• Journal of the Korean GEO-environmental Society
• /
• v.5 no.2
• /
• pp.41-49
• /
• 2004

In this study, a newly modified soil nailing technology named as the SPN (Spiral Pipe Nailing) system, is developed to self drilling method can apply to ground which is hard to keep shape of bore hole. And limit equilibrium analysis with simplified trial wedge method while length ratio and bond ratio being altered was performed to evaluate slope stability considered of tensile strength and bending stiffness. Also, using $FLAC^{2D}$ program, superiority of the SPN system was compared to the GSN (General Soil Nailing) system about an example section. And effects of various factors related to the design of the SPN system, such as the type of drilling method and the bit, are examined throughout a series of the displacement-controlled field pull-out tests. As a result, the SPN system is better than the GSN system in slope stability because of having larger bending stiffness, tensile strength and unit skin friction. And results of simplified trial wedge method are similar to results of TALREN 97 program, commercial limit equilibrium analysis computer software, about an example section. Consequently, it will find out of that the SPN system reduce displacements and settlements in down excavation process as well as to increase the global stability.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2004.03b
• /
• pp.651-658
• /
• 2004

In this study, we introduced the spiral pipe nailing system (refer as SPN system) with self drilling method, can apply to ground which is hard to keep shape of bore hole, and performed limit equilibrium analysis with simplilied trial wedge method while length ratio and bond ratio were altered to evaluate slope stability considered of tensile strength and bending stiffness. A newly soil nailing system named as the SPN system is respected to reduce displacement of nail and increase global slope stability. And effects of various factors related to the design of the SPN system, such as the type of drilling method and the bit, are examined throughout a series of the displacement-controlled field pull-out tests. 6 displacement-controlled field pull-out tests are performed in the present study and the volume of grouting arc also evaluated based on the measurements. In addition, short-term characteristics of pull-out deformations of the newly proposed SPN system are analyzed and compared with those of the general soil nailing system by carrying out the displacement-controlled field pull-out tests.

• Journal of Chest Surgery
• /
• v.41 no.6
• /
• pp.742-746
• /
• 2008

Background: The surgical treatment of pectus carinatum is usually a modified Ravitch operation that consists of complete costal cartilage resection and sternal wedge osteotomy. We tried a simple and easy technique that is resection of only deformed, protruded costal cartilage and pre-sternal compression with using a stainless steel bar and this is done without sternal osteotomy. Therefore, we performed partial cartilage resection and pre-sternal compression with a stainless steel bar and we observed the effects and the efficiency of treatment. Material and Method: From July, 2006 to June, 2008, 10 patients with pectus carinatum underwent our modified technique of pectus carinatum surgery. The effects of surgery and the complications were reviewed. Result: 5 patients with only pectus carinatum underwent our modified technique of pectus carinatum surgery. 5 patients with pectus carinatum and pectus excavatum underwent our modified technique of pectus carinatum surgery and Nuss surgery. The mean patient age was 13.4+3.3 years old. The mean operation time was 137.6+22.9 minutes for the pectus carinatum patients and 234.0+36.5 minutes for the pectus carinatum and pectus excavatum patients. The mean length of hospitalization was 11.8+1.0 days. The Haller pectus index of pectus carinatum was $2.10{\pm}0.21$ preoperatively and this was increased to $2.53{\pm}0.07$ postoperatively. The only complication was simple partial wound disruption in 1 patient. Conclusion: We performed partial cartilage resection and pre-sternal compression with a stainless steel bar in 10 patients with pectus carinatum and its effects were good. Our modified technique of pectus carinatum is easy and simple as compared with the Ravitch operation. But removal of the stainless steel bar has not yet been performed for these patients and long-term follow up is needed to accurately evaluate the. effects of this surgery in many surgical cases.

• Journal of Chest Surgery
• /
• v.32 no.5
• /
• pp.422-427
• /
• 1999

Background: Tachycardia induced heart failure model would be the model of choice for the dilated cardiomyopathy. This more closely resembles the clinical syndrome and does not require major surgical trauma, myocardial ischemia and pharmacological or toxic depression of cardiac function. When heart failure is progressive, application of new surgical procedures to the faling heart is highly risky. It has been shown that recovery trajectory from heart failure is a new method in decreasing animal mortality. The purpose is to establish the control datas for recovery trajectory in the canine heart failure model. Material and Method: 21 mongrel dogs were studied at 4 stages(baseline, at the heart failure, 4 and 8 weeks after recovery). Heart failure was induced during 4 weeks of continuous rapid pacing using a pacemaker. Eight weeks of trajectory of recovery period was allowed. Indices of left ventricular function and dimension were measured every 2 weeks and the hemodynamics were measured by use of Swan-Ganz catheterization and thermodilution method every 4 weeks. Values were expressed as mean${\pm}$standard deviation. Result: 4(20%) dogs died due to heart failure. Left ventricular end-diastolic volume at the 4 stages were 40.8${\pm}$7.4, 82.1${\pm}$21.1, 59.9${\pm}$7.7 and 46.5${\pm}$6.5ml. Left ventricular end-systolic volume showed the same trend. Ejection fractions were 50.6${\pm}$4.1, 17.5${\pm}$5.8, 36.3${\pm}$7.3, and 41.5${\pm}$2.4%. Blood pressure and heart rate showed no significant changes. Pressures of central vein, right ventricle, pulmonary artery, and pulmonary capillary wedge showed significant increase during the heart failure period, normalizing at the end of recovery period. Stroke volumes were 21.5${\pm}$8.2, 12.3${\pm}$3.5, 17.9${\pm}$4.6, and 15.5${\pm}$3.4ml. Blood norepinephrine level was 133.3${\pm}$60.0pg/dL at the baseline and 479.4${\pm}$327.3pg/dL at the heart failure stage(p=0.008). Conclusion: Development of tachycardia induced heart failure model is of high priority due to ready availability and reasonable amenability to measurements. Recovery trajectory after cessation of tachycardia showed reduction of cardiac dilatation and heart function. Application of new surgical procedures during the recovery period could decrease animal mortality.