• Nuclear Engineering and Technology
• /
• v.52 no.8
• /
• pp.1650-1660
• /
• 2020

Comparing with the large containment, the gas can not flow freely within the local compartment due to the small volume of the compartment in case of serious accident, which affects the hydrogen flow distribution, and it will determines the location where high concentration occurs in compartment. In this paper, hydrogen distribution and possible hydrogen risk in the vessel under the different conditions are investigated. The results show that when the initial gas momentum is increased, the ability of gas enters into the upper region of the vessel will be strengthened, and the hydrogen volume fraction in the upper region of the vessel is higher. Comparing with horizontal source direction, when source direction is vertically towards upper space, hydrogen is more likely to accumulate in the upper region of the vessel. With the increasing of steam mass flow, the dilution effect of steam on the hydrogen volume fraction will be strengthened, while the pressure in the vessel is also increased. When steam flow is decreased, the hydrogen explosion risk is higher in the vessel. The experiment data can provide technical support for the validation of the CFD software and the mitigation of hydrogen risk in the containment compartment.

• Fire Science and Engineering
• /
• v.24 no.6
• /
• pp.145-152
• /
• 2010

A study on combustion efficiency concept was conducted for the under-ventilated fires in a fullscale ISO 9705 room. In particular, a comparison between global combustion efficiency (CE) measured outside the compartment and local CE measured at upper layer inside the compartment was focused. Heptane, toluene and iso-propanol were used to consider the wide ranges of heat of combustion and soot yield. As a result, the global CE was decreased linearly with increasing in global equivalence ratio (GER). On the other hand, the decreasing rate of local CE was increased gradually with increasing in GER. From these results, it was known that the information on local CE was very useful parameter to understand the fire phenomena inside the compartment. In addition, it was discussed that the local CE might be used as an important parameter in the process of scaling for the compartment fires.

• Journal of the Korean Society of Combustion
• /
• v.15 no.3
• /
• pp.32-39
• /
• 2010

An experimental study was conducted to investigate the relationship between global equivalence ratio(GER) and fire characteristics in an ISO 9705 room. Heptane fuel was burned with different fuel flow rates and doorway widths in order to force the room to be placed in different GER conditions. It was observed that after the onset of under-ventilated fire conditions, temperature and unburned fuel components such as CO and soot increased with increasing heat release rate (HRR), regardless of the doorway width. From the analysis of local mixture fraction, it was reconfirmed that the inclusion of soot production in the product composition was very important to predict accurately the chemical conditions inside the compartment, particularly for the under-ventilated fire conditions. In addition, the local equivalence ratio (LER) was directly proportional to the GER with a unit gradient regardless of doorway width when the soot production was included in the chemical products. This finding provided an important potential that the GER could be used to correlate the local thermal and chemical environment measured at the upper layer of a full-scale enclosure when soot was included.

• Archives of Plastic Surgery
• /
• v.46 no.1
• /
• pp.69-74
• /
• 2019

Background Local symptoms and signs of snake envenomation mimic the clinical features of compartment syndrome. It is important to measure the intracompartmental pressure to diagnose compartment syndrome. In this study, we present our experiences of confirming compartment syndrome and performing fasciotomy in snakebite patients based on high intracompartmental pressure findings. Methods The medical records of patients who visited the trauma center of Wonju Severance Christian Hospital from January 2010 to December 2015 for the management of venomous snakebite were retrospectively reviewed. Starting in 2014, fasciotomy was performed in patients with an intracompartmental pressure of more than 40 mmHg in addition to the clinical symptoms of compartment syndrome. Results A total of 158 patients with snakebite came to the hospital within 48 hours for treatment. Most patients (110 patients) were bitten at the upper extremities (69.6%). Since 2014, 33 out of 59 patients were suspected to have compartment syndrome, and their intracompartmental pressures were measured. Seventeen of those patients had a high intracompartmental pressure (average, 49.6 mmHg; range, 37-88 mmHg), and fasciotomy was performed. Conclusions In this study, as many as 10.8% of all cases were in need of fasciotomy when compartment syndrome was diagnosed by measuring the intracompartmental pressure. Previously, it was reported that fasciotomy was not required in many cases of compartment syndrome originating from snakebite. However, some patients may develop very severe compartment syndrome, requiring fasciotomy.

• The Korean Journal of Pain
• /
• v.13 no.1
• /
• pp.93-96
• /
• 2000

Background: Psoas compartment block with local anesthetics and corticosteroids is one of the treatments which provides long term analgesia of the lower back and anterior thigh unilaterally, and its technical easiness and safety allows blind application without C-arm guidance in the out-patient clinic. This study aimed to evaluate the mean of the depth from the skin to the psoas compartment, and its correlation to the following attributes: age, weight, height and PI (Ponderal Index). Methods: We investigated 28 patients who underwent psoas compartment block. All blocks were performed using Chayen's method (punctured at the point of 3 cm caudally and 5 cm laterally from the 4th lumbar vertebral spinous process) with a 22 G, 8 cm Tuohy needle under C-arm guidance. We recorded the depth from skin to the psoas compartment, height, weight and PI (weight (kg)/height (cm)$\times100$ (%)). Data were analyzed using the Pearson product-moment correlation coefficients. The correlations between the depth and other attributes identified by p-value of less than 0.05 were considered statistically significant. Results: The mean depths from skin to the psoas compartment were $6.02{\pm}0.28$ cm in men, $5.44{\pm}0.22$ cm in women. There is no significant correlation between the depth and other patient's attributes. Conclusions: The mean depths from skin to the psoas compartment may be one of the guide for psoas compartment block in outpatient clinics without C-arm guidance.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2001.10a
• /
• pp.172-172
• /
• 2001

• Journal of the Society of Naval Architects of Korea
• /
• v.54 no.4
• /
• pp.352-359
• /
• 2017

Because the Energy Efficiency Design Index(EEDI) came into effect in 2013, it is necessary to develop a new technology to overcome $CO_2$ emission regulations. In structural design viewpoint, lots of researches are carried out to develop eco-friendly and high fuel efficiency ships by weight reduction. By using the automated compartment arrangement system and automated structural design algorithm which were developed by the authors, new researches are performing to combine the above two systems. However, the effect of weight reduction was not significant because structural designs by using these systems for the midship part was carried out only focused on the minimum still water bending moment. In this paper, at first, good compartment arrangements which give the minimum still water bending moment and(or) shear force were chosen by using the automated compartment system. And then, influence of shear force on weight reduction was investigated by using the automated structural design algorithm considering longitudinal strength, local strength and shear strength of longitudinal members in cargo holds. Conclusively, it is necessary to consider the minimum still water bending moment and shear force simultaneously to reduce the weight of mid-sized bulk carrier. Also, good compartment arrangement which gives much more weight reduction compared with existing ship was proposed.

• The Korean Journal of Pain
• /
• v.30 no.1
• /
• pp.62-65
• /
• 2017

Reactivation of the latent varicella zoster virus in the sensory ganglion causes herpes zoster (HZ). Its characteristic symptom is a painful rash in the involved dermatome. HZ-induced motor weakness is rare and is usually resolved within one year of the onset, but some patients permanently experience motor dysfunction. Epidural steroid administration, with antiviral therapy, can be effective in treating pain from HZ and preventing postherpetic neuralgia. But an epidural block is contraindicated in patients receiving thromboprophylaxis. A psoas compartment block (PCB) provides equivalent analgesic efficacy with significantly low incidence of complication, compared to an epidural block. A 68 year old male patient recieving thromboprophylaxis presented with motor weakness following painful rash in his left L4 dermatome. Ten days before presentation, herpetic rash occurred on his left leg. We performed PCB with a steroid and local anesthetic, which successfully and safely alleviated the pain and motor weakness from HZ.

• Fire Science and Engineering
• /
• v.24 no.5
• /
• pp.32-38
• /
• 2010

Multi-dimensional fire dynamics were studied numerically with the change in ventilation conditions in a full-scale ISO 9705 room. Fire Dynamic Simulator (FDS) was used for the identical conditions conducted in previous experiments. Flow rate and doorway width were changed to create over-ventilated fire (OVF) and under-ventilated fire (UVF). From the numerical simulation, it was found that the internal flow pattern rotated in the opposite direction for the UVF relative to the OVF so that a portion of products recirculated to the inside of compartment. Significant change in flow pattern with ventilation conditions may affect changes in the complex process of CO and soot formation inside the compartment due to increase in the residence time of high-temperature products. The fire behavior in the UVF created complex 3D characteristics of species distribution as well as thermal and flow structures. In particular, additional burning near the side wall inside the compartment significantly affected the flow pattern and CO production. The distribution of CO inside the compartment was explained with 3D $O_2$ distribution and flow patterns. It was observed that gas sampling at local positions in the upper layer were insufficient to completely characterize the internal structure of the compartment fire.

• Fire Science and Engineering
• /
• v.26 no.2
• /
• pp.75-83
• /
• 2012

An experimental study was conducted to investigate the effects of change in heat release rate on unsteady fire characteristics of under-ventilated fire in a semi-closed compartment. A standard doorway width of the full-scale ISO 9705 room was modified to 0.1 m and the flow rate of heptane fuel was increased linearly with time using a spray nozzle located at the center of enclosure. Temperature, heat flux, species concentrations and heat release rate were continuously measured and then global equivalence ratio (GER) concept was adopted to represent the unsteady thermal and chemical characteristics inside the compartment. It was observed that there was a significant difference in unsteady behavior between global and local combustion efficiency, and the GERs predicted by ideal and measured heat release rate were also shown different results in time. The unsteady behaviors of temperature, heat flux and species concentrations were represented well using the GER concept. It was important to note that CO concentration was gradually decreased with the increase in GER after reaching its maximum value in the range of 2.0~3.0 of global equivalence ratio. In addition, the experimental data on unsteady thermal and chemical behaviors obtained in a semi-closed compartment will be usefully used to validate a realistic fire simulation.