• 제목/요약/키워드: flutter

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The Effects of Positivity and Negativity of Present and Future on Temporal distance judgment and Time expression (현재와 미래의 긍정성과 부정성이 시간적 거리 판단과 시간표현에 미치는 영향)

  • Lee, GoEun;Shin, HyunJung
    • Korean Journal of Cognitive Science
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    • 제29권4호
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    • pp.265-281
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    • 2018
  • This study examines the effect of present and future situation on the temporal distance estimation to the future. The effect of present and future situation on time expression was verified. In Experiment 1, an experiment was conducted to investigated the effects of positivity/negativity situation of the present and the future on the judgment of subjective the distance to a certain future time. The results are as follows. When the present is positive and the future is negative, the future looks closer than the objective temporal distance and comes faster, When the present is negative and the future is positive, the future looks farther and comes slower. On the other hand, when the present and the future are both negative, the future looks coming slower. And when the present and the future are both positive, the future is expected to come faster. In Experiment 2, the cognitive and emotional aspects of subjective time through time expressions. It can be said to be 'the time of perseverance' in the sense of time for effort. On the other hand, when the present is positive compared to the future, the time seems go fast and we generally prefer to use cognitive expressions such as 'fast' and emotional expressions such as 'near' and 'pleasant' and 'flutter'. It is 'the time of availability', which means the time to enjoy and utilize.

Section Model Study on the Aerodynamic Behaviors of the Cable-Stayed Bridges with Two I-Type Girders Considering Structural Damping and Turbulence Intensity (2개의 I형 거더를 가진 사장교의 구조감쇠비 및 난류강도를 고려한 공기역학적 거동에 관한 단면모형실험 연구)

  • Cho, Jae-Young;Kim, Young-Min;Cho, Young-Rae;Lee, Hak-Eun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • 제26권6A호
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    • pp.1013-1022
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    • 2006
  • Although the cable-stayed bridges with two I-type girders inherently do not have good aerodynamic characteristics, a lot of the bridges with this type girders are constructed in Korea recently because of an economical merit. This paper investigated the aerodynamic characteristics of the cable-stayed bridges with two I-type girders. Section model tests were conducted in order to investigate the aerodynamic behaviors of this section with varying of the angles of attack, turbulence intensity and damping ratios. Two deck section configurations with different torsional stiffness were studied under construction and after completion respectively. Three types of the fairings were investigated to improve the aerodynamic characteristics of the bridges. The result of this study showed that the traditional section model test in uniform flow estimates the aerodynamic behavior rather pessimistically. The wind induced responses of the bridges were severely varied in accordance with the turbulence intensity and the structural damping ratio. The proposed fairing reduced the magnitude of the vortex-shedding vibrations and buffeting responses. It also increased the wind speed at which flutter occurs. It is expected that these investigations would provide a lot of information for the design of the cable stayed bridges with two I-type girders regarding wind resistance.

Long term prognosis of patients who had a Fontan operation (폰탄 수술을 받은 환아들의 장기적 예후)

  • Kim, Hyun-Jung;Bae, Eun-Jung;Noh, Jung-Il;Choi, Jung-Yun;Yun, Yong-Su;Kim, Wong-Hwan;Lee, Jung-Yeul;Kim, Yong-Jin
    • Clinical and Experimental Pediatrics
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    • 제50권1호
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    • pp.40-46
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    • 2007
  • Purpose : This study assessed the long term survival rate and long term complications of patients who had a modified Fontan operation for functionally univentricular cardiac anomaly. Methods : Between June 1986 and December 2000, 302 patients with a functional single ventricle underwent surgical interventions and were followed up until February 2006. The mean follow-up period was $8.3{\pm}5.3years$ (range 3.5-18 years). Their median age was 2.4 years at the Fontan operation. The survival rate, the incidence and the risk factor of late complications were evaluated retrospectively. Results : The verall survival rate was 91 percent at 5 years and 87 percent at 10 years. In multivariate analysis, early calendar year of operation and significant regurgitation were risk factors of death. The surviving patients showed NYHA functional class I in 82 percent, class II in 15 percent, and class III in 3 percent. Redo Fontan operations were necessary in 8.8 percent of patients at average $12.8{\pm}3.6years$ after initial Fontan operation. The most common cause of Fontan conversion was atrial arrhythmia. The incidence of thromboembolic events was 9.3% and these complications were associated with the occurrence of atrial tachyarrhythmia. Supraventricular tachycardia including atrial flutter or fibrillation were reported on the follow-up examination by 11.2 percent of survivors after $8.4{\pm}5.6years$. Atriopulmonary connection showed higher rates of late tachycardia than lateral tunnel operation. Conclusions : This study revealed that the recent survival rate of Fontan type operation was satisfactory, but the occurrence of late complications after a Fontan type operation increased with the longer survival. There is a need for strict follow up and early treatment of late complications in patients who had a Fontan operation.

Results of radiofrequency catheter ablation in children and adolescent with tachyarrhythmia (소아 청소년 부정맥 환자에서 고주파 전극도자 절제술의 이용 성적)

  • Chang, Young Beom;Lee, Seung Hyun;Kang, Eun Young;Rhee, Kyoung-Suk;Joo, Chan Uhng
    • Clinical and Experimental Pediatrics
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    • 제50권11호
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    • pp.1085-1090
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    • 2007
  • Purpose : Radiofrequency catheter ablation (RFCA) has become an effective therapeutic modality for treating pediatric tachyarrhythmias. Using conventional RFCA catheters, ablation of parahisian accessory pathways may be difficult and have high risk for heart block. We reviewed the efficacy and complications of the RFCA in children and adolescent with arrhythmias including parahisian accessory pathways. Methods : We studied 48 patients (aged 2 years to 20 years) who had undergone RFCA from August 2003 to March 2007. We reviewed clinical findings, electrophysiologic studies, RFCA data, complications, and follow-up results of the patients. Results : Mean age of the patients was 13.1 years. Numbers and types of arrhythmias (age, acute success rate) were as follows: 19 WPW syndrome including 5 parahisian accessory pathways ($13.7{\pm}4.6yr$, 18/19), 11 atrioventricular reentrant tachycardia with concealed bypass tract ($12.3{\pm}5.0yr$, 10/11), 13 atrioventricular nodal reentrant tachycardia ($12.6{\pm}4.4yr$, 13/13), 4 atrial flutter ($13.0{\pm}7.4yr$, 3/4), and 1 ventricular tachycardia (20 yr, 1/1). Associated cardiac structural lesion was not detected in 48 patients. The recurrence rate was 6.5%, and the final success rate was 93.8%. Conclusion : These results suggest that RFCA is a highly effective treatment method in children and adolescent with tachyarrhythmia.

Identification of Compound Heterozygous Alleles in a Patient with Autosomal Recessive Limb-Girdle Muscular Dystrophy (상염색체 열성 지대형 근이영양증 환자로부터 TTN 유전자의 복합 이형접합성 대립유전자의 분리)

  • Choi, Hee Ji;Lee, Soo Bin;Kwon, Hye Mi;Choi, Byung-Ok;Chung, Ki Wha
    • Journal of Life Science
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    • 제31권10호
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    • pp.913-921
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    • 2021
  • Limb-girdle muscular dystrophy (LGMD) which is characterized by progressive muscle weakening of the hip and shoulder shows both dominant and recessive inheritances with many pathogenic genes including TTN. This study performed to identify genetic causes of a male patient with late onset (45 years old) autosomal recessive LGMD and atrial flutter. By application of the whole exome sequencing, we identified bi-allelic variants of TTN gene in the patient. One allele had a single missense variant of [c.24124G>T (p.V8042F)], while the other allele consisted of three missense variants of [c.29222G>C (p.R9741P) + c.67490A>G (p.H22497R) + c.75376C>T (p.R25126C)]. The p.V8042F allele was transmitted from his mother, while the other haplotype allele was putatively transmitted from his father. His two unaffected sons had only the p.R9741P. These variants have been not reported or rarely reported in the public human genome databases (1,000 Genome, gnomAD, and KRGDB). Most variants were located in the highly conserved immunoglobulin or fibronectin domains and were predicted to be pathogenic by the in silico analyses. The TTN giant protein plays a key role in muscle assembly, force transmission at the Z-line, and maintenance of resting tension in the I-band. In conclusion, we think that these bi-allelic compound heterozygous mutations may play a role as the genetic causes of the LGMD phenotype.