• Journal of the Korean Society of Hazard Mitigation
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• v.5 no.4 s.19
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• pp.29-36
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• 2005

In this study, relations among unconfined compressive strength, strain at maximum strength and depth were compared with each other. Test specimen is marine clay originated from the place near Ga-duck island in Busan city. In addition, influence of impure material contained in specimen and that of total core recovery(TCR) on unconfined compressive strength and degree of disturbance were investigated. As a result of tests, unconfined compressive strength decreases as strain corresponding to maximum strength increases. Also, the deeper the sampling depth and the bigger the TCR, the unconfined compressive strength increases. Especially, as the TCR increases, the unconfined compressive strength Increases and quality of specimen is enhanced.

• Journal of Korean Neurosurgical Society
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• v.47 no.1
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• pp.55-57
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• 2010

Ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine is rare, even in the Far East. A 45-year-old female presented with a 4month history of progressive motor weakness in the lower extremities, numbness below the midthoracic area, and spastic gait disturbance. Neuroradiological examinations revealed massive OPLLs at the T4-T6 levels with severe anterior compression of the spinal cord. Anterior decompressive corpectomies with bone grafts were performed from T4 to T6 using a trans-thoracic approach. After surgery, the patient made an uneventful recovery. However, eleven years after surgery, the patient developed recurrent lower extremity weakness and spastic gait disturbance. De novo OPLLs at the C6-T2 levels were responsible for the severe spinal cord compression on this occasion. After second surgery, paralysis in both legs was resolved. We present a rare case of late cervicothoracic OPLL in a patient surgically treated for thoracic OPLL.

• Journal of Korean Neurosurgical Society
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• v.48 no.4
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• pp.335-341
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• 2010

Objective : Anterior cervical corpectomy with fusion (ACF) or laminoplasty may be associated with substantial number of complications for treating multilevel cervical ossification of the posterior longitudinal ligament (OPLL) with significant cord compression. For more safe decompression and stabilization in multilevel cervical OPLL with prominent cord compression, we propose circumferential cervical surgery (selective ACF and laminoplasty) based on our favorable experience. Methods : Twelve patients with cervical myelopathy underwent circumferential cervical surgery and all patients showed multilevel OPLL with Signal change of the spinal cord on magnetic resonance imaging (MRI). A retrospective review of clinical, radiological. and surgical data was conducted. Results : There were 9 men and 3 women with mean age of 56.7 years and a mean follow up period of 15.6 months. The average corpectomy level was 1.16 and laminoplasty level was 4.58. The average Japanese Orthopedic Association score for recovery was 5.1 points and good clinical results were obtained in 11 patients (92%) (p < 0.05). The average space available for the cord improved from 58.2% to 87.9% and the average Cobb's angle changed from 7.63 to 12.27 at 6 months after operation without failure of fusion (p < 0.05). Average operation time was 8.36 hours, with an estimated blood loss of 760 mL and duration of bed rest of 2.0 days. There were no incidences of significant surgical complications, including wound infection. Conclusion : Although the current study examined a small sample with relatively short-term follow-up periods, our study results demonstrate that circumferential cervical surgery is considered favorable for safety and effectiveness in multilevel OPLL with prominent cord compression.

• Membrane and Water Treatment
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• v.6 no.3
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• pp.205-224
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• 2015

A novel hydrophilic poly (vinylidene fluoride)/poly (p-phenylene terephthalamide) (PVDF/PPTA) blend membrane was prepared by in situ polycondensation of p-phenylene diamine (PPD) and terephthaloyl chloride (TPC) in PVDF solution with subsequent nonsolvent induced phase separation (NIPS) process. For comparison, conventional solution blend membrane was prepared directly by adding PVDF powder into PPTA polycondensation solution. Blend membranes were characterized by means of viscometry, X-ray photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FESEM). The effects of different blending methods on membrane performance including water contact angle (WCA), mechanical strength, anti-fouling and anti-compression properties were investigated and compared. Stronger interactions between PVDF and PPTA in in situ blend membranes were verified by viscosity and XPS analysis. The incorporation of PPTA accelerated the demixing rate and caused the formation of a more porous structure in blend membranes. In situ blend membranes exhibited better hydrophilicity and higher tensile strength. The optimal values of WCA and tensile strength were $65^{\circ}$ and 34.1 MPa, which were reduced by 26.1% and increased by 26.3% compared with pure PVDF membrane. Additionally, antifouling properties of in situ blend membranes were greatly improved than pure PVDF membrane with an increasing of flux recovery ratio by 25%. Excellent anti-compression properties were obtained in in situ blend membranes with a stable pore morphology. The correlations among membrane formation mechanism, structure and performance were also discussed.

• The Research Journal of the Costume Culture
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• v.19 no.2
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• pp.334-345
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• 2011

A study on compressive garments guarantee the required pressure and form depending on the type of disease and the state of injury can be used in the preventive treatment of cardiovascular disease. This research is to provide a preliminary data to develop medical clothing products, especially knitted compression garments. Starting from analyzing knitted structure of imported pressure goods to apply to test samples, 11 kinds of knitted stretchy fabrics were manufactured under the various knitting conditions, then their tensile, mechanical and hand properties were measured. In comparison size changes by knitting structure, tuck stitch applied structure showed an increase in course direction and decrease in wale direction. Float stitch applied structure indicated the contraction of size in width because of unformed loops and floated yarn on the technical back of fabric. As a result of tensile properties in tuck and float applied structure, tensile strength was increased in the course direction. On the other hand, the more loops overlapped due to the tuck and float stitch, the more decreased their elongation and elastic recovery were. In case of mechanical properties, as the tuck and float stitch were overlapped double or triple the bending and shearing properties were risen. Accordingly, the drape of fabric becomes stiff, and its surface becomes rough and uneven. The measurements of hand properties showed that the value of KOSHI, FUKURAMI NUMERI in tuck and float applied structure are higher than the plain structure. This results from the relationship between the mechanical and hand properties.

• Journal of Trauma and Injury
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• v.34 no.2
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• pp.130-135
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• 2021

Celiac artery compression is a rare condition in which the celiac artery is compressed by the median arcuate ligament. Case reports of compression after trauma are hard to find. Blunt traumatic pericardium rupture is also a rare condition. We report a single patient who experienced both rare conditions from a single blunt injury. An 18-year-old woman was brought to the trauma center after a fatal motorcycle accident, in which she was a passenger. The driver was found dead. Her vital signs were stable, but she complained of mild abdominal pain, chest wall pain, and severe back pain. There were no definite neurologic deficits. Her initial computed tomography (CT) scan revealed multiple rib fractures, moderate lung contusions with hemothorax, moderate liver injury, and severe lumbar spine fracture and dislocation. She was brought to the angiography room to check for active bleeding in the liver, which was not apparent. However, the guide wire was not able to pass through the celiac trunk. A review of the initial CT revealed kinking of the celiac trunk, which was assumed to be due to altered anatomy of the median arcuate ligament caused by spine fractures. Immediate fixation of the vertebrae was performed. During recovery, her hemothorax remained loculated. Suspecting empyema, thoracotomy was performed at 3 weeks after admission, revealing organized hematoma without pus formation, as well as rupture of the pericardium, which was immediately sutured, and decortication was carried out. Five weeks after admission, she had recovered without complications and was discharged home.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1183-1191
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• 2000

Operating conditions for reduction of membrane fouling in treatment of dissolved organic matter by UF membrane process were investigated by pilot-scale plant using various operating conditions. As inlet pressure increased, increament of transmembrane pressure and flux decline were faster. The reason was due to the increase in adsorption of dissolved organic matter and the development of cake layer compression on the membrane surface. When efficient pressure (the difference of pressure between backwash and transmembrane pressures) was high, small amount of pollutant was retained on the membrane surface. When backwash was frequently conducted, low concentration of pollutant was maintained in recycling water. Therefore, backwash could be efficiently conducted with high efficient pressure and high frequency. Fouling rate was correlated with backwash and inlet pressures, recovery rate and cumulative permeated volume. Among the operating parameters backwash pressure was most closely related to fouling rate and inlet pressure was next to backwash pressure. It seems that the fouling was strongly related to pressure which leads to the cake layer compression and adsorption of dissolved organic matter.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.117-126
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• 2020

Total knee arthroplasty is performed widely in degenerative arthritis of the knee joint, and the frequency of use is increasing. Efforts should be made to achieve functional recovery, such as returning to daily life, and the recovery of strength and range of motion after surgery. The procedure should be approached from a range of perspectives, such as patient factors, surgical technique and rehabilitation. The patient's age, degree of obesity, sex, and strength of the quadriceps muscle can affect the functional recovery after surgery. In addition, the patient's mental state, such as expectation value and satisfaction, can also have an effect. For functional recovery, patient education, pain control, and strengthening of the quadriceps muscle can be performed prior to surgery. Postoperative physiotherapy, such as icing and compression, transcutaneous electrical nerve stimulation therapy, neuromuscular electrical stimulation therapy, low frequency low intensity magnetic field therapy, strengthening of quadriceps muscle, and range of motion exercise can also be applied. In recent years, hydrotherapy, which restores the strength and balance of the leg, is being performed increasingly. These treatments are not only performed shortly after surgery, but are also performed continuously. In addition, the surgeon should apply it appropriately considering the patient's condition, compliance, and social and psychological conditions.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.675-679
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• 2008

Purpose: In the orbital floor fracture, sensory impairment due to the damage of the infraorbital nerve is one of the most common symptom and complication. In this report, we have the assumption that tailoring of $medpor^{(R)}$ for decompression may have correlations to the damage and regeneration of the nerve. Methods: Among patients who had open reduction for pure orbital floor fracture in our hospital from March 2005 to March 2008, we selected 80 cases. In 40 cases, we inserted tailored $medpor^{(R)}$, and in other 40 cases, non-tailored $medpor^{(R)}$ was inserted. Patient's reports were obtained and analyzed, and the pin-prick test and the 2-point discrimination test on the infraorbital nerve regions were done for testing the sensory impairments. Results: The results show that the patients who adopted sculpture of $medpor^{(R)}$ showed higher tendency of recovery of sensory impairments in the patient's subjective report, static touch sensation, static two point discrimination using. And in postoperative 3 months, there are statistically significant recovery of sensory symptoms, signs and the result of sensory tests. Conclusion: From these results, tailored $medpor^{(R)}$ in reconstruction of orbital wall fracture may improve recovery of sensory impairments for decreasing of compression of infraorbital nerve.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1473-1478
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• 2011

In this study, simulation and optimization works for a demethanizer column have been performed to obtain ethane and heavier products from a pretreated natural gas stream. Pretreated natural gas feed stream is partially condensed after being precooled by exchanging heat with demethanizer top vapor stream and by using an external refrigeration cycle with a propane refrigerant. Vapor stream is furtherly cooled and partially condensed through a turbo-expander and the power generated from the expansion of turbo-expander was delivered to the compressor for the residue gas compression. Liquid stream is being cooled by Joule-Thomson expansion valve and is fed to the middle section of the demethanizer. Ethane recovery percent for feed natural gas was set to 75% and methane to ethane molar ratio was fixed as 0.015. Propane refrigeration heat duty was reduced by splitting the feed stream and to exchange heat with side reboiler.