• Journal of Korean Foot and Ankle Society
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• v.13 no.1
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• pp.28-33
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• 2009

Purpose: This retrospective study was designed to evaluate the treatment results of chronic Achilles tendon rupture by Lindholm method. Materials and Methods: Between 2002 and 2006, we performed the reconstruction of the Achilles tendon by using of the gatrocnemius-sloeus fascia known as Lindholm method. Ten cases of ten patients were enrolled in this study (8 men and 2 women). The mean age of the patients at the time of operation was 49 years (range, 32${\sim}$66 years). The mean follow-up duration was 15.2 months (range, 12${\sim}$19 months). The retrospective review of the clinical history, physical examination, the American Orthopedic Foot and Ankle Society (AOFAS) score were conducted. Results: The mean AOFAS score before surgery was 74.10${\pm}$2.56 and that of the latest follow-up was 90.60${\pm}$5.72. The excellent results were six and good results were four patients. Eight patients were normal triceps power and the others were good. The average of heel to floor distance was 4.5 mm less in the operated legs than the contralateral ones in each patient, but there was no significant difference (p>0.05). The average of calf muscle circumference in the mid-leg was 7.5 mm less in the operated legs than the contralateral ones and there was significant difference (p<0.05). The active range of motion of the ankles, mean plantarflexion was 40 degrees and dorsiflexion was 16.8 degrees in operated side. The contralateral side was 43 degrees in plantarflexion and 19 degrees in dorsiflexion. No case showed rerupture of the reconstructed Achilles tendon. One patient had the superficial wound infection which was treated successfully by antibiotic therapy. Conclusion: It was suggested that the overall results of Lindholm method for the chronic Achilles tendon rupture indicated satisfactory outcomes.

• Journal of Trauma and Injury
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• v.25 no.4
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• pp.217-222
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• 2012

Purpose: Diaphragmatic rupture following trauma is often an associated and missed injury. This report is about our experience with treating traumatic diaphragmatic rupture (TDR). Methods: From January 2007 to September 2012, 18 patients who had a diaphragmatic rupture due to blunt trauma or penetrating injury underwent an operation for diaphragmatic rupture at our hospital. We retrospectively reviewed their medical records, including demographic factors, initial vital signs, associated injuries, interval between trauma and diagnosis, injured side of the diaphragm, diagnostic tools, surgical method or approaches, operative time, herniated organs, complications, and mortality. Results: The average age of the patients was 43 years, and 16 patients were male. Causes of trauma included motor vehicle crashes (n=7), falls (n=7), and stab wounds (n=5). The TDR was right-sided in 6 patients and left-sided in 12. The diagnosis was made by using a chest X-ray (n=3), and thorax or upper abdominal computed tomography (n=15). Ten(10) patients were diagnosed within 12 hours. A thoracotomy was performed in 8 patients, a video-assisted thoracoscopic surgery in 4 patients, a laparotomy in 3 patients, and a sternotomy in one patient. Herniated organs were the omentum (n=11), stomach (n=8), spleen and colon (n=6), and liver (n=6). Eighteen diaphragmatic injuries were repaired primarily. Seven patients underwent ventilator care, and two of them had pneumonia and acute respiratory distress syndrome. There were no operative mortalities. Conclusion: Early diagnosis and surgical treatment determine the successful management of TDR with or without the herniation of abdominal organs. The surgical approach to TDR is chosen based on accompanying organ injuries and the injured side.

• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.474-483
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• 2021

To establish the exclusive role of hydrogen on burst behaviour of Zircaloy-4 during loss-of-coolant accident transients, an extensive single-rod burst tests were conducted on both unirradiated as-received and hydrogenated Zircaloy-4 cladding tubes at different heating rates and internal overpressures. The visual observations of cladding tubes during bursting as well as post-burst are presented in detail to understand the effect of hydrogen concentration, heating rate, and internal pressure. Impact of hydrogen on burst parameters-burst stress, burst strain, burst temperature-during loss-of-coolant accident transients are compared and discussed. Rupture at multiple locations for hydrogenated cladding at lower internal pressure and higher heating rate is reported for the very first time. A novel burst criterion accounting hydrogen concentration in nuclear fuel cladding is proposed.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1307-1313
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• 2019

Recent analysis results with realistic assumptions provide the variability of operator allowable time for the initiation of aggressive cooldown under small break loss of coolant accident or steam generator tube rupture with total failure of high pressure safety injection. We investigated how plant risk may vary depending on the variability of operators' failure probability of timely initiation of aggressive cooldown. Using a probabilistic safety assessment model of a nuclear power plant, we showed that plant risks had a linear relation with the failure probability of aggressive cooldown and could be reduced by up to 10% as aggressive cooldown is more reliably performed. For individual accident management, we found that core damage potential could be gradually reduced by up to 40.49% and 63.84% after a small break loss of coolant accident or a steam generator tube rupture, respectively. Based on the importance of timely initiation of aggressive cooldown by main control room operators within the success criteria, implications for improvement of emergency operating procedures are discussed. We recommend conducting further detailed analyses of aggressive cooldown, commensurate with its importance in reducing risks in nuclear power plants.

• Journal of Chest Surgery
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• v.25 no.3
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• pp.335-340
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• 1992

Truamatic aortic rupture is usually fatal if left untreated. Prompt diagnosis is the cornerstone of suscessful management. But the usual screening tests are non specific and the accuracy of computerized tomography is low, Aortography which is a time consuming procedure may result in false-positive interpretations and significant morbidity. Recently transesophageal echocardiography provides a rapid, effective and relatively safe means of evaluating the distal aortic arch and also affords the opportunity to evaluate the heart during the same study, which may be of benefit in cases of suspected cardiac injury. The experience with the traumatic aortic ruptured patient and a critical review of the literature suggests that transesophageal echocardiography is a useful technique for the diagnosis of ruptured aorta following blunt chest trauma.

• Journal of the Korean institute of surface engineering
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• v.24 no.1
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• pp.8-8
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• 1991

To investigate the effects of substrate on transverse-rupture strength(TRS) and bonding strength between substrate and TiC layer coated by CVD, two kinds of substrate (substrate A:WC-9.5wt%Co-MC*[low C], substrate B: WC-6wt% Co-MC*[high C] were studied in terms of Cobalt and C contents respectively. For preparation of test samples the coating parameters of deposition time, deposition temperature and deposition pressure were varied. The result show that the carbon contents in substrates have greater effects on the TRS of the CVD TiC coated cemented carbide than Co contents in substrates.

• Journal of the Korean institute of surface engineering
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• v.25 no.1
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• pp.8-15
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• 1992

To investigate the effects of substrate on transverse-rupture strength(TRS) and bonding strength between substrate and TiC layer coated by CVD, two kinds of substrate (substrate A: WC-9.5wt% Co-MC＊[low C], substrate B: WC -6wt% Co-MC＊[high C]) were studied in terms of Cobalt and C contents respectively. For preparation of test samples the coating parameters of deposition time, deposition temperature and deposition pressure were varied. The results show that the carbon contents in substrates have greater effects on the TRS of the CVD TiC coated cemented carbide than Co contents in substrates. ＊MC:TiC+TaC

• Journal of the Korean Professional Engineers Association
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• v.25 no.4
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• pp.102-108
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• 1992

This study was carried to find out the soil characteristics of landslide site and to develope landslide prediction method by seismic refraction prospecting. For these aims, landslide condition and travel time were investigated at 68 Landslide sites over the country during 1990 to 1991. The results were as follows. 1. The surface of rupture was included mainly in C layer. Its Hardness was less than 3kg / $\textrm{cm}^2$ at the upper pare of landslide. 2. When the profile line length was 20m, the range of travel time was 40 to 90 msec. The travel time did not differ between bedrocks. 3. Refraction distance ranged from 1 to 7m and mean of that was 2.5m. Travel time was increased according to receiving distance without large variance in the refraction distance but that was appeared large variance out of the refraction distance on slope that has shallow soil depth and discontinuous ground surface. Therefore, the spread distance must be shorten to 10-l5m. 4. The seismic velocity at the first layer(layer of rupture) was less than 500m1sec by degree of weathering and the velocity at the second layer decreased in order of Granite> Granitic gneiss >Sedimentary rock. 5. The first layer observed by seismic refraction was contained C layer that has parent material and weathered rocks of hardness 10-20kg/$\textrm{cm}^2$. 6. Among the range of seismic velocity was less than 200m/sec in 63% of the total plots, 200-300m/sec in 34% and 300-500m /sec in 3%. 7. There was a proportional relationship between seismic prospecting soil depth and executive soil depth, and seismic propection soil depth was about 10 to 20cm deeper than the order.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.1
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• pp.71-78
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• 1992

Zr-4 used for a cladding and an end plug of reactor component has creep deformation under operation at high temperature. Creep is regarded as the time dependent deformation of a material under constant applied stress. Although the major source of the deformation of zirconium component in water-cooled reactors is irradiation creep, the thermal creep may give a rise to significant deformation in reactor component especially at relatively high temperatures and at various constant stresses, and therefore it must be predicted accurately. Stress relaxation is the time dependent change of stress at constant strain and it is a process related intimately to creep. In this paper, the creep behavior and stress relaxation of Zr-4 is examined at the temperature of 50$0^{\circ}C$ that is 40% of the absolute melting temperature of Zr-4 under the stress below yield stress and under the various constant strains. The results obtained are summarized as follows: 1) With an increase of stress, the steady state creep rate increases and the creep rupture time decreases. 2) The steady state creep rate $\varepsilon$(%/s) for the stress $\sigma$sub(c) (kgf/mm super(2)) of Zr-4 increases outstandingly. All the empirical equations computed for Zr-4 increases outstandingly. All the empirical equations computed for Zr-4 are in accord with Norton's model equation($\varepsilon$=K$\sigma$ sub(c) super (n)). The constants of materials computed are as follows: K=3.9881$\times$10 super(-5), n=1.9608 3) The rupture time T sub(r) (hr) decreases linearly with the increase of stress on the log-log scaled graph. The empirical equations computed for Zr-4 are in accord with Bailey's model equation (T sub(r)=K sub(1)$\sigma$sub(c) super(m)). The constants of materials computed are as follows: K sub(1)=1.2875$\times$10 super(16), m=-3.467 4) It seems clear that the strain could be quantitatively dependent on the high temperature creep properties such as creep stress, rupture time, steady state creep rate and total creep rate. It is found that these relationships are linear on the log-log graph. 5) In stress relaxation test, as the critical constant strain that can be allowed to the specimen is larger, stress relaxation becomes more rapid, and as the constant strain is smaller, the stress relaxation becomes slower.

• Journal of Korean Foot and Ankle Society
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• v.2 no.2
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• pp.93-96
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• 1998

A tibialis posterior and flexor digitorum longus tendon rupture associated with a closed bimalleolar ankle fracture occured in a 30 years old man due to traffic accident. The tendon injury was not recognized before surgery but was diagnosed at the time of operation. The treatment was open reduction and internal fixation of the ankle fracture with primary repair of the ruptured tendons. one year postoperatively, he had a nearly full range of ankle and toes motion without pain and a radiologic normal longitudinal arch. This associated tendon injury, although rare, maybe first time in reviewed similar reports, should be considered in the management of ankle fracture because the tendon rupture could easily have been overlooked.