• Title/Summary/Keyword: Multiple Shock

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Proton Acceleration in Weak Quasi-parallel Intracluster Shocks: Injection and Early Acceleration

  • Kang, Hyesung;Ryu, Dongsu;Ha, Ji-Hoon
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.42.1-42.1
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    • 2018
  • Collisionless shocks with low sonic Mach numbers, M<4, are expected to accelerate cosmic ray (CR) protons via diffusive shock acceleration (DSA) in the intracluster medium (ICM). However, observational evidence for CR protons in the ICM has yet to be established. Performing particle-in-cell simulations, we study the injection of protons into DSA and the early development of a nonthermal particle population in weak shocks in high ${\beta}$ plasmas. Reflection of incident protons, self-excitation of plasma waves via CR-driven instabilities, and multiple cycles of shock drift acceleration are essential to the early acceleration of CR protons in supercritical quasi-parallel shocks. We find that only in ICM shocks with $M{\geq}2.3$, a sufficient fraction of incoming protons are reflected by the overshoot in the shock electric potential and magnetic mirror at locally perpendicular magnetic fields, leading to efficient excitation of magnetic waves via CR streaming instabilities and the injection into the DSA process. Since a significant fraction of ICM shocks have M < 2.3 CR proton acceleration in the ICM might be less efficient than previously expected. This may explain why the diffuse gamma-ray emission from galaxy clusters due to proton-proton collisions has not been detected so far.

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The Moderating Effect of Emotional Intelligence on the Relationship between Transition Shock and Adaptation on Clinical Practice among Nursing Students (간호대학생의 전환충격과 임상실습적응의 관계에서 감성지능의 조절효과)

  • Lee, Oi Sun;Kim, Eun Jae
    • Journal of Digital Convergence
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    • v.17 no.11
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    • pp.387-394
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    • 2019
  • The purpose of this study was to identify the moderated effects of emotional intelligence on the relationship between transition shock and adaptation on clinical practice among nursing students. Subjects were 185 associate nursing students associate nursing students(3rd). The data were collected using self -report questionnaire from May 1 to June 14, 2019. Data were analyzed by descriptive statistics, t-test, ANOVA, Pearson correlation and hierarchical multiple regression with SPSS/WIN 23.0. Mean point of transition shock(4 point scale) was 2.32. Mean point of emotional intelligence(5 point scale) was 3.61, and adaptation on clinical practice(5 point scale) was 3.40. Transition shock were significantly negative correlation with emotional intelligence(r=-.26. p <.001) and adaptation on clinical practice(r=-.43. p <.001) in nursing students. Emotional intelligence were significantly positive correlation with adaptation on clinical practice(r=.36. p <.001). Emotional intelligence has been shown to modulate the relationship between transition shock shock and adaptation on clinical practice(${\Delta}R^2=0.21$, p <.001). Therefore, to decrease the transition shock and to increase the adaptation on clinical practice of nursing students, It is necessary to develop the program for increase emotional intelligence of nursing students.

Acute Respiratory Distress Syndrome With Alveolar Hemorrhage due to Strongyloidiasis Hyperinfection in an Older Patient

  • Kim, Eun Jin
    • Annals of Geriatric Medicine and Research
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    • v.22 no.4
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    • pp.200-203
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    • 2018
  • Strongyloides stercoralis is an intestinal nematode that occurs sporadically in temperate areas like Korea. People who are in the immunosuppressed state, over the age of 65 or under the corticosteroid therapy are at risk for developing Strongyloides hyperinfection syndrome. Acute respiratory distress syndrome (ARDS) with alveolar hemorrhage is a rare presentation of Strongyloides hyperinfection. A 78-year-old man had been irregularly injected corticosteroid on his knees, but did not have any immunosuppressive disease. He was initially diagnosed with ARDS and septic shock. Bronchoalveolar lavage (BAL) fluid was bloody and its cytology revealed helminthic larvae identified as S. stercoralis. Results of Cytomegalovirus polymerase chain reaction (PCR), Pneumocystis jirovecii PCR, and Aspergillus antigen testing of the BAL fluid were positive. The clinical progress quickly deteriorated with multiple organ failure, shock and arrhythmia, so he finally died. This is a rare case of ARDS in an older patient without any known immunosuppressive conditions, with alveolar hemorrhage and S. stercoralis being found via BAL.

Analysis of impact damage behavior of GFRP-strengthened RC wall structures subjected to multiple explosive loadings (복합 폭발하중을 받는 GFRP 보강 RC 벽체 구조물의 비선형 충격 손상거동 해석)

  • Noh, Myung-Hyun;Lee, Sang-Youl;Park, Tae-Hyo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.1033-1036
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    • 2008
  • In this paper, the analysis of impact damage behavior of a reinforced concrete structure that undergoes both a shock impulsive loading and an impact loading due to the air blast induced from an explosion is performed. Firstly, a pair of multiple loadings are selected from the scenario that an imaginary explosion accident is assumed. The RC structures strengthened with glass fiber reinforced polymer (GFRP) composites are considered as a scheme for retrofitting RC wall structures subjected to multiple explosive loadings and then the evaluation of the resistant performance against them is presented in comparison with the result of the evaluation of a RC structure without a retrofit. Also, in order to derive the result of the analysis similar to that of real explosion experiments, which require the vast investment and expense for facilities, the constitutive equation and the equation of state (EOS) which can describe the real impact and shock phenomena accurately are included with them. In addition, the numerical simulations of two concrete structures are achieved using AUTODYN-3D, an explicit analysis program, in order to prove the retrofit performance of a GFRP-strengthened RC wall structure.

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The Comparison of Base Deficit, Lactate, and Strong Ion Gap as Early Predictor of Mortality in Trauma Patients (외상환자의 초기 사망 예측 지표로서의 내원 초기의 염기 결핍, 젖산 및 강이온 차이의 유용성 비교)

  • Park, Kyung Hye;Lee, Kang Hyun;Kim, Seon Hyu;Oh, Sung Bum;Moon, Joong Bum;Kim, Hyun;Hwang, Sung Oh;Kim, Heon Ju
    • Journal of Trauma and Injury
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    • v.18 no.2
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    • pp.127-134
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    • 2005
  • Purpose: Currently, there is a variety of systems available for predicting prognosis of trauma patients such as trauma score, Injury severity score (ISS) and acid-base variables. But it is not clear that the initial acid-base variables are predictors of prognosis in trauma patients at the emergency department. The objective of this study is to compare the base deficit, lactate and strong ion gap as an early predictor of mortality in trauma patients. Methods: Retrospective record review of 136 trauma patients needed to admit to intensive care unit via emergency department (June 2004 to February 2005). Data included age, injury mechanism, ISS, Revised trauma score (RTS), Multiple organ dysfunction score (MODS), Acute physiology and chronic health evaluation III (APACHE III), Glasgow coma scale (GCS), laboratory profiles, calculated anion gap and strong ion gap. Patients were divided into survivors and non-survivors, shock group and non-shock group with comparison by t-test;significance was assumed for p<0.05. Correlation between acid-base variables and mean arterial blood pressure (MABP) was evaluated. Results: There was a significant difference between the RTS (p=0.00), APACHE III (p=0.00), MODS (p=0.00), GCS (p=0.00) of survivors and non-survivors. There was no significant difference between the ISS (p=0.082), lactate (p=0.541), base excess (p=0.468) and SIG (p=0.894) of survivors and non-survivors. There was a significant difference between the RTS (p=0.023), APACHE III (p=0.002), lactate (p=0.000), base excess (p=0.000) and SIG (p=0.000) of shock and non-shock group. There was no significant difference between the ISS (p=0.270), MODS (p=0.442) and GCS (p=0.432) of shock and non-shock group. The base excess was most correlated to MABP (r2=0.150). Conclusion: Initial base deficit, serum lactate and SIG are not predictors of mortality in moderate to severe trauma patients. Initial base deficit, serum lactate and SIG are correlated with the mean arterial blood pressure in trauma patients in emergency department.

Intervention Analysis with Application to Oil Shock and WPI of Korea

  • Park, Chi-Kyung;Park, Sung-Joo
    • Journal of the Korean Operations Research and Management Science Society
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    • v.7 no.1
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    • pp.17-29
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    • 1982
  • This paper is concerned with the application of the intervention analysis to the wholesale Trice index of Korea. There were four big shocks on the WPI during the last two decades, which were caused by the series of oil price hikes and changes in the foreign exchange rate. Intervention analysis of these multiple shocks revealed the nature and causalities of each shocks to the general price level of Korea.

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Controlling of detonation strength through inserted gaps in multi-material shock physics simulation (화약내 Gap을 통한 폭발력 제어 가능성에 대한 수치해석적 연구)

  • Lee, Jinwook;Yoh, Jai-ick
    • 한국연소학회:학술대회논문집
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    • 2012.04a
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    • pp.275-278
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    • 2012
  • We investigate the interaction between the propagation of detonation and inserted gaps in the high explosive. The Eulerian-based multi-material simulation code validated through comparison with experimental results was used. A series of gap materials is used to understand the detonation propagation characteristic in the presence of multiple gaps.

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Ultrasound-guided Extracorporeal Shock Wave Therapy Combined with Multiple Needling for Calcific Tendinitis in Shoulder (견관절의 석회화 건염에 대한 초음파 유도하 다발성 천공술 및 고에너지 체외 충격파 병합치료)

  • Jung, Tae Wan;Song, Dong Ik;Lee, Soon Hyuck;Jeoung, Woong Kyo
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.7 no.1
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    • pp.13-19
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    • 2014
  • Purpose: To evaluate the effectiveness of ultrasonography-guided combined multiple needling and high-energy extracorporeal shock wave therapy (ESWT) for calcific tendinitis of the shoulder. Materials and Methods: We included 42 calcific tendinitis patients who underwent ultrasonograpy-guided multiple needling followed by high-energy ESWT who visited the clinic from January 2010 to June 2013. The average follow up period was 45 weeks. Clinical evaluation was done before and after 12 weeks from treatment, in clinical terms using pain visual analogue scale (P-VAS), ASES, UCLA scores reflecting performance and symptom improvement, and in sonographic terms by studying the changes in size of the calcific nodules. Results: A statistically significant improvement was seen in P-VAS, ASES, UCLA scores and decreased calcification size on sonographic evaluation. Conclusion: Ultrasonography-guided combined multiple needling and high-energy ESWT is considered as a useful method which could provide clinical function improvement and reduction of calcification deposit.

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A CONCEPTUAL DESIGN OF NEW AUTOMATIC BICYCLE TRANSMISSION BY TRIZ AND DESIGN AXIOM

  • Lee, Kun-Sang;Choi, Jun-Ho
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1022-1027
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    • 2008
  • This paper represents a study on the conceptual design of new automatic bicycle transmission. The gear change in a commercial bicycle is carried out by moving the chain between sprockets. By the use of a multiple sprocket for speed change the power loss and transmission shock may occur. To solve the problem of bicycle transmission, the improved solution was derived by the technical contradiction matrix of TRIZ. The conceptual solution is one sprocket which replaces the function of multiple sprockets and adapts actively to the pitch of chain. And it was confirmed to be an adequate design through the Independence Axiom of design axiom.

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Measuring the Economic Impact of the Energy Price Changes in Korea (에너지가격변화의 경제적 효과에 관한 연구)

  • Kim, Suduk;Sonn, Yang-Hoon
    • Environmental and Resource Economics Review
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    • v.10 no.4
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    • pp.495-513
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    • 2001
  • We investigate a practical method of calculating the impact of multiple domestic energy price change on the final demand, production, the export and import change, the change in the balance of payment of Korean economy. By combining an existing computable general equilibrium (CGE) model with the traditional input-output analysis with two additional assumptions on the price behavior, we provide a cost-effective method of analyzing the impact of multiple energy price changes on the domestic economy. The energy price shock we used in this paper is 0.127% increase weighted by the sectoral productions. The total impacts on price level and GDP are 1.258% and -0.940%, respectively. The impact on the total output (GDP and intermediate goods) is about -1.580%.

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