In this paper, a new method of time reversal for defect diagnosis of concealed structure has been proposed based on the detecting technique of structure acoustic wave and the theory of time reversal. The time reversal...In this paper, a new method of time reversal for defect diagnosis of concealed structure has been proposed based on the detecting technique of structure acoustic wave and the theory of time reversal. The time reversal recurrence formula for detecting the acoustic wave speed constitution of concealed structures with bilevel asynchronous test has been established. The wave speed constitution can be reconstructed in 2 D graticule form by means of this method. The result of model test shows the method is valid.展开更多
The selection and result of operative procedure for repairing atrioventricular septal defect (AVSD) are largely dependent on completeness and accuracy of preoperative morphological diagnosis. To evaluate the value of ...The selection and result of operative procedure for repairing atrioventricular septal defect (AVSD) are largely dependent on completeness and accuracy of preoperative morphological diagnosis. To evaluate the value of two dimensional echocardiographic (2DE) technique devised specifically for morpholagical diagnosis, the results of 2DE,angiocardiography and surgery were examined retrospectively in 87 children with AVSD.Age ranged from 3 months to 11 years old (mean 3.9 years). 46 had partial AVSD, 12 had transitional AVSD, 29 had complete AVSD (type A in 21, type B in 4, type C in 4).2DE diagnosis is concordant with surgical diagnosis in 36/37 (97%) patients with partial AVSD, in 25/31 (84%) patients with transitional or complete AVSD. Most discordant diagnosis between 2DE and surgery occurred in patients with transitional or type A AVSD.The 2DE technique for morphological diagnosis of A VSD is superior to angiocardiography.The results indicated that morphological manifestations of AVSD could be clearly demonstrated with the use of apical and subxiphoid 2D imaging planes, reliable morphological diagnosis could be obtained.展开更多
Bridge structure safety monitoring and assessment has been a great concern for the government and the public,and bridge structure safety monitoring and assessment technology has also developed rapidly over the years.I...Bridge structure safety monitoring and assessment has been a great concern for the government and the public,and bridge structure safety monitoring and assessment technology has also developed rapidly over the years.Its goal is to equip relevant organizations and professionals with a deep understanding of the principles and practical applications of these technologies.By doing so,it seeks to facilitate the effective implementation of safety monitoring and assessment practices in bridge management.Ultimately,the aim is to foster the constructive development of road and bridge construction and operational management at a broader level.展开更多
Background Incomplete right bundle branch block （ICRBBB） is commonly associated with atrial septal defect （ASD）, but lacks sufficient diagnostic test characteristics. An abnormal T wave is also often observed in A...Background Incomplete right bundle branch block （ICRBBB） is commonly associated with atrial septal defect （ASD）, but lacks sufficient diagnostic test characteristics. An abnormal T wave is also often observed in ASD, with horizontal or inverted displacement of the proximal T wave limb in the right precordial leads, termed ＂defective T wave＂ （DTW）. Methods We examined the diagnostic test characteristics of combining ICRBBB with DTW as a new index to diagnose ASD. A total of 132 consecutive patients with ASD and 132 cases of age/gender-matched controls without ASD were enrolled. Results Sensitivities of DTW, ICRBBB, and both were 87.1%-87.9%. Specificities were 97.0%, 96.2%, and 100%, respectively. Positive predictive values were 1.3%, 1.1%, and 100.0% respectively, while negative predictive values were 99.9% for each. Conclusion Combining ICRBBB with DTW in electrocardiogram （ECG） as a new index significantly increased the specificity and positive predictive values while maintaining a high sensitivity in diagnosing ASD.展开更多
文摘In this paper, a new method of time reversal for defect diagnosis of concealed structure has been proposed based on the detecting technique of structure acoustic wave and the theory of time reversal. The time reversal recurrence formula for detecting the acoustic wave speed constitution of concealed structures with bilevel asynchronous test has been established. The wave speed constitution can be reconstructed in 2 D graticule form by means of this method. The result of model test shows the method is valid.
文摘The selection and result of operative procedure for repairing atrioventricular septal defect (AVSD) are largely dependent on completeness and accuracy of preoperative morphological diagnosis. To evaluate the value of two dimensional echocardiographic (2DE) technique devised specifically for morpholagical diagnosis, the results of 2DE,angiocardiography and surgery were examined retrospectively in 87 children with AVSD.Age ranged from 3 months to 11 years old (mean 3.9 years). 46 had partial AVSD, 12 had transitional AVSD, 29 had complete AVSD (type A in 21, type B in 4, type C in 4).2DE diagnosis is concordant with surgical diagnosis in 36/37 (97%) patients with partial AVSD, in 25/31 (84%) patients with transitional or complete AVSD. Most discordant diagnosis between 2DE and surgery occurred in patients with transitional or type A AVSD.The 2DE technique for morphological diagnosis of A VSD is superior to angiocardiography.The results indicated that morphological manifestations of AVSD could be clearly demonstrated with the use of apical and subxiphoid 2D imaging planes, reliable morphological diagnosis could be obtained.
文摘Bridge structure safety monitoring and assessment has been a great concern for the government and the public,and bridge structure safety monitoring and assessment technology has also developed rapidly over the years.Its goal is to equip relevant organizations and professionals with a deep understanding of the principles and practical applications of these technologies.By doing so,it seeks to facilitate the effective implementation of safety monitoring and assessment practices in bridge management.Ultimately,the aim is to foster the constructive development of road and bridge construction and operational management at a broader level.
文摘Background Incomplete right bundle branch block （ICRBBB） is commonly associated with atrial septal defect （ASD）, but lacks sufficient diagnostic test characteristics. An abnormal T wave is also often observed in ASD, with horizontal or inverted displacement of the proximal T wave limb in the right precordial leads, termed ＂defective T wave＂ （DTW）. Methods We examined the diagnostic test characteristics of combining ICRBBB with DTW as a new index to diagnose ASD. A total of 132 consecutive patients with ASD and 132 cases of age/gender-matched controls without ASD were enrolled. Results Sensitivities of DTW, ICRBBB, and both were 87.1%-87.9%. Specificities were 97.0%, 96.2%, and 100%, respectively. Positive predictive values were 1.3%, 1.1%, and 100.0% respectively, while negative predictive values were 99.9% for each. Conclusion Combining ICRBBB with DTW in electrocardiogram （ECG） as a new index significantly increased the specificity and positive predictive values while maintaining a high sensitivity in diagnosing ASD.
