• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.60-66
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• 2021

Various insects live around us. Nowadays, insects are raised as a hobby at home or medicinal insects are bred in large quantities for commercial purposes. In addition, various studies have been conducted to understand the various growth characteristics of insects. In the laboratory, environmental factors were changed to do that, but only the growth characteristics could be analyzed. However, it is almost not easy to measure the skin temperature or body temperature basically needed to reveal the growth characteristics in the case of insects. In particular, the results of experiments on the skin temperature of winged insects are very insufficient. In this study, the skin temperature of insects was photographed and measured for bees and butterflies living in natural conditions under various biological activity conditions such as at rest and during flight using a thermal imaging camera, a non-contact temperature measurement method. Through quantitative analysis of the experimental results, the relationship between the biological activity characteristics of each insect and the skin temperature resulting from such biological activity was investigated. In addition, it was confirmed that honeybees maintained different skin temperatures for three important activities, such as flying, honey collection, and relocation, and that the butterflies performed a warm-up stage for flight similar to the characteristics of moths.

• Journal of radiological science and technology
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• v.44 no.4
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• pp.359-365
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• 2021

A heavy particle accelerator is a device that accelerates particles using high energy and is used in various fields such as medical and industrial fields as well as research. However, secondary neutrons and particle fragments are generated by the high-energy particle beam, and among them, the neutrons do not have an electric charge and directly interact with the nucleus to cause radiation of the material. Quantitative evaluation of the radioactive material produced in this way is necessary, but there are many difficulties in actual measurement during or after operation. Therefore, this study compared and evaluated the generated radioactive material in the concrete shield for protons and carbon ions of specific energy by using the simulation code FLUKA. For the evaluation of each energy of proton beam and carbon ion, the reliability of the source term was secured within 2% of the relative error with the data of the NASA Space Radiation Laboratory(NSRL), which is an internationally standardized data. In the evaluation, carbon ions exhibited higher neutron flux than protons. Afterwards, in the evaluation of radioactive materials under actual operating conditions for disposal, a large amount of short-lived beta-decay nuclides occurred immediately after the operation was terminated, and in the case of protons with a high beam speed, more radioactive products were generated than carbon ions. At this time, radionuclides of ⁴⁴Sc, ³H and ²²Na were observed at a high rate. In addition, as the cooling time elapsed, the ratio of long-lived nuclides increased. For nonparticulate radionuclides, ³H, ²²Na, and for particulate radionuclides, ⁴⁴Ti, ⁵⁵Fe, ⁶⁰Co, ¹⁵²Eu, and ¹⁵⁴Eu nuclides showed a high ratio. In this study, it is judged that it is possible to use the particle accelerator as basic data for facility maintenance, repair and dismantling through the prediction of radioactive materials in concrete according to the cooling time after operation and termination of operation.

• Journal of Korean Society on Water Environment
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• v.27 no.1
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• pp.19-29
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• 2011

In order to assess the influences of bottom sediment on water quality, following measurement were made. (1) Estimations of pollutant loads from the bottom sediment based on mass balance concept, (2) measurements of pollutant concentrations in the sediment to assess the pollution level and influence potential, (3) in situ and laboratory measurements of Sediment Oxygen Demants (SOD) and pollutant load (sediment release) from bottom sediment. Analyses of inflow and outflow loadings using simple mass balance show that there are some variations found according to the pollutants. However, there is no consistent evidence that the sediment can be a source of pollutants. Pollutant concentrations in the sediment range 16~724.8 mg/kg (COD), 1.68 ~12.64 mg/kg (T-P), 5.6~76.8 mg/kg (T-N), 0.32~21.6 mg/kg ($NH_3$-N), 0.092~0.544 mg/kg ($NO_2$-N), 4.8~18.4 mg/kg ($NO_3$-N), and 1.59~11.23 mg/kg ($PO_4$-P). Measured SOD ranges $0.190{\sim}0.802g{\cdot}m^{-2}{\cdot}d^{-1}$ and measured release rate ranges $-1618.42{\sim}10mg/m^2{\cdot}d$(COD), $-12{\sim}16mg/m^2{\cdot}d$(T-P), $-197.37{\sim}140mg/m^2{\cdot}d$(T-N), $0.4{\sim}74.32mg/m^2{\cdot}d$($NH_3$-N), $-2.04{\sim}0.8mg/m^2{\cdot}d$ ($NO_2$-N), $-70{\sim}40mg/m^2{\cdot}d$ ($NO_3$-N), and $-26.11{\sim}28.55mg/m^2{\cdot}d$($PO_4$-P). All study results indicate that bottom sediments in the Seoha weir show only limited effects on the water quality. It implies that sediment dredging is not an effective option or management measure to reduce pollutant loading.

• Journal of the Korean GEO-environmental Society
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• v.12 no.7
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• pp.5-12
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• 2011

When choosing the support pattern of tunnel, the characteristics of rock are identified from the result of the surface geologic survey, boring, and geophysical prospecting and laboratory test. And a rock mass rating is classified and excavation method and standard support pattern are designed considering rock classification, domestic and international construction practices, numerical analysis. According to the revised design standard for tunnel, it was recommended to classify the rock mass rating for the design of tunnel into a rating based on RMR. If necessary, it proposed a flexible standard allowed applying more atomized the rock mass rating and Q-System. Also, the resonable verification of the support pattern must be accompanied because the factors affecting the structure and behavior of ground during the construction of tunnel are the main factors of uncertainty factors such as the nature of ground, ground water and the characteristics of structural materials. These days, such verification method is getting more specialized and diversified. In this study, the empirical method, numerical analysis and comparative analysis of in situ measurements were used to prove the reasonableness in the support pattern by RMR and Q-value on the Imha Dam emergency spillway.

• Korean Journal of Ecology and Environment
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• v.54 no.1
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• pp.39-48
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• 2021

In order to control algal bloom, which causes environmental problems such as eutrophication in freshwater ecological environments, many attempts have recently been made using biological approaches. Among them is filtration using bivalve. Algae control with filter-feeding bivalves is emerging as an eco-friendly method. In this study, bivalves collected at Baekje weir in Geum River in Korea from Jun to Sep 2020 were tested to find out the possibility of algae control using filter-feeding bivalves through laboratory experiments. The Unio douglasiae, Anodonta woodiana, and Anodonta arcaeformis collected from Baekje weir were put into a water tank (2 L) containing Clorella vulgaris, and as a result, the average filtration rate was 95.9% per animal after 24 hrs. Calculating this with the Chl-a concentration converted to a calibration curve, it was found that the average of 154.84 ㎍ L^-1 of Chl-a was reduced. Based on this calculation, the possibility that one bivalve can eliminate Chl-a in one month is 0.0005%. It is expected that the effect is 20.14% when there are 40,000 animals. These results indirectly showed how effective bivalve's ability to control Chl-a in their habitat is. Although this study was limited to calculating the algae control ability of aquatic ecosystem based on the filtration rate of bivalve and the corresponding Chl-a reduction rate, it is thought that it will be used as basic data for integrated research from various factors and viewpoints (phytoplankton, aquatic plants, benthic organisms, and sediments) through additional research.

• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.75-84
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• 2020

This paper described the analysis result on heaving of soft ground with DCM column type, based on the results of laboratory model tests on the soft ground with DCM column. The heave characteristics of the soft ground were evaluated according to the application of DCM column in soft ground. The results showed that the heaving of soft ground without DCM column occurred rapidly when the lateral deformation of soft ground increased significantly under the 4th load step condition. In addition, the heaving of soft ground in final load step caused tensile failure of the ground surface. The maximum heaving of the soft ground with the DCM column occurred in the final load step, and the heaving quantity decreased in the order of pile, wall, and grid type. Especially, the soft ground with DCM of grid type effectively resisted ground heaving, even if it was extremely failure in the bottom ground of embankment. The results of the maximum heaving according to the measurement point showed that the heaving of the soft ground with DCM of grid type was 3.1% and 1.6% compared to that of the pile and wall type at the location of LVDT-1, and the heaving of the LVDT-2 position was 1.0% and 2.1%, respectively.

• Journal of the Korea Society of Computer and Information
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• v.27 no.7
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• pp.1-7
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• 2022

Recently, as the use of applications such as big data programs and machine learning programs that are driven while generating large amounts of data in the program itself becomes common, the existing main memory alone lacks memory, making it difficult to execute the program quickly. In particular, the need to derive results more quickly has emerged in a situation where it is necessary to analyze whether the entire sequence is genetically altered due to the outbreak of the coronavirus. As a result of measuring performance by applying large-capacity data to a computing system equipped with a self-developed memory pool MOCA host adapter instead of processing large-capacity data from an existing SSD, performance improved by 16% compared to the existing SSD system. In addition, in various other benchmark tests, IO performance was 92.8%, 80.6%, and 32.8% faster than SSD in computing systems equipped with memory pool MOCA host adapters such as SortSampleBam, ApplyBQSR, and GatherBamFiles by task of workflow. When analyzing large amounts of data, such as electrical dielectric pipeline analysis, it is judged that the measurement delay occurring at runtime can be reduced in the computing system equipped with the memory pool MOCA host adapter developed in this research.

• Journal of Food Hygiene and Safety
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• v.37 no.5
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• pp.297-305
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• 2022

Antioxidants are food additives that extend the shelf life of food products by preventing lipid rancidity caused by active oxygen. They can either be naturally-derived or manufactured synthetically via chemical synthesis. In this study, method validation of five synthetic antioxidants, namely butylated hydroxyanisole, butylated hydroxytoluene, tertiary butylhydroquinone, propyl gallate, and disodium ethylenediaminetetraacetic acid, was performed using a high performance liquid chromatography-ultraviolet visible detector, and the method applicability was evaluated by analyzing foods containing antioxidants. The coefficient of determination (R²) average was 0.9997, while the limit of detection and limit of quantification were 0.02-0.53 and 0.07-1.61 mg/kg, respectively. The intra and inter-day accuracies and precisions were 83.2±0.7%-98.7±2.1% and 0.1%-5.7% RSD, respectively. Inter-laboratory validation for accuracy and precision was conducted using the Food Analysis Performance Assessment Scheme quality control material. The results satisfied the guidelines presented by the AOAC International. In addition, the expanded uncertainty was less than 16%, as recommended by CODEX. Consequently, to enhance public health safety, the results of this study can be used as basis data for evaluating the intake of synthetic antioxidants and assessing their risks in Korea.

• Journal of the Korean Society of Radiology
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• v.16 no.7
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• pp.851-856
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• 2022

The purpose of this study is to confirm the effect of reducing the surface dose around the radiation field in breast cancer radiotherapy using the Field-in-Field (FIF) technique. X-ray was exposed from a linear accelerator (Linac) was used for irradiation, and the surface dose was measured with a glass dosimeter. The source-to-surface distance (SSD) was 90 cm, the field size is 10 × 10 cm², and the X-ray energy was 6 MV and 10 MV, respectively. The surface dose of the FIF was compared with the dose measured in the physical wedge (PW) and dynamic wedge (DW). Wedge angles of 15° and 30° were used in the PW and DW, respectively. Surface dose was measured at 1 cm, 3 cm, and 5 cm from the center of the field size, respectively. According to the results, FIF showed lower surface dose compared to PW and DW regardless of the energy of the X-ray beam, wedge angle, and dose measurement point. Since FIF could reduce the radiation dose in periphery of the field size in breast cancer treatment, it is expected to be able to reduce the secondary damage caused by the radiation beam as well as to obtain a uniform dose distribution on the target.

• Journal of Marine Life Science
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• v.7 no.2
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• pp.86-93
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• 2022

The ecotoxicity test method using Undaria pinnatifida spore is challenging to use throughout the year. Since U. pinnatifida female gametophytes can be cultured in the laboratory, they can be used for ecotoxicity testing at any time. Changes in female gametophyte survival rate and relative growth rate in U. pinnatifida exposed to various environmental conditions were analyzed. The female gametophyte of U. pinnatifida was exposed to salinity (5~40 psu), temperature (5~30℃), pH (4~10), and light intensity (0~120 μmol photon m^-2 s^-1). Based on the highest average value, the survival rate of female gametophyte was highest at a temperature of 20℃, salinity 27.5 psu, pH 8, and light intensity 30 μmol photon m^-2 s^-1. And the relative growth rate was highest at a temperature of 15℃, salinity 35 psu, pH 9, and light intensity of 60 μmol photon m^-2 s^-1. As a result of this study, the method using the optimal conditions for the survival rate and relative growth rate is expected to be a practical test method that can complement the current method.