• 한국전산유체공학회:학술대회논문집
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• 2008.10a
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• pp.262-267
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• 2008

Numerical investigations were performed with an external-compression inlet with a three-dimensional bump at Mach 2 to scrutinize the geometrical effects of the bump in controlling the interaction of a shock wave with a boundary layer. The inlet was designed for two oblique shock waves and a terminal normal shock wave followed by a subsonic diffuser, with a circular cross-section throughout. The bump-type inlet that replaced the aft ramp of the conventional ramp-type inlet was optimized with respect to the inlet performance parameters as well as compared with the conventional ramp-type inlet. The current numerical simulations showed that a bump-type inlet can provide an improvement in the total pressure recovery downstream of the shock wave/boundary layer interaction over a conventional ramp-type inlet.

• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.1
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• pp.43-50
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• 2005

This test was performed to evaluate the change of the unconfined compressive strength, strength parame¡?ters which resulted from direct shear test and oil residue percents analyzed by GC-MS as time lapse, oil addition. Unconfined compression strength of $10\%$ kerosene added by weight of dry soil recovered as time passed. In the case of $5\%$ kerosene added, the strength recovered as much as clean clayey soil after about 50 days passing. For the case of diesel added, the recovery of unconfined compressive strength was not shown even though about 60 days passed. The strength parameters (c, $\psi$) of kerosene added not changed but for diesel added, the cohesion was very decreased as diesel addition increased. Residual percent of kerosene in the soil was less than that of diesel as time passed.

• Journal of the Korean Institute of Gas
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• v.19 no.3
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• pp.9-17
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• 2015

Almost all of the natural gas consumed in South Korea is compressed into very high pressure for the transportation through the underground pipelines, then reduced in pressure regulation stations before delivery to the consumer. For pressure reduction, expansion valves have been used due to the simple and effective installation, but recover none of the energy in the gas during compression. Hence, turbo-expanders are proposed instead of the valves to accomplish the same pressure letdown function and recover some of the compression energy in the form of shaft work converting into electric powers. Here we have theoretically calculated the electric powers at the pressure reduction from 68.7 bar to 23 bar (which are the average values taken at the inlet and outlet points of the expansion valve in medium-pressure regulation stations) according to the inlet conditions of temperature and flow rate. The natural gas is considered as two cases of a pure methane and the mixture of hydrocarbons with a very small amount of nitrogen, and the Peng-Robinson equation of state is employed for the calculation of required thermodynamic properties. The electric energy is recovered as much as 1596 MW(methane) and 1567 MW(mixture) based on the total supply of natural gas in 2013.

• Journal of the Korean Wood Science and Technology
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• v.44 no.6
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• pp.842-851
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• 2016

The objective of this study was to improve physical and mechanical properties of soft-inner part of oil palm trunk (S-OPT) after impregnation with phenol formaldehyde (PF) resin and densification by close system compression (CSC) method. Effect of different methods of PF resin impregnation (i.e., no vacuum-pressure, vacuum, and vacuum-pressure) was evaluated. The results showed that PF resin impregnation and CSC significantly improved the physical and mechanical properties of S-OPT up to: (1) 176% in density; (2) 309% in modulus of rupture (MOR); (3) 287% modulus of elasticity (MOE); and (4) 191% in the compressive strength. Physical and mechanical properties of S-OPT showed their best performances when PF resin impregnated with vacuum-pressure method as shown by higher weight gain, density, MOR, MOE, compressive strength, and lower recovery of set due to better penetration of PF resin into S-OPT. Combining PF resin impregnation and densification by CSC method could be a good method to improve physical and mechanical properties of S-OPT.

• Journal of Veterinary Clinics
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• v.22 no.4
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• pp.297-301
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• 2005

This study was performed to evaluate the effects of the combination of electroacupuncture (EA) and surgical decompression on paraplegia due to spinal compression in dogs. Ten clinically healthy dogs were assigned into two groups (group A and group B). The one is for the combination of EA and surgical decompression, and the other is for surgical decompression alone. After decompression, neurological function was evaluated daily with modified Tarlov grading system. SEPs were measured as objective evaluation of normal spinal cord function before spinal compression and after neurological recovery. The period of rehabilitation in group A was significantly shorter than that in group B (p<0.05). Conduction velocity of SEPs showed a tendency to return to normal when the dogs got full recovery. According to these results, it was considered that the EA with surgical decompression was more effective than surgical decompression alone for paraplegia resulting from spinal cord injury in dog.

• Journal of Korean Neurosurgical Society
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• v.66 no.3
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• pp.324-331
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• 2023

Objective : We aimed to analyze the effectiveness of external neurolysis on the common peroneal nerve (CPN) in patients with posture-induced compressive peroneal neuropathy (PICPNe). Further, we aimed to examine the utility of magnetic resonance imaging (MRI) in assessing the severity of denervation status and predicting the postoperative prognosis. Methods : We included 13 patients (eight males and five females) with foot drop who underwent CPN decompression between 2018 and 2020. We designed a grading system for assessing the postoperative functional outcome. Additionally, we performed MRI to evaluate the denervation status of the affected musculature and its effect on postoperative recovery. Results : The median time to surgery was 3 months. The median preoperative ankle dorsiflexion and eversion grades were both 3, while the average functional grade was 1. Posterior crural intermuscular septum was the most common cause of nerve compression, followed by deep tendinous fascia and anterior crural intermuscular septum. There was a significant postoperative improvement in the median postoperative ankle dorsiflexion and eversion grades and average postoperative functional (4, 5, and 2.38, respectively). Preoperative ankle eversion was significantly correlated with denervation status. Additionally, the devernation status on MRI was positively correlated with the outcome favorability. However, denervation atrophy led to a less favorable outcome. Conclusion : Among patients with intractable PICPNe despite conservative management, surgical intervention could clinically improve motor function and functional ability. Additionally, MRI examination of the affected muscle could help diagnose CPNe and assess the postoperative prognosis.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.89-93
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• 2011

Purpose: We want to report on one patient who presented with lateral forearm pain caused by compression neuropathy of the lateral antebrachial cutaneous nerve. Materials and Methods: A female patient was managed by operative treatment (biceps tenoplasty) after failure with conservative treatment for 6 weeks. One year later, we evaluated the clinical symptoms and biceps tendon problems such as supination weakness or rupture after the tenoplasty. Results: Her symptom completely subsided immediately at the first postoperative day and her recovery was uneventful. Supination weakness and rupture of the distal biceps tendon were not found after the operation. Conclusion: We have reported here on a case of successful management of lateral antebrachial cutaneous neuropathy by performing biceps tenoplasty, along with a review of the previously published articles.

• Resources Recycling
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• v.26 no.4
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• pp.71-78
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• 2017

This study investigated the recovery of metallic aluminium in the black dross generated from used beverage can recycling process with crushing mechanism such as compression and impact. The as-received Al black dross had a spherical shape, and its size was about 10~40 mm. Also, The X-ray diffraction pattern showed that the main contents of black dross are composed of halite (NaCl), sylvite (KCl), spinel ($MgAl_2O_4$) and corundum ($Al_2O_3$). A metallic aluminium recovery test was performed using jaw crusher and hammer mill having different crushing mechanism. It was analysed that Jaw crushing process can separate into metallic aluminium and non metallic constituents. However, hammer milling process shows significant difference on the separation results. It was found that jaw crushing process was effective for recovery of metallic aluminium in the black dross than that of hammer milling process.

• Transactions of Materials Processing
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• v.14 no.4 s.76
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• pp.384-391
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• 2005

The nickel-based alloy Nimonic 80A possesses the excellent strength, and the resistance against corrosion, creep and oxidation at high temperature. Its products are used in aerospace engineering, marine engineering and power generation, etc. Control of forging parameters such as strain, strain rate, temperature and holding time is important because change of the microstructure in hot working affects the mechanical properties. Change of the microstructure evolves by recovery, recrystallization and grain growth phenomena. The dynamic recrystallization evolution has been studied in the temperature range of $950\~1250^{\circ}C$ and strain rate range of $0.05\~5s^{-1}$ using hot compression tests. The metadynamic recrystallization and grain growth evolution has been studied in the temperature range of $950\~1250^{\circ}C$ and strain rate range $0.05,\;5s^{-1}$, holding time range of 5, 10, 100, 600 sec using hot compression tests. Modeling equations are proposed to represent the flow curve, recrystallized grain size, recrystallized fraction and grain growth phenomena by various tests. Parameters in modeling equations are expressed as a function of the Zener-Hollomon parameter. The modeling equation for grain growth is expressed as a function of the initial grain size and holding time. The modeling equations developed were combined with thermo-viscoplastic finite element modeling to predict the microstructure change evolution during hot forging process. The grain size predicted from FE simulation results is compared with results obtained in field product.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.3
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• pp.73-84
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• 2022

Background : Lymphedema is a progressive disorder characterized by the impairment of lymph flow from tissues to the blood circulation system. This occurs as a result of damage to the lymphatic system. Complex decongestive therapy (CDT) is a multimodal, conservative therapeutic approach that is used for the management of lymphedema. CDT consists of a combination of compression therapy, manual lymphatic drainage, exercise, and skin care. Purpose : This study aimed to provide a review of available physical therapy interventions as well as general care guidelines for patients with lymphedema. Methods : The recommendations and guidelines for physical therapy management, medical management, and general information were reviewed from the following sources: 1) The American Physical Therapy Association, 2) The Norton School of Lymphatic Therapy, and 3) The International Society of Lymphology. This review contains general information, including the medical management and the importance of physical therapy in lymphedema. Physical therapy management should be based on an assessment of the patients' presenting impairments, including based on inclusion or exclusion of physical therapy interventions. This review also outlines a step-by-step approach that starts with disease diagnosis and progression all the way through to rehabilitation as an outpatient. Conclusion : Depending on the patients' journey to recovery and the requirement for rehabilitation, physical therapy interventions should focus on the patients' needs including pain, appearance, physical function and general rehabilitation. We hope that this review will provide information on evidence-based physical therapy and general care to patients with lymphedema.