• Transactions of the Korean hydrogen and new energy society
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• v.10 no.1
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• pp.41-48
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• 1999

The heat transportation from a complex of industry to a rural area needs more efficient method because the distance between them is usually more than 10km. Conventional heat transportation using steam or hot water via pipe line has limits in transportation distance (about 3-5 km) because of the heat loss and frictional loss in the pipe line. Metal hydride can absorb or discharge hydrogen through exothermic and endothermic reaction. After releasing hydrogen from metal hydride with heatings by waste heat from industry we can transport this hydrogen to the rural area via pipe line. In the urban areas other metal hydride reacts with this hydrogen and produces heat for heating. Cool heat is also obtained if it is possible to use metal hydride with low reaction temperature. So metal hydride can be used as a media for transportation, storage of heat. Some problems of the heat transportation using metal hydrides, and the example of heat transportation system were discussed.

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.16-22
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• 2015

Alkaloids of Vinca minor L. were characterized by HPLC equipped with the photo diode array detector and compared their UV/vis absorption spectra with an index material such as vincamine. UV/vis absorption spectra of more than 9 compounds belong to various classes such as flavonoids were shown and characterized. Extracts with ethanol or hot water were tested against the DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical to investigate their antioxidant activity. Based on the results, those extracts show about 14-15% of antioxidant activity of quercetine and vitamin C used as standards.

• The Korean Journal of Food And Nutrition
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• v.33 no.6
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• pp.666-671
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• 2020

To analyze the quality characteristics of soybean (Glycine max), the approximate analysis, physical properties, mineral and free sugar content of domestic soybean cultivars were analyzed. The moisture content was about 9.15~11.84%. The fat content of Cheonga, Taekwang, and Jinpung cultivars were 17.93~18.37%, which was significantly higher than that of others. Protein content of Cheonga and Seonyu were 36.15~36.70%, significantly higher than that of others. As for the weight and shape of soybeans, the Daewon was the largest allele, and the seed cover ratio was the highest in the Seonyu. In terms of water absorption rate, the Seonyu showed the highest absorption rate at 246.19%, and the Daewon showed the lowest absorption rate. Soaked soybeans had a hardness of 2.80~4.73 kg/㎠, which did not show low hardness in the sample with high moisture absorption. The grinded soybeans showed higher lightness and yellowness values than the raw soybeans, and the redness was decreased. Soybean minerals contained high K, P, Mg, and Ca content. Overall, The Taekwang contained more minerals than others. Stachyose, sucrose, glucose and fructose were detected as free sugars in soybeans. The total free sugar content of Taekwang was the lowest at 3.47%, and the Cheonga (6.80%) was the highest.

• Journal of Environmental Science International
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• v.23 no.3
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• pp.511-520
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• 2014

The MFFn(Mass first flush), EMCs(Event mean concentrations) and runoff loads were analyzed for various rainy events(monitoring data from 2011 to 2012) in transportation area(rail road in station). The pollutant EMCs by volume of stormwater runoff showed the BOD5 9.6 mg/L, COD 29.9 mg/L, SS 16.7 mg/L, T-N 3.271 mg/L, T-P 0.269 mg/L in the transportation areas(Railroad in station). The average pollutant loading by unit area of stormwater runoff showed the BOD5 $27.26kg/km^2$, COD $92.55kg/km^2$, SS $50.35kg/km^2$, T-N $10.13kg/km^2$ and T-P $10.13kg/km^2$ in the transportation areas. Estimated NCL-curve(Normalized cumulated-curve) was evaluated by comparison with observed MFFn. MFFn was estimated by varying n-value from 10% to 90% on the rainy events. The n-value increases, MFFn is closed to '1'. As time passed, the rainfall runoff was getting similar to ratio of pollutants accumulation. The result of a measure of the strength of the linear relationship between observed data and expected data under model was good.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.515-524
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• 2015

The number of occurrence of differential settlement and track irregularity at track transition zone recently comes to increase, which leads to frequent maintenance activities that have an impact on train operation. Such track transition zone damages are attributed to the change of mechanical properties of fill materials due to environmental factors such as rainfall and freeze, and thaw. Consequently, this study attempts to establish the soil water characteristic curve (SWCC) of fill materials, and conduct seepage analysis to assess the distribution of degree of saturation (DOS) for track transition zone in case of rainfall. The SWCC of fill materials was successfully obtained using filter paper test method. The results of seepage analysis revealed that rainfall intensity, the slope of backfill, backfill condition (fill or cut), and SWCC are significantly influential in controlling the distribution of DOS.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.5
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• pp.379-384
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• 2013

For effective ship management in VTS(Vessel Traffic Service), it needs to assess the external force acting on ship. Big data in maritime traffic can be roughly categorized into two groups. One is the traffic information including ship's particulars. The other is the external force information e.g., wind, sea wave, tidal current. This paper proposes the method to assess the external force acting on ship using big data in maritime traffic. To approach Big data in maritime traffic, we propose the Waterway External Force Code(WEF code) which consist of wind, wave, tidal and current information, Speed Over the Water(SOW) of each ship, weather information. As a results, the external force acting a navigating ship is estimated.

• Journal of Families and Better Life
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• v.26 no.2
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• pp.83-101
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• 2008

This research performs a multi comparison between the age of old households and the economic structure according to accommodation type as well as analyzing the economical structural difference of each type based on the features of aged households. The paper classified aged households into 3 groups according to age distribution. The economic structure analysis according to the age of old households and accommodation type was shown as follow: First, the economical structural analysis based on the age of old households showed a statistical difference in the total, labor, business, property and transfer income variables according to the age of each sample group. However, the non-business income and liabilities did not show a significant difference. Second, in the analysis of different economic earnings and initial expenses of middle-aged households according to the age distribution group showed a disparity in the total, labor, business, property, and transfer income variables according to the age of each sample group. However, aged households showed a statistical difference in total, labor, business and transfer income variables. Third, in the analysis of difference in the expense provision and size of consumption, there was a statistical difference in the expense variables of total consumption, food, dining out, electricity, water, furniture, kitchen supplies, clothing, shoe, education, culture, entertainment, transportation, and communication. Fourth, in the analysis of difference in the size of consumption expense, the initial and middle-aged households showed a statistical difference in the total consumption, food, dining out, electricity, water, furniture, kitchen supplies, clothing, shoe, education, culture, entertainment, transportation, communication, and consumption expense variables. However, the analysis of aged households has shown a statistical difference in the total consumption, food, dining out, electricity, water, furniture, kitchen supplies, clothing, shoe, education, culture, entertainment, transportation, and communication expense variables. The study found a statistical difference in the expense for hygienics that did not appear in the initial and middle-aged households.

• Earthquakes and Structures
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• v.17 no.4
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• pp.411-424
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• 2019

In this study, a numerical model of a shield tunnel with an assembled segmental lining was built. The seismic response of the segmental lining of the section of the shield tunnel in Line 1 of the Chengdu Metro is analyzed as it passes through the interface of sand-cobble and mudstone layers. To do so, the node-stress seismic-motion input method was used to input the seismic motion measured during the 2008 Wenchuan earthquake, and the joint openings and dislocations associated with the earthquake action were obtained. With reference to the Ethylene-Propylene-Diene Monomer (EPDM) sealing gaskets used in the shield tunnels in the Chengdu Metro, numerical simulation was applied to analyze the contact pressure along the seepage paths and the waterproof property under different joint openings and dislocations. A laboratory test on the elastic sealing gasket was also conducted to study its waterproof property. The test results accord well with the numerical results and the occurrence of water seepage in the section of the shield tunnel in Line 1 of the Chengdu Metro during the 2008 Wenchuan earthquake was verified. These research results demonstrate the deformation of segmental joint under earthquake, also demonstrate the relationship between segmental joint deformation and waterproof property.

• Geomechanics and Engineering
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• v.36 no.3
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• pp.259-276
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• 2024

The undrained shear strength is widely acknowledged as a fundamental mechanical property of soil and is considered a critical engineering parameter. In recent years, researchers have employed various methodologies to evaluate the shear strength of soil under undrained conditions. These methods encompass both numerical analyses and empirical techniques, such as the cone penetration test (CPT), to gain insights into the properties and behavior of soil. However, several of these methods rely on correlation assumptions, which can lead to inconsistent accuracy and precision. The study involved the development of innovative methods using extreme gradient boosting (XGB) to predict the pile set-up component "A" based on two distinct data sets. The first data set includes average modified cone point bearing capacity (q_t), average wall friction (f_s), and effective vertical stress (σ_vo), while the second data set comprises plasticity index (PI), soil undrained shear cohesion (S_u), and the over consolidation ratio (OCR). These data sets were utilized to develop XGBoost-based methods for predicting the pile set-up component "A". To optimize the internal hyperparameters of the XGBoost model, four optimization algorithms were employed: Particle Swarm Optimization (PSO), Social Spider Optimization (SSO), Arithmetic Optimization Algorithm (AOA), and Sine Cosine Optimization Algorithm (SCOA). The results from the first data set indicate that the XGBoost model optimized using the Arithmetic Optimization Algorithm (XGB - AOA) achieved the highest accuracy, with R2 values of 0.9962 for the training part and 0.9807 for the testing part. The performance of the developed models was further evaluated using the RMSE, MAE, and VAF indices. The results revealed that the XGBoost model optimized using XGBoost - AOA outperformed other models in terms of accuracy, with RMSE, MAE, and VAF values of 0.0078, 0.0015, and 99.6189 for the training part and 0.0141, 0.0112, and 98.0394 for the testing part, respectively. These findings suggest that XGBoost - AOA is the most accurate model for predicting the pile set-up component.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.321-329
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• 2015

This study investigates effects of hardware and telecommunication and software service divided by ICT service on each 5 transportations to explore convergence of ICT and Transportation. Research models are production inducing effects, Added Value inducing effects of Demand-Driven model and Shortage cost effects of Supply-Driven model by using data for 2010~2012 of Input-Output Table. Results are that network and software service effects are more impact than hardware effects on transportations. Especially, hardware is impacted heavily on production inducing effect, telecommunications and software services has had a significant impact on the production inducing effect and Shortage cost effects. In addition, by each detail the transportation industries, packages and other transport and road transport is influenced greatly from ICT. On the other hand, rail and water transport are relatively lower impact by ICT, However, the effects of rail and water transport by ICT is grater than investment ratio of ICT. As a result, increasing investment in the ICT services could contribute to development of rail and water transport development.