• Fire Science and Engineering
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• v.33 no.1
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• pp.39-44
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• 2019

In this study, the relationships between the material properties of the wall and the fuel mass flux in compartment fire. The fire resistant board (fire-board) and steel plate compartments are constructed with a 0.3 m width, 0.5 m height and 3.0 m length. To obtain the mass loss rate considering the location of the fire origin in compartment, experiments of a heptane pool fire are performed with a combustion area of $0.01m^2$ and $0.0225m^2$. The results show that the initial mass flux of heptane, $0.0087kg/m^2{\cdot}s$, is increased to $0.166kg/m^2{\cdot}s$ for fire board and $0.019kg/m^2{\cdot}s$ for steel plate. It means that the fire-scenario should be considered with the thermal characteristics of the material properties and geometric shapes of the compartment to predict fire propagation accurately in a compartment space.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.375-384
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• 2023

Most Hepatic hemangiomas are asymptomatic and small in size, making them difficult to find by pathological examination. Therefore, radiological diagnosis is essential for the early finding and diagnosis of Hepatic hemangioma. Three-phase method using contrast medium in computed tomography, T1, T2-weighted imaging in magnetic resonance imaging, dynamic magnetic resonance imaging using contrast medium, echo planar imaging method, diffusion-weighted imaging method, blood pool scan using ^99mTc-labeled red blood cells in nuclear medicine, we looked at the color doppler method In ultrasound, and it is important to accurately understand the imaging findings of hepatic hemangioma and perform the examination in order to make an accurate diagnosis. most hepatic hemangioma are benign tumors, care should be taken not to confuse them with malignant tumors such as hepatocellular carcinoma to prevent unnecessary procedures. Therefore, in order to make an accurate diagnosis, it is important to accurately understand the imaging findings of hemangioma and perform the examination.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.353-360
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• 1984

As an effort to expand the utilization of mackerel which has been thought disadvantageous to processors due to the defects in bloody dark color of meat, high content of lipid, and low stability of protein, and to develope a new type of product, so called, preservative fish meat paste, the processing method was studied in which dielectric heating was applied by means of cooking, pasteurization, dehydration, and control of water activity. The principle of this method is based on that dielectric heating can initiate a rapid dispersion or displacement of moisture in the meat tissue so that the level of water acivity can be controlled by dehydration with hot air meanwhile the product is cooked, pasteurized, and texturized. And the product is finally heated with electric heaters and vacuum sealed to stabilize water activity and storage stability. In present paper, a formula for preparing the fish meat-stach paste, the conditions of dielectric heating and dehydration, shape and size of the product, and other parameters were tested to optimize the process operation. A formula of the fish meat-starch paste to provide proper textural properties and water activity was $10\%$ starch, $1.5\%$ salt, $3\%$ soybean, $0.6\%$ MSG, $2\%$ sucrose, and $3\%$ sorbitol against the weight of fish meat. A proper shape and size of the product to avoid foaming and case hardening during heating was sliced disc of 8 cm $diameter{\times}0.8$ cm thickness or $10{\times}10$ cm square plate with 1.0 cm thickness. The disc shape was recommended because it resulted more uniform heating, minimum foaming and case hardening. And it was also advantageous that disc was simply provided when the fish meat disc was stuffed in the same, solidified in boiling water for 2 to 3 minutes, and sliced. Condition of dielectric heating was critical to decide the levels of sterility, water activity, and textural property of the product. The temperature at the center of the meat disc slices was raised up to $95^{\circ}C$ in 1.5 minutes so that continuous exposure to microwave caused expanded tissue and hardening ending up with a higher water content. Heating for 5 to 6 minutes was adequate to yield the final water activity of 0.86 to 0.83(35 to $40\%$ moisture). It is important, however, that heating had to be done periodically, for instance, in the manner of 2.0, 1.5, 1.5, and 1.0 minute to give enough time to displace or evaporate moisture from the meat tissue. The product was dehydrated for 2 to 3 minutes by hot air of $60^{\circ}C$, 3 to 5m/sec and finally exposed to electric heaters for 5 to 6 minutes until the surface was roasted deep brown. These conditions of heating and dehydration resulted in a complete reduction of total plate count from an initial count of $5.3{\times}10^6/g$ to less than $3{\times}10^2/g$. General composition of the product was $40.1\%$ moisture, $20.8\%$ protein, $17.4\%$ lipid, $16.2\%$ carbohydrate, and $5.5\%$ ash. Textural properties revealed folding test AA, hardness 42, cohesiveness 0.53, toughness 4.6, and elasticity 0.8.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.4
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• pp.48-59
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• 2014

This study was carried out to present raw data on managing the restored urban stream by studying the naturalized plants distributed in Gaeumjeong Stream, Changwon-si, Gyeongsangnam-do, Korea. The results were as follows. The numbers of naturalized plants were summarized as 45 taxa including 17 families, 36 genera, 43 species and 2 varieties. The invasive alien plants were 2 taxa including Ambrosia artemisiifolia and Lactuca sativa. The following summarizes the attributes of the naturalized plants. Most of the plants commonly originated from Europe and North America. The 5 naturalized degree that was widely distributed and had many individual was the most common. Until 1921, after the opening of 1 period was the most common in the introduced period. Section 12 had the highest NI at 41.9%, and the lowest, at 20.5%, in sections 9 and 19 were analyzed. Section 1 had the highest UI at 6.2%, whereas, the lowest, at 2.5%, was calculated in sections 19 and 20. Section 2 showed the highest DI at 16.7%. The first results of the analysis of the causes for the invasion of naturalized plants on the riverside and waterways, and physical factors and maintenance are directly affected. Second, sewage, muddy water and sediment deposits this naturalized plant caused by a chemical factor. Third, it is thought that invasive alien plants are irregular as it happens in biological factor. The proposed management plan naturalized plants, the first, disturbance caused by species management is a young object is removed immediately before flowering scape to eliminate or suppress the propagation of physical methods will be needed. Second, the fact that the national spread of native plant species and planting management does not provide space for the growth is very important. Third, agricultural land is disturbed by agricultural practices by interfering with the action of naturalized plants because the source of the river should be prohibited in agriculture. In the future, if we studied the naturalized plants distributed in restored streams located in Changwon-si, the characteristics of change in the ecosystem impact is expected to be beneficial.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.113-130
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• 2002

In this paper, we developed DNL(Dynamic Network Loading) model based on Moving cell theory to analyze the dynamic characteristics of traffic flow in congested network. In this paper vehicles entered into link at same interval would construct one cell, and the cells moved according to Cell following rule. In the past researches relating to DNL model a continuous single link is separated into two sections such as running section and queuing section to describe physical queue so that various dynamic states generated in real link are only simplified by running and queuing state. However, the approach has some difficulties in simulating various dynamic flow characteristics. To overcome these problems, we present Moving cell theory which is developed by combining Car following theory and Lagrangian method mainly using for the analysis of air pollutants dispersion. In Moving cell theory platoons are represented by cells and each cell is processed by Cell following theory. This type of simulation model is firstly presented by Cremer et al(1999). However they did not develop merging and diverging model because their model was applied to basic freeway section. Moreover they set the number of vehicles which can be included in one cell in one interval so this formulation cant apply to signalized intersection in urban network. To solve these difficulties we develop new approach using Moving cell theory and simulate traffic flow dynamics continuously by movement and state transition of the cells. The developed model are played on simple network including merging and diverging section and it shows improved abilities to describe flow dynamics comparing past DNL models.