• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1976.06a
• /
• pp.87.4-88
• /
• 1976

The statistcal study was done on 81 cases of the foreign bodies in the food passages (73 cases) and air passages (8 cases), who had visited the Dept. of Otolaryngology of Kyung Hee Medical Center and treated endoscopically, from Nov. 1971 to Mar 1976. The results were as follows, 1) The incidence of esophageal foreign bodies (73 cases) in order of frequency was coin (61 cases; 83.6%), bone (6 cases; 8.2%), food particles (3 cases; 4.1%), discs (2 cases), and other metals (l case). The incidence of foreign bodies in the air passages (8 cases) was food particles (3 cases; 37.5%), pointed metal (2 cases; 25%), plastic pencil cap (l case), plastic ring (1 case), and wood piece (1 case) in order. 2) In sex distribution, 51 cases (62.9%) were males and 30 cases (37.1%) were females, and the ratio between males and females was about 1.7 : 1.3. In the age incidence, 69 cases (82.5%) of all foreign bodies were under 5 years of age, and especially, coin cases were 59 cases (96.7%) and the highest was 8 years of age, lowest was 11 months of age. 7 cases (87.5%) of all airway foreign bodies were under 10 years of age. 4) The ratio between the food passages(73 cases) and the air passages (8 cases) was about 9 : 1. In the location of the foreign bodies of the food passages, 66 cases (90.4%) were in the first esophageal narrowing, 5 cases (6.9%) in the second narrowing, and 2 cases (2.7%) in the third narrowing. In the air passages, the frequent sites were trachea (5 cases; 62.5%), larynx (2 cases), and bronchus (1 case) in order. 5) In duration of lodgement, 63 cases (86. 3%) of esophageal foreign bodies were removed within 24 hours, and one case was removed within 16 days. The number of cases lodged within 24 hours were 4 cases (50%). in the air passages and one case was removed within 18 days. 6) In treatment, 37 cases (50.7%) of esophageal foreign bodies were extracted by modified upper esophagoscopy, 33 cases (42.5%) by esophagoscopy under the local anesthesia, 3 cases (4.1%) by esophagoscopy under the general anesthesia. 8 cases of the coin cases were passed into the stomach during the endoscopic examination. Laryngeal foreign bodies (2 cases; 25%) were extracted by laryngoscopy under the local anesthesia. 2 cases (40%) of tracheal foreign bodies by Bronchoscopy with tracheotomy under the local anesthesia, 3 cases (60%) by Bronchoscopy under the general anesthesia, and bronchial foreign body (1 case) by open thoracotomy under the general anesthesia, at the Dept. of Chest surgery.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.23 no.4
• /
• pp.233-252
• /
• 2021

This paper is a study to improve the efficiency of mixing technology in the shield TBM chamber. Currently, the number of construction cases using the TBM method is increasing in Korea. According to the increasing use of TBM method, research on TBM method such as Disc Cutter, Cutter bit, and Segment also shows an increasing trend. However, there is little research on the mixing efficiency in chamber and chamber. In order to improve the smooth soil treatment and the behavior of the excavated soil, a study was conducted on the change of the mixing efficiency according to the effective mixing bar arrangement in the chamber. In the scale model experiment, the ground was composed using plastic materials of different colors for ease of identification. In addition, the mixing bar arrangement was different and classified into 4 cases, and the particle size distribution was classified into single particle size and multiple particle size, and the experiment was conducted with a total of 8 cases. The rotation speed of the cutter head of all cases was the same as 5 RPM, and the experiment time was also carried out in the same condition, 1 minute and 30 seconds. In order to check the mixing efficiency, samples at the upper, middle (left or right), and lower positions of each case were collected and analyzed. As a result of the scaled-down model experiment, the mixing efficiency of Case 4 and Case 4-1 increased compared to Case 1 and Case 1-1, which are actually used. Accordingly, it is expected that the mixing efficiency can be increased by changing the arrangement of the mixing bar in the chamber, and it is considered to be effective in saving air as the mixing efficiency increases. Therefore, this study is considered to be an important indicator for the use of shield TBM in Korea.