• Journal of Navigation and Port Research
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• v.39 no.4
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• pp.285-291
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• 2015

Exposure to cold sea water can be life-threatening to the drowned individual. Although appropriate life jacket can be usually be provided for the buoyance at the drowning accident, heat loss can make the drowned individual experience the hypothermia. Inflatable life jackets filled with inflatable air pocket can increase the thermal protection as well as the buoyancy force. Because it is important to know how the human body behaves unde the different life jacket, present study compares the thermal insulation capacity of solid type life jacket with that of inflatable life jacket. In order to represent the insulation capacity of life jacket, thermal resistance is estimated based on the assumption of steady-state. Also, a transient three-dimensional thermal distribution of the thigh is analyzed by using finite element method implementing the Pennes bioheat equation. The finite element model is a segmental, multi-layered representation of the body section which considers the heat conduction within tissue, bone, fat and local blood flow rate.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.17 no.3
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• pp.189-202
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• 2013

Objectives The aim of this study is to analyze the characteristics of the tongue coating pattern in the elderly patients with xerostomia. Methods Ninety-six elderly patients with xerostomia were recruited by advertisement and they visited the oral diseases clinics at Kyung Hee University Korean Medicine Hospital and Kyung Hee University Hospital at Gangdong from November, 2011 to August, 2013. After signifying the assent, the subjects who passed screening were enrolled this study. The subjects were evaluated on their clinical characteristics of xerostomia using visual analogue scale for xerostomia, dry mouth questionnaire, unstimulated salivary flow rate. In addition, Yin-deficiency questionnaire was used to evaluate the Yin-deficiency state and Winkel tongue coating index and Digital Tongue imagin system were used to measure the tongue coating of patients. Results The proportion of women was higher than that of men, and there were few smokers in this study population. This population had chronic and relatively severe xerostomia symptoms. Also, thin coating pattern was showed in this elderly patients with xerostomia and this result was regarded to the influence of Yin-deficiency. The thin coating patten was observed in the group with higher Yin-deficiency score. There was no difference in tongue coating between the hyposalivation and normosalivation group. Conclusion In the elderly patients with xerostomia, Yin-deficiency is might be considered as one of the main cause of xerostomia. Hence, it is thought that this patients showed the thin coating pattern. This results could be used in diagnosis and treatment for the elderly patients with xerostomia in traditional Korean medicine.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.47-58
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• 2011

Halogen free intumescent flame retardants(IFRS), such as the mixture of melamine phosphate(MP) and char forming agents(pentaerythritol(PER), di-pentaerythritol(DiPER), tris(2-hydroxyethyl) isocyanurate(THEIC)), were prepared and characterized. Polypropylene(PP)/$IFR_S$ composites were also prepared in the presence of ethylene diamine phosphate(EDAP) as a synergist and used into flame retardant PP powder coatings. Thermoplastic PP powder coatings at 20 wt% flame retardant loading were manufactured by extruded and then mechanical cryogenic crushed to bring them in fine powder form. These intumescent flame retardant powder coatings($IFRPC_S$) were applied on mild steel surface for the purpose of protection and decorative. It is a process in which a $IFRPC_S$ particles coming in contact with the preheated mild steel surface melt and form a thin coating layer. The obtained MP flame retardant was analyzed by utilizing FTIR, solid-state $^{31}P$ NMR, ICP, EA and PSA. The mechanical properties as tensile strength, melt flow index(MFI) and the thermal property as TGA/DTA and the fire safety characteristics as limiting oxygen index(LOI), UL94 test, SEM were used to investigate the effect of $IFRPC_S$. The experimental results show that the presence of $IFR_S$ considerably enhanced the fire retardant performances as evidenced by the increase of LOI values 17.3 vol% and 32.6 vol% for original PP and $IFRPC_S$-3(PP/MP-DiPER/EDAP), respectively, and a reduction in total flaming combustion time(under 15 sec) in UL94 test of $IFRPC_S$. The prepared $IFRPC_S$-3 have good comprehensive properties with fire retardancy 3.2 mm UL94 V-0 level, LOI value 32.6%, tensile strength $247.3kg/cm^2$, surface roughness Ra $0.78{\mu}m$, showing a better application prospect. Through $IFRPC_S$-2(PP/MP-PER/EDAP) and $IFRPC_S$-3 a better flame retardancy than that of the $IFRPC_S$-1(PP/MP/EDAP) was investigated which was responsible for the formed more dense and compact char layer, improved synergy effect of MP and PER/DiPER.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3220-3226
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• 2011

In order to monitor internal risk factors such as fire, terror, etc. on the subway station, the surveillance systems using CCTV and various kinds of sensors have been implemented and recently, introduction of surveillance systems using an advanced IT technology, sensor network technology is tried on several areas. Since 2007, Korean government has made an effort to develop the intelligent surveillance and monitoring system, which can monitor fire, intrusion, passenger congestion, health-state of structure, etc., by using wireless sensor network technology and intelligent video analytic technique. For that purpose, this study carried out field wireless communication environment test on Chungmuro Station of Seoul Metro on the basis of ZigBee that is considered as a representative wireless sensor network before field application of the intelligent integrated surveillance system being developed, arranged and analyzed and ZigBee based wireless communication environment test results on the platform and waiting room of Chungmuro Station on this paper. Results of wireless spectrum analysis on the platform and waiting room showed that there is no radio frequency overlapped with that of ZigBee based sensor network and no frequency interference with adjacent frequencies separated 10MHz or more. As results of wireless data transmission test using ZigBee showed that data transmission is influenced by multi-path fading effect from the number and flow rate of passengers on the platform or the waiting room rather than effects from entrance and exit of the train to/from the platform, it should be considered when implementing the intelligent integrated surveillance system on the station.

• Journal of the Korean Institute of Gas
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• v.7 no.2 s.19
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• pp.22-32
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• 2003

Al-brass material is generally used at the state of plastic deformation, for example; bending, extension of bell mouth at shell and tube type heat exchanger. And SCC(stress corrosion cracking) of Al-brass material will be affected by residual stress as plastic deformation. SCC results from synergism between mechanical factor and corrosion environment. Mechanical factor is stress that directly relates with stress intensity factor at the crack tip. This paper was studied on the effect of stress on SCC of Al-brass tube under in $3.5\%$ NaCl. + $0.1\%\;NH_4OH$ solution by constant displacement tester. Increasing of acidified water flow into sea and speeds up corrosion rate of Al-brass which is used as a tube material of vessel heat exchanger by polluted coast seawater. The experimental results are as follow The latent time of SCC occurrence gets longer as the initial stress intensity factor($K_{Ii}$) gets lower The main crack was propagated as the initial stress intensity factor($K_{Ii}$) gets higher, and secondary cracks occurred by electro-chemical factor a(ter stage of released stress. Dezincification phase showed around the crack, and the range of dezincification gets wider as the initial stress intensity factor($K_{Ii}$) gets higher.

• Journal of Soil and Groundwater Environment
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• v.10 no.4
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• pp.54-61
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• 2005

An aquifer thermal energy storage (ATES) system can be very cost-effective and renewable energy sources, depending on site-specific parameters and load characteristics. In order to develop the ATES system which has certain hydrogeological characteristics, understanding the thermohydraulic process of an aquifer is necessary for a proper design of an aquifer heat storage system under given conditions. The thermohydraulic transfer for heat storage was simulated according to two sets of simple pumping and waste water reinjection scenarios of groundwater heat pump system operation in a two-layered aquifer model. In the first set of the scenarios, the movement of the thermal front and groundwater level was simulated by changing the locations of injection and pumping wells in a seasonal cycle. However, in the second set the simulation was performed in the state of fixing the locations of pumping and injection wells. After 365 days simulation period, the shape of temperature distribution was highly dependent on the injected water temperature and the distance from the injection well. A small temperature change appeared on the surface compared to other simulated temperature distributions of 30 and 50 m depths. The porosity and groundwater flow characteristics of each layer sensitively affected the heat transfer. The groundwater levels and temperature changes in injection and pumping wells were monitored and the thermal interference between the wells was analyzed to test the effectiveness of the heat pump operation method applied.

• Membrane Journal
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• v.15 no.1
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• pp.52-61
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• 2005

Permeate flux decline in a microfiltration was analyzed by measuring the permeability of bentonite colloidal solution through polyethylene capillary membranes. The flux decline with time was due to the growth of cake layer on the membrane surface and to the pore blocking by particles. As the time approaches to steady state, the permeate flux is almost controlled by the cake filtration model. Faster flux decline at high trans-membrane pressure was attributed to the formation of denser packed cake layer and pore blocking. The ratio of permeate flux to the initial permeate flux, J/J₁, decreased with increasing the trans-membrane pressure, from 45% for 0.5 kg/sub f//㎠ to 38% for 2.0 kg/sub f//㎠. In comparing the ratio of each fouling component to the total fouling for the 0.5 kg/sub f//㎠ TMP condition, complete blocking was 23.4%, standard blocking was about 14.6% and cake filtration was 62.0%, respectively. Permeate flux through the membrane increases with cross flow velocity, and the effect of the variation of velocity is more significant at 1.0 kg/sub f//㎠ rather than at 2.0 kg/sub f//㎠ of the operation pressure. Permeate flux for the membrane having the average pore diameter of 0.34 ㎛ was higher than that for the membrane of 0.24 ㎛ pore size, with the higher flux with the low concentration of feed. On the operation using the membrane of 0.34 ㎛ pore, the pore blocking in the low concentration of 200 ppm is negligible relative to the pore blocking in the 1000 ppm feed.

• Journal of Veterinary Clinics
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• v.30 no.2
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• pp.87-94
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• 2013

This retrospective study reviewed the clinical and diagnostic features, therapeutic outcome and compilations of interventional ductal occlusion in 37 dogs with patent ductus arteriosus (PDA). Malteses and female dogs were over-presented. Bounding pulse and left basal continuous murmur were most common findings in physical examination, while the differential cyanosis was rarely observed. Left ventricular (LV) enlargement patterns and sinus tachycardia were common in the ECG. Typical radiographic findings included LV elongation and triple bumps indicating left atrial (LA), aortic and pulmonary dilation. Echocardiographic features were typical shunt flow at the ductus arteriosus and marked LV dilation with mild to moderate mitral regurgitation (MR). The 32 of 37 dogs were interventionally treated with either thromboemolic coils (TCE) or Amplatz canine ductal occluder (ACDO). Transient hemoglobinuria caused by incomplete closure was occurred in 2 dogs treated with TCE, although the hemoglobinuria was disappeared within a week of intervention. The dislodgement of occlusion device was occurred in 2 dogs with TCE and 1 dog with ACDO. However there were no significant complications associated with this dislodgement, since those were dislodged at the lower pulmonary vasculature. We also found that no serious complications and no further medical intervention in 29 dogs having long-term follow-ups.

• The Journal of Pediatrics of Korean Medicine
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• v.22 no.1
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• pp.69-93
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• 2008

Objectives The purpose of this study is to investigate the effect of KKHS on atopic dermatitis in an in-vivo experiment using an NC/Nga atopic dermatitis mouse, which has histological and clinical similarities to this condition in humans. Methods To investigate the effect of KKHS on atopic dermatitis (AD), we evaluated atopic dermatitis-like skin lesions by clinical skin index and analyzed immunological parameters in peripheral blood mononuclear cells(PBMCs), splenocytes, draining lymph node(DLN) and performed skin histology in ears and dorsal skin of atopic dermatitis of NC/Nga mouse in vivo. Results In vivo, clinical skin severity score was significantly lower in the KKHS group than in the control group. IgE, IL-6, TNF-${\alpha}$, IgM, IgG2a and IgG2b levels in serum decreased remarkably in the KKHS group than in the control group, and the level of IFN-${\gamma}$ production which is secreted from Th1 cell was increased by KKHS. After this experiment we analyzed immunological cells ($CD3^+$, $CD19^+$, $CD4^+$, $CD8^+$, $CD3^+CD69^+$, $CD4^+CD25^+$ and $CD49b^+$) by flow cytometry. It results that the total absolute number of $CD3^+$, $CD19^+$, $CD4^+$ and $CD8^+$ cells were recovered as much as normal state, and the level of $CD3^+CD69^+$ in isolated DLN and PBMCs were significantly decreased, and total absolute number of $Gr-1^+$, $CD11b^+$ and $CD3^+$ in dorsal skin of NC/Nga mouse were decreased by KKHS. We analyzed ear, DLN, and neck-back skin after biopsy and dyeing by hematoxyline/eosin(H&E), toluidine staining (mast cells marker). KKHS were very effective to the histological symptoms which are in dermal and epidermal thickening, hyperkeratosis and inflammatory cell infiltration. Ear thickness was significantly decreased compared with the control group and the size of inflammatory lymphocytes cells (ILC) and plasma cells (PC) in DLN were also decreased. Conclusions KKHS on atopic dermatitis in an in-vivo experiment using an NC/Nga atopic dermatitis mouse was very effectiveness to the atopy dermatitis treatment.

• Journal of Energy Engineering
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• v.15 no.4 s.48
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• pp.277-283
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• 2006

In this study, butane 100% was used as fuel to verify the real fuel effect such as vapor pressure variation due to temperature change. A MPI fuel injection system for V-6 engine, which has reverse 'L' type cross section to minimize the possibility of liquid phase injection, was composed and one bank was operated under sequential injection scheme. Flow rate were measured according to injection duration, interval, and pressure. Also occurring of liquid phase injection was monitored with varying vaporizer and fuel rail temperature. The result shows that basic characteristics of injection is a relatively difference between air and LPG injection. Under cold start condition, however, the occurrence of liquid injection becomes more severe as the pressure increases, and sufficiently high temperature both in vaporizer and fuel rail is very important to insure gaseous injection. In addition, the temperature of vaporizer plays more important role in keeping LPG vapor state and the reverse 'L' type cross section of the rail is available to prevent liquid injection.