• Clean Technology
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• v.21 no.4
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• pp.229-234
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• 2015

Recently, there are increasing numbers of study regarding hydrogen fuels but researches on desulfurization of diesel are rare. In this study, we performed diesel desulfurization reactor design by computation fluid dynamics simulation. By analyzing the change in flow and sulfur concentration at the outlet according to the changes in flow rate, reactor length, and reactor diameter, we have found the minimum catalyst performance for the given flow rate condition and the relation between the reactor performance and the reactor size and shape. We also studied the effects of permeability of the packed bed on the flow and sulfur concentration distribution. The present work can be utilized to design a diesel desulfurization reactor for a fuel cell used in ships. Furthermore, the present work also can be used to design low sulfur diesel supply in oil refineries and therefore contribute to the development of clean petrochemical technology.

• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.348-353
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• 2020

A 68-year-old man presented with a bed sore with pus discharge on lower back. Radiographs showed extensive destruction of the L4 vertebral body. Magnetic resonance imaging (MRI) showed fluid collection with an enhanced wall at the defect of the L4 vertebral body extending into both psoas muscles. The primary diagnosis was neuropathic spondylopathy, but infective spondylitis was not ruled out. Initially, he was treated with antibiotics for two weeks. A follow-up MRI showed no improvement of the abscess, so surgical exploration was done. Charcot spinal arthropathy resulted in extensive vertebral body destruction that may be similar to infectious spondylitis, particularly in the case with fluid accumulation due to rupture of dura.

• Tunnel and Underground Space
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• v.23 no.3
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• pp.241-259
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• 2013

A packed bed thermal energy storage (TES) consisting of solid storage medium of rock or concrete through which the heat transfer fluid is circulated is considered as an attractive alternative for high temperature sensible heat storage, because of the economical viability and chemical stability of storage medium and the simplicity of operation. This study introduces the technologies of packed bed thermal energy storage, and presents a numerical model to analyze the thermal energy balance and the performance efficiency of the storage system. In this model, one dimensional transient heat transfer problem in the storage tank is solved using finite difference method, and temperature distribution in a storage tank and thermal energy loss from the tank wall can be calculated during the repeated thermal charging and discharging modes. In this study, a high temperature thermal energy storage connected with AA-CAES (advanced adiabatic compressed air energy storage) was modeled and analyzed for the temperature and the energy balance in the storage tank. Rock cavern type TES and above-ground type TES were both simulated and their results were compared in terms of the discharging efficiency and heat loss ratio.

• Journal of Industrial Technology
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• v.4
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• pp.37-41
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• 1984

Deposits of SiC has been formed by a chemical vapor deposition technique involving the application of gaseous mixture of $CH_3SiCl_3$ (MTS) and $H_2$ onto graphite substrate. These are non-fluid bed deposits prepared in an induction-heated reactor. From the experimental results, the deposition reaction of SiC is controlled by surface reaction mechanism at the temperature range between $1,100^{\circ}C$ and $1,400^{\circ}C$. The morphology of the SiC deposits changes from amorphous type to coarse, faceted structure as temperature increase.

• Journal of Korean Neurosurgical Society
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• v.47 no.5
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• pp.395-398
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• 2010

The majority of cases of pneumocephalus are secondary to trauma or medical intervention. Spontaneous, non-traumatic pneumocephalus is an uncommon condition. Most cases of spontaneous pneumocephalus require surgery. However, if there is no evidence of infection or cerebrospinal fluid leak, bed rest and follow-up imaging is an alternative treatment. Herein, we report a 31-year-old man with spontaneous pneumocephalus associated with pneumosinus dilatans.

• The Korean Journal of Pain
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• v.10 no.1
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• pp.104-108
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• 1997

Spontaneous intracranial hypotension, a syndrome of low CSF pressure, occurs without preceding events such as lumbar puncture, back trauma, operative procedure or medical illness. The most characteristic symptom is an occipital or frontal headache which is aggrevated in the erect position and relieved in the supine position. This syndrome usually resolves spontaneously or with strict bed rest. When the headach persists or is incapacitating, more aggressive treatment may be necessary. Autologous epidural blood patch is highly effective in the management of spontaneous intracranial hypotension. Epidural blood produces an organized clot which effectively tamponade any dural CSF leak. The rapid relief of headache immediately after the infusion of blood occur by some other mechanism, such as an increase in subarachnoid pressure that is known to occur with infusion of fluid into the lumbar epidural space. We report three cases of spontaneous intracranial hypotension successfully treated with epidural blood patch.

• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.1-6
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• 2009

An Overtopping Wave Energy Convertor (OWEC) is an offshore wave energy convertor used for collecting overtopping waves and converting the water pressure head into electric power through hydro turbines installed in a vertical duct affixed to the sea bed. A numerical wave tank based on the commercial computational fluid dynamics code Fluent is established for the corresponding analysis. The Reynolds Averaged Navier-Stokes equation and two-phase VOF model are utilized to generate the 2D numerical linear propagating waves, which are validated by the overtopping experiment results. Calculations are made for several incident wave conditions and shape parameters for the overtopping device. Both the incident wave periods and heights have evident effects on the overtopping performance of the OWEC device. The computational analysis demonstrates that the present overtopping device is more compatible with longer incident wave periods.

• Journal of the Korean Society of Combustion
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• v.17 no.1
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• pp.1-11
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• 2012

A slag building simplified model was developed to determine wall heat flux of a Shell 300 MW coal gasifier. In the model 4 layers(particulate, sintered, molten slag, solidified slag) were considered and mass conservation and energy balance were used to obtain each slag layer's thickness and surface temperature. Thermo-chemical and fluid charateristics of the gasifier were studied with and without considering the slag model using commercial CFD code FLUENT. Consideration of the slag layer did not affect syn-gas mole fractions. However, the slag layer caused to increase the exit gas temperature by about 50 K.

• Journal of Korean Neurosurgical Society
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• v.50 no.3
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• pp.274-276
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• 2011

Spontaneous cerebrospinal fluid (CSF) leak is a recognized cause of spontaneous intracranial hypotension (SIH). Subdural hematoma (SDH) is a serious but rare complication of SIH. An autologous epidural blood patch at the CSF-leak site can effectively relieve SIH. We report a case of bilateral SDH with SIH caused by a CSF leak originating at the C1-2 level. A 55-year-old male complained of orthostatic headache without neurological signs. His symptoms did not respond to conservative treatments including bed rest, hydration and analgesics. Magnetic resonance imaging showed a subdural hematoma in the bilateral fronto-parietal region, and computed tomography (CT) myelography showed a CSF leak originating at the C1-2 level. The patient underwent successful treatment with a CT-guided epidural blood patch at the CSF-leak site after trephination for bilateral SDH.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.60-66
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• 2013

The whole saltwort plant (Salicornia herbacea) was micronized to develop the table salt substitute. The micronized powder was mixed with distilled water and made into a spherical granule by using the fluid-bed coater (SGMPDW). The SGMPDW had superior flowability to powder; however, it had low dispersibility. To increase the dispersibility of SGMPDW, the micronized powder was mixed with the solution, which contained various soluble solid contents of saltwort aqueous extract (SAE), and made into a spherical granule (SGMPSAE). The SGMPSAE prepared with the higher percentages of solid content of SAE showed improved dispersibility in water and an increase in salty taste. The SGMPSAE prepared with 10% SAE was shown to possess the best physicochemical properties and its relative saltiness compared to NaCl (0.39). In conclusion, SGMPSAEs can be used as a table salt substitute and a functional food material with enhanced absorptivity and convenience.