• Fire Science and Engineering
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• v.28 no.6
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• pp.28-34
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• 2014

Two kinds of new piperazinomethyl-bis-phosphonic acid $M^{n+}$ ($PIPEABPM^{n+}$) were synthesized and their combustive properties of Pinus rigida plates treated with $PIPEABPM^{n+}$ were tested in comparison with the previously synthesized chemicals. Pinus rigida specimens were painted in three times with 15 wt% $PIPEABPM^{n+}$ solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). As a result, the combustion-retardation properties were partially increased by due to the treated $PIPEABPM^{n+}$ solutions in the virgin Pinus rigida. Especially, the specimens treated with $PIPEABPM^{n+}$ showed both the lower peak heat release rate ($HRR_{peak}$) (173.48~145.36) s and total heat release rate (THRR) (73.0~55.2) $MJ/m^2$ than those of virgin piperazinomethyl-bis-phosphonic acid (PIPEABP)-plate. Compared with virgin PIPEABP-plate, the specimens treated with the $PIPEABPM^{n+}$ showed low combustive properties. However the specimens treated with $PIPEABPM^{n+}$ showed both the shorter time to ignition (TTI) (58~18) s and the time to flameout (Tf) (564~456) s than those of virgin PIPEABP-plate by increasing the thermal conductivity.

• Fire Science and Engineering
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• v.27 no.5
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• pp.57-63
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• 2013

This study was performed to test the combustive properties of Pinus rigida plates treated with piperazinomethyl-bisphosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylenediaminomethyl- bis-phosphonic acid (MDEDAP). Pinus rigida specimens were painted in three times with 15 wt% alkylenediaminoalkyl- bis-phosphonic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). As a result, the combustion-retardation properties were increased by due to the treated alkylenediaminoalkyl-bis-phosphonic acid solutios in the virgin Pinus rigida. Especially, the specimens treated with chemicals showed both the later time to ignition (TTI) (148-116 s) and longer time to flameout (Tf) (633-529 s) than those of virgin plate by reducing the burnig rate. Compared with virgin pinus rigida plate, the specimens treated with the alkylenediaminoalkyl-bis-phosphonic acids showed partially low combustive properties. However the specimens treated with PIPEABP showed both the higher peak heat release rate (PHRR) (187.56 $kW/m^2$) and higher total heat release rate (THRR) (75.7 $MJ/m^2$) than those of virgin plate.

• Fire Science and Engineering
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• v.31 no.2
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• pp.37-43
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• 2017

The combustion characteristics of four kinds of wood specimens, such as Japan cedar, spruce, lauan, and red pine, were tested using the standards of Cone calorimeter (ISO 5660-1, 2) and smoke density tester (ASTM E 662). Japan cedar caught fire the quickest but the mean heat release rate was the lowest, $58.52kW/m^2$. The mean heat release rate of red pine appeared to be the highest, $71.75kW/m^2$. The lauan and Japan cedar generated relatively large amounts of carbon monoxide while the red pine and the spruce generated relatively large amounts of carbon dioxide. The red pine generated large amounts of smoke and the spruce generated the least amounts of smoke than the other samples. The total smoke release rate in the dynamic method was the highest in red pine and the lowest in spruce. The smoke density of red pine in the static method was highest in the non-flaming and flaming methods. In the non-flaming method, the smoke density of lauan was the second highest, whereas the flaming method was the least. In terms of the heat release rate, the fire risk from red pine was highest among the four test specimens. From the viewpoint of smoke generation, red pine was the most dangerous material in both dynamic and static methods.

• Fire Science and Engineering
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• v.30 no.4
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• pp.65-72
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• 2016

This study examined the generation of combustion toxic gases of pinus rigida specimens processed with bis-(dimethylaminomethyl) phosphinic acid (DMDAP), bis-(diethylaminomethyl) phosphinic acid (DEDAP), and bis-(dibutylaminomethyl) phosphinic acid (DBDAP). Each pinus rigida plate was coated three times with 15 wt.% flame retardants in an aqueous solution. The specimens were then dried at room temperature. The production of combustion toxic gases was investigated using a cone calorimeter (ISO 5660-1). The first time to peak mass loss rate ($1^{st}-TMLR_{peak}$) processed with the chemical additives decreased to 5.9 from 41.2% compared with the unprocessed specimen. The second time to the peak mass loss rate ($2^{nd}-TMLR_{peak}$) for the processed specimens was decreased 1.8% for DMDAP and 5.3% for DBDAP and increased 1.8% for DEDAP. The peak carbon monoxide ($CO_{peak}$) production was 1.5 to 2.0 times higher than that of the unprocessed plate. The peak carbon dioxide ($CO_{2peak}$) production was reduced 0.01 times for DMDAP and increased 1.15 to 1.19 times for DEDAP and DBDAP compared with the unprocessed specimens. In particular, the oxygen concentration was much higher than 15%, which can be fatal to humans and the resulting hazard can be eliminated. Overall, the combustion toxicity of flammable gas were increased partially by the chemical additives compared with those of the unprocessed plate.

• Fire Science and Engineering
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• v.22 no.5
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• pp.72-78
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• 2008

The mass loss rate and heat release rate of EPS sandwich panel cores were analysed using variable external irradiation level. The experimental materials were exposed to incident heat fluxes form 20 to 50 kW/$m^2$. For the measurement of mass loss rate and heat release rate, the size of specimen was $100mm{\times}100mm{\times}50mm$ and the samples were 3 different kinds. The combustion heat were carried out from the Oxygen bomb calorimeter and the mass loss rate and heat release rate were carried out from the Mass loss calorimeter according to ISO 5660-1. As the results of this study, the mass loss rate of Type A, B, and C were 2.7 g/$m^2s$, 2.8 g/$m^2s$, and 2.3 g/$m^2s$ and the heat release rate of Type A, B, and C were 58.23 kW/$m^2$, 47.19 kW/$m^2$, and 50.06 kW/$m^2$ respectively at the heat flux of 50 kW/$m^2$. In conclusion, when the heat release characteristics applied to a classification system of Canada, Type A and C can be classified grade C-3, and Type C can be classified grade C-2 from all data of this study.

• International Journal of Highway Engineering
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• v.8 no.4 s.30
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• pp.13-24
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• 2006

The stresses in concrete pavement systems are larger when vehicle loads are applied at pavement edges, and these large stresses significantly affect the behavior and performance of pavements. Therefore, in this study, the stress distribution and the critical stresses in concrete pavements were investigated using a finite element model when dual-wheel single-, tandem-, and tridem-axle loads were applied at pavement edges. First, the stress distribution along the longitudinal and transverse directions was analyzed, and then the effects of slab thickness, concrete elastic modulus, and foundation stiffness on the stress distribution were investigated. The effect of the tire contact pressure related to the tire print area was also studied. The location of the critical stress occurrence in concrete pavements was finally investigated. From this study, it was found that the critical concrete stress due to edge loads became larger as the concrete elastic modulus increased, the slab thickness increased, and the foundation stiffness decreased. The effect of the tire contact pressure on the critical stress was clear as the slab thickness became smaller. The critical stress location in the transverse direction was independent of the concrete elastic modulus and the foundation stiffness; however, it moved into the interior as the slab thickness increased. The critical stress location in the longitudinal direction was under the axle for single- and tandem-axle loads, but for tridem-axle loads, it tended to move under the middle axle from the outer axles as the concrete elastic modulus and/or slab thickness increased and the foundation stiffness decreased.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.478-485
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• 2015

The aim of this study is to analyze the combustion and thermal properties in order to establish baseline data for the fire safety evaluation of domestic timbers. The combustion properties such as heat release rate, total heat release, gas yield, and mass loss were analyzed by the method of cone calorimeter test and thermogravimetry (TGA). Thermal decomposition temperatures of the specimens by TGA were recorded as $359.83^{\circ}C$ for White pine, $359.80^{\circ}C$ for Red-Leaved Hornbeam, $363.14^{\circ}C$ for Carolina poplar, $358.59^{\circ}C$ for Konara oak, and $362.11^{\circ}C$ Sargent cherry. Red-Leaved Hornbeam showed the highest value of heat release rate, but, Carolina poplar wood showed the lowest value. In case of the total heat release, Red-Leaved Hornbeam wood showed the highest value and Carolina poplar wood showed the lowest one. The gas analysis results showed that Sargent cherry wood had the lowest value of 0.021, and Konara oak had the highest at 0.031 in the $CO/CO_2$. The minimum value of mass reduction was recorded as 87.57% for Sargent cherry, but, on the other hand, it was 95.03% for Konara oak. There was a correlation between the gas generation of CO and $CO_2$, and combustion behavior of woods. These results are expected to be usful for providing a fundamental guideline with the fire safety of wood use in interior applications.

• Land and Housing Review
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• v.2 no.2
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• pp.163-170
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• 2011

Individual Vacuum Pressure Method (IVPM) is a soft ground improvement technique, in which a vacuum pressure can be directly applied to the vertical drain board to promote consolidation and to strengthen the soft ground. This method does not require surcharge loads, different to embankment or pre-loading method. In this study, the ground improvement efficiency of Individual Vacuum Pressure Method was estimated when suction pressure increases step by step(-20, -40, -60, -80kPa) with different periods. During Individual Vacuum Pressure Method process, surface settlement and pore pressure were monitored, and cone resistance as well as water content were also measured after the completion of Individual Vacuum Pressure Method treatment. From the results, optimum duration of each step of vacuum pressure was determined, and the settlement was calculated using FEM numerical analysis.

• Journal of Mushroom
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• v.11 no.4
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• pp.208-213
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• 2013

The contents of raw materials which are components of mixed substrate for mushroom cultivation were analyzed to optimize the composition. The pure protein(amino acid) level of soybean meal was the highest, 44.02% followed by those of soybean curd residue(31.5%) and cotton seeds meal(30.6%). The non protein nitrogen(NPN) contents in crude protein of main nitrogen materials were 2.4% for soybean meal and 5.6% for dried soybean curd residue, while those of wheat bran and rice bran used as the carbon source were relatively higher, 17.6% compared to that of nitrogen supplying media. Crude protein content per price was 6.0 for rapeseed meal, indicating that it is high crude protein content per price. Nitrogen-free extract(NFE) considering as an ingredient for mycelial growth were high in alphacorn(72.9%) and wheat bran B(57.2%). Acid detergent fiber(ADF) was high in corncob, 51.88%, its use for cultivation of brown rot fungi including Lentinus lepideus should pay attention because the fungi lack complete lignin degradation activity.

• Journal of Internet Computing and Services
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• v.14 no.5
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• pp.27-38
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• 2013

Currently a number of managers exist to manage heterogeneous networks, in this situation, the NETCONF protocol for efficient network management has been proposed as a new protocol. However, the standard NETCONF protocol stack continuous improvement since the establishment but in four layers still have some problems. Especially in situations where there are multiple administrators, problems are more highlighted in operation layer. In this paper, we focus on these issues and the Operation layer has improved the efficiency and flexibility of operations among NETCONF four layers. Additionally, for the inefficiency of updates improved the device settings based on improved operation techniques. In addition, standard protocol NETCONF did not proposed content layer data structure and we propose standard technique of content layer that can generate configuration structure of devices. Improved the three techniques are applied appropriately to the NETCONF, the proposed method and the existing NETCONF was performed experiment to compare with experimental four factors. Compare key factor are four kind as maintaining the probability of network function, the reaction performance about command, the number of control packets, performance of data creation in content layer. Such factors after performing the experiment, the proposed method in this paper is superior to the existing NETCONF and there was confirmed by analysis Experimental results.