• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.3
• /
• pp.624-629
• /
• 2018

The current study was conducted to develop a portable composite gas detector allowing the detection of both $CO_2$ and $CH_4$ gases by means of the Non Dispersive Infra-Red (NDIR) method. The gas detector is configured to radiate infrared waves using infrared lamps, where the wavelength of the infrared light is reduced due to absorption throughout the chamber, and this reduction (absorption) is detected by the absorption detector, before being converted and amplified to a 3.5V~6V electrical signal, providing as accurate a measurement as possible. The conventional singe sensor method measures the relative measurement by absorbing only specified wavelengths of infrared radiation, which in the case of gas detection leads to problems with accuracy due to the lack of a reference sensor when detecting light with a wavelength of only $4.26{\mu}m$. The dual sensor employed in this study provides a comparative measurement between the reference value derived from the wavelength of $3.91{\mu}m$, which is not influenced by other gas sources, and the measurement value derived from the wavelength of $4.26{\mu}m$, in order to reduce the errors and enhance the reliability, thereby allowing low power consumption for portable devices and multi-gas detection for both $CO_2$ and $CH_4$ gases. The portable composite gas detector developed herein provides a measurement rage of 0ppm~5,000ppm for $CO_2$ gas, and 0.5%vol for $CH_4$, which allows the determination of whether the $CO_2$ and $CH_4$ contents in indoor air are less than 1,000ppm or not. The current study established that the composite gas detector can be interlinked with firefighting appliances through portable devices or home automation, and is anticipated to be very effective in fire prevention.

• The KIPS Transactions:PartD
• /
• v.10D no.3
• /
• pp.459-470
• /
• 2003

It is required to research on high-dimensional index structures for efficiently retrieving high-dimensional data because an attribute vector in data warehousing and a feature vector in multimedia database have a characteristic of high-dimensional data. For this, many high-dimensional index structures have been proposed, but they have so called ‘dimensional curse’ problem that retrieval performance is extremely decreased as the dimensionality is increased. To solve the problem, the cell-based filtering (CBF) scheme has been proposed. But the CBF scheme show a linear decreasing on performance as the dimensionality. To cope with the problem, it is necessary to make use of parallel processing techniques. In this paper, we propose a parallel CBF scheme which uses a horizontally-partitioned technique as declustering. In order to maximize the retrieval performance of the proposed parallel CBF scheme, we construct our parallel CBF scheme under a SN (Shared Nothing) cluster architecture. In addition, we present a data insertion algorithm, a rage query processing one, and a k-NN query processing one which are suitable for the SN cluster architecture. Finally, we show that our parallel CBF scheme achieves better retrieval performance in proportion to the number of servers in the SN cluster architecture, compared with the conventional CBF scheme.

• Journal of Korean Society of Steel Construction
• /
• v.20 no.3
• /
• pp.399-407
• /
• 2008

The clamping of torque shear bolt is based on KS B 2819. It was misunderstood that the tension force of the TS bolt was induced generally at the break of pin-tail specified. However, the clamping forces on slip critical connections do not often meet the intended tension, as it considerably varies due to torque coefficient dependent on temperature variables despite the break of the pin tail. In this study, the tension of torque shear bolts were compared with two types of high-strength hexagon bolts by temperature parameters from ${-10^{\circ}C}$ to ${50^{\circ}C}$. Torque shear bolts showed that the average clamping force increased to 20kN as the temperature increased. In case of galvanized high-strength hexagon bolts, the average clamping forces at $0^{\circ}C$, $20^{\circ}C$, $50^{\circ}C$ were recorded over standard bolt tension, 178kN, and the worst standard deviation was 50kN. In case of high-strength hexagon bolts, ave rage clamping forces increased as the temperature went up, and the worst standard deviation was 33kN lower than that of galvanized high-strength hexagon bolts. As for the turn-of-the-nut method, at nut rotation of ${90^{\circ}}$, two types of high-strength hexagon bolts did not met the intended design bolt in tension, 162kN.it is neccessary to re-evaluate the range of turn of nut, ${120^{\circ}{\pm}30^{\circ}}$.

• Journal of Korean Society of Environmental Engineers
• /
• v.34 no.4
• /
• pp.280-287
• /
• 2012

The sources of greenhouse gases (GHG) at Hanyang University Ansan campus, including direct sources, indirect sources, and others, were investigated in order to establish the GHG inventory. Emission of GHG was calculated with the energy use from each source from 2007 and 2009. The indirect emission (56.7%) due to the electricity significantly contributed to total GHG emission. The scenario for the GHG reduction was designed for both campus administration and members. The reduction potential of GHG was simulated from 2007 to 2020 using Long-range Energy Alternatives Planning (LEAP) model. In case of GHG reduction scenario by campus administration, the GHG can be reduced by 63.34 ton $CO_{2eq}/yr$ for stationary combustion in the direct source, by 221.1 ton $CO_{2eq}/yr$ for mobile combustion in the direct source, and by 4,637.34 ton $CO_{2eq}/yr$ for lighting in the indirect source, compared to 2020 Business As Usual (BAU). In case of GHG reduction action scenario by campus members, the reduction potential of GHG was 1293.76 ton $CO_{2eq}/yr$. Overall, the total GHG emissions in 2020 by the both scenarios can be decreased by 24% compared to 2020 BAU.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.7 no.1
• /
• pp.25-31
• /
• 2009

An analytical method of $^{99}Tc$ concentration in soil was set up and discussed considering the $^{99}Tc$ concentration in Korean soil measured with its analytical method. A selective TEVA resin was used to separate and purify the $^{99}Tc$ in the soil sample. $^{99m}Tc$ from a commercial $^{99}Mo/^{99m}Tc$ generator was used as a yield tracer for the chemical separation of $^{99}Tc$ and its problem when using $^{99m}Tc$ as a tracer was discussed. The chemical recovery yield of $^{99}Tc$ was above 70%. The optimum conditions of inductively coupled plasma mass spectrometry system(ICP-MS) were set up to determine the $^{99}Tc$ after the separation process. The minimum detectable activity(MDA) was 15 mBq/kg-dry in this analytical procedure. The $^{99}Tc$ concentration in soils of Jeju and Kori were measured in the rage of 33.73-89.16 mBq/kg-dry. Those values were less than those reported in other countries and seemed to be originated from atmospheric fallout.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.31 no.4
• /
• pp.96-110
• /
• 1989

To suggest the fundamental data for the estimation of crop evaportranspiration by the ca- lculated coefficients for estimating the radiation suitable to the different regions of korea in application of Penman equcation, the daily data such as sc(skycover), n(actual sunshine hours), N(possible sunshine hours), Rs(horizontal solar radiation) and Ra(extraterrestial solar radiation) for 10 years (from 1977 to 1986) collected from 19 meteorological stations were analysed. The results are summarized as follows : 1. The coefficients a, b and c for estimating the radiation taken by the regression method with the daily and monthly mean data of the skycover and the ratio of Rs to Ra were shown as a=0.619, b= -0.0202, c= -0.0023 and a=0.64, b=0.0377 c=0.0001 in ave- rage respectively. 2. The coefficients a and b for estimating the radiation analysed by the regression and arithmetic method from the daily ratio of sunshine hours and Rs to Ra were shown as a= 0.157, b= 0.529, and a=0.119, b= 0.726 in average, respectively. 3. The coefficients a and b for estimating the radiation calculated by the regression me- thod based on the monthly ratio of sunshine hours and radiation were shown as a=0. 319 and b= 0.557 in average. 4. The values of a and b for estimating the radiation taken from the relationship between the daily ratio of sunshine hours and radiation showed high significance level. 5. The standard deviation and the coefficient of variance between the radiation calculated from the coefficients by the regression and arithmetic method with the daily data and the actual radiation were analysed and compared to the results by the coefficients of the modified Penman method (a=0.18, b=0.55) and by those of the F.A.O inodified Penman method(a=0.25, b=0.5). The standard deviation and the coefficient of varia- nce by the regression method in this study showed the lowest value. 6. From the above results, it is suggested that regression method using the coefficients taken from the relationship between the ratio of sunshine hours and the ratio of radia- tion based on the daily data has the highest accuracy in estimating the radiation. 7. The average reference crop evapotranspiration estimating by the modified Penman me- thod using the coefficients a and b derived by the regression method from the daily meterological data was closer to the actual evapotsranspiration of grass measured in Suwon area than the estimated evapotranspiration by the modified Penman method and the F.A.O modified Penman method.

• Cartoon and Animation Studies
• /
• s.17
• /
• pp.21-35
• /
• 2009

Continuous provocation of Japanese government to a Dokdo issue and Agreement on Fisheries between the Republic of Korea and Japan evokes a rage and resistance to whole nation in South Korea. In view of mass culture, Japanese Rightists cartoonists, Kobayashi Yoshinori and Yamano Syarin show distorted history in their works. Therefore the consideration of the birth of the Japanese right-wing cartoon is needed in historical, social and cultural viewpoints. First, the actual condition and historical background of Japanese Rightist will be showed. Second, a new Japanese history textbook which was written by right-wing organizations and Yasukuni-jinja will be discussed objectively. Finally, the representative of Japanese right-wing cartoons, and by Kobayashi Yoshinori and Yamano Syarin about historical distortion will be analyzed carefully. In this dissertation, through the factual analysis of cartoons, in opposition to a prejudice and distortion about Korean history of Japanese Rightist, cartoonists' precise and academic posture is proposed.

• Journal of Life Science
• /
• v.27 no.6
• /
• pp.611-616
• /
• 2017

The antibacterial activities of nine oriental herbal medicine extracts were measured against seven kinds of bacteria known to cause food poisoning and disease. The extracts were prepared with distilled water using an autoclave ($121^{\circ}C$ for 30 min). The extraction yields of nine oriental herbal medicines were in the rage of 0.5%-33.4%. The antibacterial activities were evaluated using the paper-disc method. Extracts of Hwangryeon, Jiyu, and Ohbaeja showed antibacterial activities while the others did not. Extracts of Coptis japonica, Hwangryeon, and Sanguisorba officinalis, Jiyu showed antibacterial activities only against Clostridium perfringens and Listeria monocytogenes. Extracts of Rhus javanica, Ohbaeja showed the strongest antibacterial activities against all the bacteria tested. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of R. javanica extracts were in the range of 2.4~20 mg/ml for the bacteria tested. In conclusion, the extract of R. javanica showed superior antibacterial activities against the seven bacterial strains tested. The MIC and MBC values for each bacterium were represented as strain names (MIC, MBC), which were Bacillus cereus (11.2, 20), Clostridium perfringens (2.4, 4.7), Escherichia coli (9.1, 9.1), Listeria monocytogenes (11.1, 20), Salmonella typhi (4.7, 9.1), Staphylococcus aureus (2.4, 4.7), and Vibrio parahaemolyticus (2.4, 5.3). Further purification and study of this antibacterial material would be helpful for developing antibiotics or promoting synergistic effects with known antibiotics, producing antibacterial material for lengthening the shelf-life of food, and so on.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.368-368
• /
• 2017

Rice is the world's three major crops that is the staple food of Asian. Japonica type rice is consumed in Korea. Rice cultivation area decreases steadily. That is affected by decrease of the farm income with the inventory of 1.7 million tons, which is 2 to 3 times more than the optimal amount due to the decrease in the consumption of rice per person and cultivate high yield varieties. In recent years, as income level has improved, interest in health has been high and consumption for health food has been steadily increasing. For health food, rice is added by adding grains such as millet, sorghum, oats, beans and colored rice rather than white rice. In 1997, RDA(Rural Development Administration) developed black rice 'Heuknambyeo', and then 20 varieties were bred until 2017. In CBARES(Chungbuk Agricultural Research and Extension Services), we have developed new rice varieties 'Cheongpungheukchal' in 2010, 'Cheongpungheukhyangchal' in 2014, 'Cheongpungheukchal' is high in farming preference because of high yield. Black rice has high content of GABA and water-soluble phenol, DPPH radical scavenging activity, and consumers are interested in the function in the body. Therefore, functional and antioxidant activities(anthocyanin, total polyphenol, ${\alpha}-glucosidase$ inhibition) and antioxidant activities(ABTs, DPPH) were analyzed by comparing white and black rice. Testing varieties are 'Chucheongbyeo', best quality cultivars 'Daebo' and 'Samgwang' as white rice which are cultivated much in Chungbuk area, and black rice are 10 varieties including 'Cheongpungheukchal', 'Cheongpungheukhyangchal', 'Josaengheukchal' and so on. It has transplanted on 25th May, at CBARES research paddy by 100% fertilizer recommendation rate. Harvesting time was 50 days after heading by varieties, and has researched growth properties, yield and yield components, functional and antioxidant activities. Anthocyanin content was not measured because there was no pigmented in white rice, the highest value of anthocyanin content was 'Shintoheukmi' and in the range of 125.6~249.6mg/100g by black rice varieties. Total polyphenol content was high 'Cheongpungheukchal' and 'Shintoheukmi' and in the range of 96.68~244.34 mg/100g in black rice, white rice lower than blackish rice at 19.84~22.51mg/100g. ${\alpha}-glucosidase$ inhibition was high 'Cheongpungheukchal', 'Cheongpungheukhyangchal' and 'Shintoheukmi' in the rage of 75.87~98.85% by black rice varieties, especially 'Samgwang' was 80.75% and the other white rice was higher than 58~68%.

• Applied Chemistry for Engineering
• /
• v.29 no.4
• /
• pp.376-381
• /
• 2018

The purpose of this study is to investigate and optimize an effectiveness process for the recovery of Pd from the spent Pd/C catalyst by the process of hydrogenation of maleic anhydride over Pd/C. Pd solution recovered from Pd/C catalyst was used to prepare Pd/C catalysts. Their characteristics were compared to those of Pd/C catalyst prepared by using a reagent grade precursor solution. Pd in the spent catalyst was leached by the modified process with dry and wet methods to obtain the high recovery ratio of Pd. The burn-out of carbon in the spent Pd/C catalyst was carried out in the rage of $600-900^{\circ}C$. Pd content of carbonized catalyst was confirmed by XRF and ICP. Pd was extracted from carbonized spent catalysts with acid solutions of 1,2 and 4 M HCl at a leaching temperature of $90^{\circ}C$ for 2 h. The high recovery ratio of Pd was shown as 92.4% that leached in 4 M HCl. Also Pd/C catalysts were prepared by using the leached solution and the reagent grade of $H_2PdCl_4$ as a precursor solution and the characteristics were analyzed by XRD, CO-chemisorption and FE-TEM. As a result, the dispersion of the catalyst prepared by using the leached solution was 34.6%, which was found to be equal to or more than that of the Pd/C catalyst prepared by the reagent grade precursor solution.