• Journal of Conservation Science
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• v.37 no.6
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• pp.689-700
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• 2021

This study aims to optimize the measurement conditions of handmade Hanji paper to reduce the time required for measurement while meeting folding endurance standards, for various basis weights. Thirteen types were selected, including 12 types of Hanji with grammages of 17 g/m², 30 g/m², and 45 g/m², and one type of 75 g/m² copy paper, and 24 sheets were prepared in the laid and chain directions. Subsequently, folding endurance experiments at different load (14.72 N, 9.81 N, 4.91 N) and specimen width conditions (15 mm, 10 mm, 5 mm) were performed, using a 4-MIT folding endurance tester. The results showed that, for specimen widths of 15 mm and 10 mm under a load of 4.91 N, the folding endurance falls within the reference range (10~10000 times). In particular, reduced folding endurance range and measurement time were observed at a width of 10 mm under a load of 4.91 N. Moreover, the endurance trend lines based on the average values of load and specimen width ranges enabled the prediction of the folding endurance within those ranges, according to the decreasing slope. Furthermore, for a specimen width of 15 mm under a load of 4.91 N, the folding endurance in the comparison group (35 to 17723 times) significantly exceeds the upper limit of the reference range (10~10000 times). Therefore, the measurement conditions of 4.91 N with a specimen width of 10 mm are proposed.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.11
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• pp.437-444
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• 2017

Electric Pole is a supporting beam used for power transmission/distribution which is sensitive to external force change of environmental factors. Therefore, power facilities have many difficulties in terms of maintenance/conservation from external environmental changes and natural disasters that cause a great economic impact. The aerial wire cause elasticity due to the influence of temperature, or factors such as wind speed and wind direction, that weakens the electric pole. The situation may lead to many safety risk in day-to-day life. But, the safety assessment of the pole is carried out at the design stage, and aftermath is not considered. For the safety and maintenance purposes, it is very important to analyze the influence of weather factors on external forces periodically. In this paper, we analyze the acceleration data of the sensor nodes installed in electric pole for maintenance/safety purpose and use Kalman filter as noise compensation method. Fast Fourier Transform (FFT) is performed to analyze the influence of each meteorological factor, along with the meteorological factors on frequency components. The result of the analysis shows that the temperature, humidity, solar radiation, hour of daylight, air pressure, wind direction and wind speed were influential factors. In this paper, the influences of meteorological factors on frequency components are different, and it is thought that it can be an important factor in achieving the purpose of safety and maintenance.

• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.1-6
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• 2020

This study was conducted to investigate the effect of different pre-sowing treatments of seeds on germination and growth performance of native threatened tree species Quercus gomeziana A. Camus at the nursery of Chittagong University, Bangladesh. Furthermore, seedling growth attributes under different doses of fertilizer (urea) was also experimented to find the best dose of fertilizer on this tree species at the nursery stage for better field level growth. Seeds were placed to six pre-sowing treatments e.g. control (PT₀), treated with sand paper rubbing (PT₁), nicking (PT₂), seeds immersed in cold water for 48 hours (PT₃), seeds immersed in cold water for 7 days (PT₄) and seeds sown at propagator house with increased temperature (PT₅). It was found from the study that germination was started earlier (at 31 days) in treatments sand paper rubbing (PT₁) and nicking (PT₂). The highest germination percentage (93%) was in PT₁ followed by 86% in seeds immersed in cold water for 7 days (PT₄) and 80% in PT₀ (control). Germination percentage was observed least (63%) in PT₂ even though germination started earlier. For fertilizer dose experiment to seedlings at the nursery level, treatment FT₁: 100 kg/ha (0.33679 g urea/pot/seedling) comparing with other treatments FT₀: 0 kg/ha (Control), FT₂: 200 kg/ha (0.67358 g urea/pot/seedling), FT₃: 300 kg/ha (1.01037 g urea/pot/seedling) showed better performance in case of collar diameter (6.74 mm), number of leaves, shoot dry weight (19.74), total dry weight (28.16 g), total fresh weight (67.96 g), volume index (3904.82), sturdiness (127.69). Finally, it can be concluded that Quercus gomeziana seedlings revealed better performances under the treatment FT₁ in growth and biomass production. Findings of this study will be helpful to take decision on organic fertilizer dose application to seedlings of Q. gomeziana for large scale plantation and conservation of this species.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.412-425
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• 2012

Concrete Soil Erosion Control Dam, which blocks flow of debris flow in torrential stream, are reported to lose expected functions due to structural failure and collapses, caused by poor construction, material deterioration and external impacts. In this paper, an integrity assessment technique for debris barriers was proposed, which allows preliminary detection of problems inherent in debris barriers. The proposed integrity assessment technique is a non-destructive method based on SASW method, one of surface-wave tests. In this paper, a practical procedure and analysis guidelines in applying the SASW technique to debris barrier was proposed and its validity was verified using five decrepit debris barriers older than 20-year old. As a result, the SASW method was validated for the reliable grade evaluation method for concrete soil erosion control dam, and the resulting grades turned out to agree with the results determined by Sabang Associations.

• Fire Science and Engineering
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• v.22 no.1
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• pp.99-104
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• 2008

It is important to understand thermal characteristic as a method to estimate the new materials, because spontaneous ignition characterized by causing combustion in the low temperature without ignition source. If can not find out the thermal characteristics of materials, it is frequent that causes of fires could not be found. The danger level of spontaneous ignition material should be estimated and by closely studying its thermal characteristic. However, RPF(Refuse Paper & Plastic Fuel) is a solid matter and getting increasesa year by year because it is an economy profit as alternative energy for limited fossil fuels. Some time RPF occur a fire in the cases of its production process and conservation. Therefore study for thermal stability and critical ignition temperature of RPF was so imperative that the experiment by means of Bombe Calorimeter, TG-DTA, MS80, SIT-II, and Wire Basket Test was implemented. As a result, RPF had a caloric value 26.4-28.3 MJ/kg, and its initial pyrolysis temperature was $192^{\circ}C$ at heating rate 2 K/min. With the result of analysis by MS 80 which is an instrument measuring microscopic calory, pure RPF not containing water has higher caloric value than RPF containing 20% water. Also, SIT-II which is an instrument of insulated auto-ignition was ignited by $118.5^{\circ}C$. This temperature is lower than that of Wire Basket Test. The critical ignition temperature was calculated by Frank-Kamenetskii equation can cause ignition at $80^{\circ}C$ when conserved in the height of 10 m by the standard of infinity slab.

• Environmental and Resource Economics Review
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• v.16 no.3
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• pp.485-510
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• 2007

The purpose of this paper is to empirically analyze the economic effect of energy saving investment on the improvement of energy intensity. The data used in this paper are panel data, both time-series and cross-section data. In addition, eight manufacturing sectors has been divided into two groups: massive energy consuming (four industries) and non-massive energy consuming (four industries) ones and the time period of analysis is from 1982 to 2004. According to the empirical results, firstly, energy saving investment has a negative relationship with energy intensity, however, its effect is not high in terms of absolute volume of energy consuming. Secondly, in improving energy intensity of energy saving investment, its elasticity IS higher in non-massive energy consuming sector compared it with massive energy consuming sector. Thirdly, automation investment is also playing an important role in energy conservation. The elasticities of automation investment to energy intensity are larger than those of energy saving investment. In terms of the reduction of greenhouse gas per investment unit cost, however, energy saving investment has larger effect than automation investment.

• Journal of Energy Engineering
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• v.17 no.4
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• pp.182-188
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• 2008

This paper is to compare the carbon-balanced and liner air-fuel ratio determination methods for alternative fuels. In the previous work, expansion of Eltinge chart, unburned hydrocarbon compensation, comparison of the results from various methods were discussed. It has been also concluded that Eltinge method might be regarded as the most general equation of AFR determination among the existing ones. In the recent years, however, increasing demand for the environmental preservation, including global warming-up protection, and energy conservation lead to introduce the alternative fuel to the internal combustion engine. Therefore, the exact calculations of AFR for these fuels are needed. Especially, for the fuel that contains oxygen, all AFR calculation equations except Eltinge have to be re-formulated. In this paper, the AFR for alternative fuel were calculated by re-formulated carbon balance, accuracy of which was already confirmed, and linear equations, which are newly proposed by statistical method for each fuel. The results show that AFRs based on carbon balance have a little more error compared with gasoline, however, the accuracy is enough for this formula to apply to various fuel. The proposed linear equation also have excellent accuracy below $\lambda=1.2$.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.1
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• pp.80-89
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• 2011

In this paper, a new real time video scaling technique which preserved the contents of a movie was proposed. Because in a movie a correlation exists between consecutive frames, in this paper by determining the seam of the current frame considering the seam of the previous frame, it was proposed the real time video scaling technique without the shaking phenomenon of the contents even though the entire video is not analyzed. For this purpose, frames which have similar features in a movie are classified into a scene, and the first frame of a scene is resized by the seam carving at the static images so that it can preserve the contents of the image to the utmost. At this time, the information about the seam extracted to convert the image size is saved, and the sizes of the next frames are controlled with reference to the seam information stored in the previous frame by each frame. The proposed algorithm has the fast processing speed of the extent of being similar to a bilinear method and preserves the main content of an image to the utmost at the same time. Also because the memory usage is remarkably small compared with the existing seam carving method, the proposed algorithm is usable in the mobile terminal in which there are many memory restrictions. Computer simulation results indicate that the proposed technique provides better objective performance and subjective image quality about the real time processing and shaking phenomenon removal and contents conservation than conventional algorithms.

• Korean Journal of Heritage: History & Science
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• v.44 no.4
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• pp.130-141
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• 2011

This paper examined the bleaching effect of the two types of gel made with neutralizing agent such as sodium meta silicate gel & triethylamine gel mixed with carbopol resin 940 & 934 which has thickness effect in broad pH region and mixed with 10% hydrogen peroxide. Sodium meta silicate gel(1.6g included) provided pH 10, the most suitable environment for bleaching. The result of comparison of the baseline colour changes(${\Delta}E*ab$) and colour changes according to time(${\Delta}E*ab$) is as following. Group1(carbopol 940, sodium meta silicate, Urea Hydrogen Peroxide) showed 112% efficiency at CS-2; 63.3% at CS-4; 87.4% at CS-6. Group2(carbopol 934, sodium meta silicate, Urea Hydrogen Peroxide) showed 77.3%, 67.3%, 109.6% at CS-8, CS-10, CS-12 respectively; CT-1, CT-3, CT-5 of Group3(carbopol 940, triethylamine, Urea Hydrogen Peroxide) showed 36.8%, 73.2%, 74%; In Group4(carbopol 934, triethylamine, Urea Hydrogen Peroxide), efficiency of CT-6, CT-8, and CT-10 was 81.7%, 95.4%, and 95.7%. The paper showed that various concentration of neutralizing agent such as sodium meta silicate and triethylamine have bleaching effect. Viscosity of the gel including sodium meta silicate was higher than the gel including triethylamine. High viscosity helps the bleaching gel sit on the smooth slope of the ceramics. As a result, sodium meta silicate is considered to provide thickening and bleaching effect required in producing 10% hydrogen peroxide gel.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.561-580
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• 2021

This study analyses the historical and cultural streets at Pinggang Road in the city of Suzhou, by understanding the development and conservation of the area, and uses the following ways to investigate its development, re-organization, and current state. This paper comprehensively compares, collates and investigates 4 different historical and cultural areas in Insadong and Samcheong-dong in South Korea, and South Luogu Lane in China. From initial research and analysis, this paper gathers the cultural, economic, and societal perspectives as non-physical measures, and spatial structure, road structure, and building maintenance as physical factor framework. It is significant in that it can provide an evaluation model for the preservation and regeneration of historical and cultural streets by presenting the viewpoint of complex development of non-physical and physical elements in Pyeonggang-ro. In addition, it is necessary to conduct optimization and specific research on insufficient areas, such as maintenance and development of programs and signature systems for visitors, and continuous development of historical and cultural network platforms by combining on-site surveys. Basic data should be provided for reference on the street.