventricular HemodynaMics after a Pulmonary Resection (폐절제술 후 우심실의 혈역학적 변화에 따른 BNP의 변화)

  • Na, Myung-Hoon;Han, Jong-Hee;Kang, Min-Woong;Yu, Jae-Hyeon;Lim, Seung-Pyung;Lee, Young;Choi, Jae-Sung;Yoon, Seok-Hwa;Choi, Si-Wan
    • The Korean Journal of Thoracic and Cardiovascular Surgery
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    • v.40 no.9
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    • pp.593-599
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    • 2007
  • Background: The correlation between levels of brain natriuretic peptide (BNP) and the effect of pulmonary resection on the right ventricle of the heart is not yet widely known. This study aims to assess the relationship between the change in hemodynamic values of the right ventricle and increased BNP levels as a compensatory mechanism for right heart failure following pulmonary resection and to evaluate the role of the BNP level as an index of right heart failure after pulmonary resection. Material and Method: In 12 non small cell lung cancer patients that had received a lobectomy or pnemonectomy, the level of NT-proBNP was measured using the immunochemical method (Elecsys $1010^{(R)}$, Roche, Germany) which was compared with hemodynamic variables determined through the use of a Swan-Garz catheter prior to and following the surgery. Echocardiography was performed prior to and following the surgery, to measure changes in right ventricular and left ventricular pressures. For statistical analysis, the Wilcoxon rank sum test and linear regression analysis were conducted using SPSSWIN (version, 11.5). Result: The level of postoperative NT-proBNP (pg/mL) significantly increased for 6 hours, then for 1 day, 2 days, 3 days and 7 days after the surgery (p=0.003, 0.002, 0.002, 0.006, 0.004). Of the hemodynamic variables measured using the Swan-Ganz catheter, the mean pulmonary artery pressure after the surgery when compared with the pressure prior to surgery significantly increased at 0 hours, 6 hours, then 1 day, 2 days, and 3 days after the surgery (p=0.002, 0,002, 0.006, 0.007, 0.008). The right ventricular pressure significantly increased at 0 hours, 6 hours, then 1 day, and 3 days after the surgery (p=0.000, 0.009, 0.044, 0.032). The pulmonary vascular resistance index [pulmonary vascular resistance index=(mean pulmonary artery pressure-mean pulmonary capillary wedge pressure)/cardiac output index] significantly increased at 6 hours, then 2 days after the surgery (p=0.008, 0.028). When a regression analysis was conducted for changes in the mean pulmonary artery pressure and NT-proBNP levels after the surgery, significance was evident after 6 hours (r=0.602, p=0.038) and there was no significance thereafter. Echocardiography displayed no significant changes after the surgery. Conclusion: There was a significant correlation between changes in the mean pulmonary artery pressure and the NT-proBNP level 6 hours after a pulmonary resection. Therefore, it can be concluded that changes in NT-proBNP level after a pulmonary resection can serve as an index that reflects early hemodynamic changes in the right ventricle after a pulmonary resection.

Effects of Removal Times of Transplanted Pituitary Gland on Induction of Ovulation and Levels of Estrogen and Progesterone in Immature Rats (미성숙 쥐에 이식한 뇌하수체의 경시별제거가 배란유도와 Estrogen 및 Progesterone수준에 미치는 영향)

  • Lee, J. H.;Kim, Y. H.;Lee, W.
    • Journal of Embryo Transfer
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    • v.2 no.1
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    • pp.36-46
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    • 1987
  • The present work was designed to understand the mechanism of superovuiation and the cause of early embryo loss and Implantation failure in the superovulating immature female rats which were elaborated by a pituitary gland transplantation. A pituitary gland obtained from the orchidectomized rats was transplanted under the right kidney capsule of 28 day old female rats (PGT group) on the starting day of experiment which was designated as Day 2. The grafted pituitary glands were removed at 6h (RPGT 6h group), 12h (RPGT 12hgroup) and 24h (RPGT 24h group) after the transplantation. Control rats were treated with 41U PMSG on Day 2 (PMSG group). The estrous cycle and the levels of plasma progesterone and estradiol-17$\beta$ were observed on Day 0, Day 5, respectively. The implantation sites, the weights of ovary and uterus, and the number of corpora lutea were examined in all group on Day 8. The resuft obtained were summarized as follows: 1. The percentages of the number of the rats in proestrus and estrus were 93.0%, 82.6%, 0%, 90.7% and 89.5% in PMSG, PGT, RPGT6h, RPGT12h and RPGT24h group, respectively. The synchronization of estrus cycle was dchieved in all groups. 2. The mating rates of each group were 80.2, 75.0, 0, 56.4, 57.8% in PMSG, PGT, RPGT6h, RPGT12h, RPGT24h group, respectively. 3. The numbers of copora lutea on Day 8 were 47.1 i 4.9, 18.1 $\pm$0.5, 14.1 i 0.3 and 8.9 $\pm$ 0.3 in PGT, RPGT24h, RPGTl2h and PMSG group, respectively. There were signIficantly difference between all groups (P<0.05). 4. The numbers of implantation sites (18.1 +- 4.0) in PGT group on Day 8 were higher than those of PMSG (8.5 $\pm$ 2.5), RPGT 12h (9.8 i 0.2) and RPGT 24h group (10.8 i 0.2) (P<0.05). 5. The ovarlan weights in PGT (95.2 $\pm$ 14.3mgIlOOg BW), RPGT 12h (51.7 $\pm$ 0.6mgIlOOg BW), and RPGT24h (57.9 $\pm$ 0.9mg/l00g 8W) groups were significantly higher than those of PMSG group (30.4 $\pm$7.4mg/l00g BW) (P<0.05). 6. The uterine weights in PMSG (672.4 $\pm$ 4.7mg/l00g 8W), and PGT (660.7 $\pm$7.8mg/l00g BW) groupswere greater than those of RPGT 12h (403.0 $\pm$ 1.lmg/lOOg BW) and RPGT 24h (490.1 $\pm$ 0.9mg/l00g BW) group (P<0.05). 7. The plasma progesterone levels in PGT groups (15 lng/ml) on Day 5 were higher than those of PMSG (83ng/ml), RPGT 12h (S7ng/ml), RPGT24h (8lng/ml) group (P<0.05). 8. The plasma estradiol-17$\beta$ levels in PMSG group (lBSpg/ml) on Day S were higher than those of RPGT 24h (l3pg/ml) group (P<0.05). But estradiol-17$\beta$ levels in PGT and RPGT 12h group were too low to discuss.

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