• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.4
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• pp.359-370
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• 2022

Objective: This study is intended to design a commercially available passive sampler and conduct performance test on its use as a media for evaluating a working environment. Methods: This study was conducted to select adsorbents, design models, and evaluate storage stability and sampling rates for the development of new types of passive samplers. Results: The impurity detection, adsorbent capacity and breakthrough volume of five types of activated carbon were tested for selection of an adsorbent. One product was selected in consideration of the efficiency of purchase. A number of passive samplers were designed in a radial style and a badge style using plastic as a material. The final two prototypes were made using molds or 3D printing. For the storage stability evaluation, samples were stored at different temperature for 1~21 days and then analyzed. Most of the chemicals had excellent storage stability when refrigerated. However, some chemicals such as dichloromethane and methyl ethyl ketone need to be analyzed as soon as possible after sampling. Conclusion: In this study, new types of passive samplers for 66 chemical compounds were developed. The evaluation of storage stability and sampling rates showed different results depending on the properties of the chemical substance. For some chemicals such as methyl ethyl ketone and dimethylformamide, activated carbon is inappropriate as an absorbent. In future studies, additional experiments are required on chemicals that are difficult to collect with activated carbon.

• Korean Security Journal
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• no.24
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• pp.91-123
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• 2010

The threat factors available for occurrence given G20 Summit Meeting are expected leader terrorism, hostage terrorism, bomb terrorism, public facilities terrorism, and aircraft terrorism. As for the threat groups, which are expected in Korea, the North Korea, Islam extremist group, and the group such as NGO organization of being opposed to international meeting are regarded as having possibility of causing hazard. Thus, the purpose of this study is to suggest VIP Security-measure plans in the main site in preparation for G20 Summit Meeting. Accordingly, each country in the world is adopting 'the principle of Triple Ring' in common. Thus, it elicited a coping plan by 1st line(inner ring) 2nd line(middle ring) 3rd line(outer ring) based on this principle, and proposed even an opinion together that will need to be reflected in light of policy for the VIP security measures. In conclusion, as for the VIP Security-measure plans in the main site in preparation for G20 Summit Meeting, In the inner ring(safety sector), first, an intercepting measure needs to be devised for a spot of getting into and out of vehicles given the Straight Street. Second, the Walking Formation needs to be reinforced boldly in the exposed area. In the middle ring(security sector), first, the control plan needs to be devised by considering particularity of the main site. Second, there is necessity for adopting the efficient security badge operation plan that is included RFID function within security badge. In the outer ring(aid protective sector), first, there is necessity of preparing for several VIP terrorisms, of collecting information and intelligence, and of reinforcing the information collection system against terrorism under the cooperation with the overseas information agency. Second, the urgent measure training in time of emergency needs to be carried out toward security agent event manpower. Third, to maintain the certain pace in VIP motorcade, the efficient traffic control system needs to be operated. Finally, as for what will need to be reflected in light of policy for VIP security measures, first, there is necessity for allowing VIP residence to be efficiently dispersed to be distributed and controlled. Second, there is necessity for allowing impure element to misjudge or attack to be failed by utilizing diverse deception operations. Third, according to the reorganization in North Korea's Organization of the South Directed Operations, the powerful 'military-support measure' needs to be driven from this G20 Summit Meeting. For this, the necessity was proposed for further reinforcing the front back defense posture under the supervision of the Ministry of National Defense and for positively coping even with detecting and removing poison in preparation for CBR (chemical, biological, and radio-logical) terrorism.

• The Journal of Korean Society for Radiation Therapy
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• v.24 no.2
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• pp.107-114
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• 2012

Purpose: Unlike the existing linear accelerator with photon, proton therapy produces a number of second radiation due to the kinds of nuclide including neutron that is produced from the interaction with matter, and more attention must be paid on the exposure level of radiation workers for this reason. Therefore, thermoluminescence dosimeter (TLD) that is being widely used to measure radiation was utilized to analyze the exposure level of the radiation workers and propose a basic data about the radiation exposure level during the proton therapy. Materials and Methods: The subjects were radiation workers who worked at the proton therapy center of National Cancer Center and TLD Badge was used to compare the measured data of exposure level. In order to check the dispersion of exposure dose on body parts from the second radiation coming out surrounding the beam line of proton, TLD (width and length: 3 mm each) was attached to on the body spots (lateral canthi, neck, nipples, umbilicus, back, wrists) and retained them for 8 working hours, and the average data was obtained after measuring them for 80 hours. Moreover, in order to look into the dispersion of spatial exposure in the treatment room, TLD was attached on the snout, PPS (Patient Positioning System), Pendant, block closet, DIPS (Digital Image Positioning System), Console, doors and measured its exposure dose level during the working hours per day. Results: As a result of measuring exposure level of TLD Badge of radiation workers, quarterly average was 0.174 mSv, yearly average was 0.543 mSv, and after measuring the exposure level of body spots, it showed that the highest exposed body spot was neck and the lowest exposed body spot was back (the middle point of a line connecting both scapula superior angles). Investigation into the spatial exposure according to the workers' movement revealed that the exposure level was highest near the snout and as the distance becomes distant, it went lower. Conclusion: Even a small amount of exposure will eventually increase cumulative dose and exposure dose on a specific body part can bring health risks if one works in a same location for a long period. Therefore, radiation workers must thoroughly manage exposure dose and try their best to minimize it according to ALARA (As Low As Reasonably Achievable) as the International Commission on Radiological Protection (ICRP) recommends.

• Korean Journal of Heritage: History & Science
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• v.53 no.3
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• pp.142-163
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• 2020

In the early Joseon dynasty, the meritorious vassals' portrait of Jeokgae (1467, 1476), Jeongguk (1506)·Jeongnan (1507), and Wisa (1545) were defined as the 2^nd period of the official uniform, in which the acheongsaek HeukDanryung appeared and settled. A total of seven portraits were analyzed, including three portraits of Jeokgae (1467, portrait production 1476) Son-so, Oh Jachi, and Jang Malson, and four portraits of Jeongguk (1506)·Jeongnan (1507) Yoo Sunjung, Hong Gyeongju, Lee Woo, and Yoo Hong. In the portrait of the Jeokgae wearing a Yebok HeukDanryung, in the case of the Samo, the height of the Samo, which had been raised at the beginning of King Seongjong, was lowered again, and the parietal part was rounded. The pattern was not expressed on the wide oval side wings of the Samo. In addition, the pattern was not expressed on the acheongsaek Danryung, Dapho, and Cheolrik. The colors of Dapho and Cheolrik were unified in green and red, respectively. The Mu of Danryung and Dapho was expressed as 'in and out wrinkled Mu', and the shoes were expressed in Baekhwa. Another feature is that the Jeokgae's portrait is expressed not as the Pumgye at the time of appointment, but as the Pumgye of the portrait production time. In the portrait of the Jeongguk·Jeongnan wearing a Sibok HeukDanryung, the height of the Samo lowered from the Jeokgae was maintained, while the parietal part was slightly narrowed and bent forward. The side wings of the Samo were expressed as an oval with a uniform width, and still the pattern was not expressed on the side wings. The pattern was not expressed in the costume of the Danghagwan's portrait, but the cloud pattern began to be expressed in the costume of the Dangsanggwan's portrait. And the Danryung was expressed as single Danryung without lining. In the portrait of Dangsang, the red Dapho and green Cheolrik were expressed, and in the portrait of Dangha, the green Dapho and blue Cheolrik were expressed. Therefore, it was found that the color of the undergarment was distinguished according to the Dangsang and Dangha. In Danryung and Dapho, the 'in and out wrinkled Mu' were maintained. The shoes were expressed in Heukhwa, and the rank badge and rank belt reflect the Pumgye at the time of the appointment. On the other hand, the portrait of Wisa could not be confirmed, but through the recording painting of the reign of King Meongjong, it was found that it was similar to the Danryung system of the reign of King Jungjong. Through the 2^nd period of the meritorious vassal's portrait of Jeokgae, it was confirmed that the HeukDanryung outfit began to be used as the official uniform of the meritorious vassal's portrait, and that the Pumgye of the portrait production time was reflected in the portrait. After the meritorious vassal's portrait of Jeongguk, the pattern began to be expressed in the costumes, and in particular, it was possible to distinguish Dasang and Dangha by the presence or absence of the HeukDanryung's pattern. In addition, it was confirmed that the expressed aspect of the official uniform was consistent with the practices and regulations at the time.

• Journal of Korean Elementary Science Education
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• v.43 no.2
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• pp.301-321
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• 2024

This study aims to elucidate the historical origins of the long-term demand for the integration of "science subject classes" and "science-related events" within the context of science education for teachers. During the 1970s, science education in elementary schools faced a dual challenge marked by the tension between implementing the third curriculum, which emphasized fundamental science, and the "Pan-National Scientification Movement," which focused on technology education. The Ministry of Education was compelled to integrate the sudden demands of the Yushin regime into the ongoing third curriculum. As these demands emerged from dual policy directives, activities related to elementary science education were subsequently categorized into formal science subject classes and extracurricular science-related events. Although the movement did not directly alter the curriculum, it instigated modifications in personnel structure, activity spaces, and evaluation systems within schools. The introduction of the Pan-National Scientification Movement in elementary schools resulted in changes including the establishment of a new "science lead teacher system," the creation of a dedicated "science corner," and the implementation of a "science badge system." Although the movement was abruptly introduced, it ostensibly contributed to the advancement of the inquiry-oriented approach promoted by the third curriculum. Paradoxically, this advancement was facilitated by the integration of the consequences of the movement into schools' autonomous, extracurricular activities spearheaded by frontline education offices and schools. Although the movement represented a government-driven policy at a particular juncture in time, the manner in which science education practitioners responded to urgent governmental mandates, while preserving the integrity of the long-established third curriculum framework, involved dividing education activities into subject-specific classes and extracurricular science activities. Examining how science education practitioners in the 1970s proactively addressed these challenges offers valuable insights for the science education community in adapting to the current rapidly evolving educational landscape.

• Journal of the Korean Geotechnical Society
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• v.31 no.1
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• pp.37-46
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• 2015

In this study, a blast furnace slag with the alkaliphilic microorganism (Bacillus halodurans) alkaline activator was used to cement natural soils in the field. A low-cost and massive microbial solution for cementation of field soils was produced and compared with existing microbial culture in terms of efficiency. A field soil was prepared for three different cementation areas: a cemented ground with microbial alkaline activator (Microbially-treated soil), a cemented ground with ordinary Portland cement (Cement-treated soil), and untreated ground (Non-treated soil). The testing ground was prepared at a size of 2.6 m in width, 4 m in length, and 0.2 m in depth. After 28 days, a series of unconfined compression tests on the cement-treated and microbially-treated soils were carried out. On the other hand, a torvane test was carried out for non-treated soil. The strength of field soils treated with microorganism was 1/5 times lower than those of cement-treated soil but is 6 times higher than non-treated soil. The pH measured from microbially-treated soil was about 10, which is lower than that of cement-treated soil (pH = 11). Therefore, it is more eco-friendly than Portland cemented soils. The C-S-H hydrates were found in both cement- and microbially-treated soils through SEM-EDS analyses and cement hydrates were also found around soil particles through SEM analysis.

• Journal of Radiation Protection and Research
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• v.21 no.3
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• pp.147-153
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• 1996

The Korea Atomic Energy Research Institute(KAERI) conducted a intercomparison study for personnel dosimetry services in Korea to enhance the accuracy and precision of the dosimetry system. Nine types of dosimeters(6 TLD, 3 film badge) from 7 institutions took part in this intercomparison study. Each participant submitted 30 dosimeters including transit control for irradiations. Both TLDs and film badges were irradiated with Cs-137 gamma, Sr/Y-90 beta and 4 X-ray beams in ISO wide series. Four dosimeters were irradiated on phantom with same dose equivalent for each field category. The delivered dose equivalent was in the range of $0.1{\sim}10mSv$. The participants assessed the results of their dosimeter readings in terms of the ICRU operational quantities for personal monitoring, Hp(10) and Hp(0.07). Most participants except 1 dosimeter estimated the delivered dose equivalent with biases less than ${\pm}25%$ for Cs-137 and Sr/Y-90. But for X-rays, the biases exceeded ${\pm}35%$ in some cases bacause the dose evaluation algorithm was based on the ANSI N13.11 X-ray fields which are different from those given by ISO.

• The Journal of Internal Korean Medicine
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• v.21 no.1
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• pp.65-73
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• 2000

Objectives : The effects of cotreatment of adriamycin and ethanol extract of herb (Palgin-tang hab Hwajuck-hwan a traditional medicine for cancer treatment in oriental medicine) on the induction of apoptotic cell death were investigated in human liver origin cell lines, Chang. Methods : Chang(ATCC) liver cells were cultured in RPMI-1640(Gibco SRL Co, Gaithersburg, MD) badge including 10% fetal bovine serum. Chang liver cells were treated with various concentrations(from 10 to $0.16{\mu}l$) of adriamycin and herb extract(from 500 to $31.25{\mu}l$) After 48h later, the cells were tested for viability by Crystal violet staining assay. Adriamycin and Herb extract induced ladder pattern of DNA fragmentation in Chang cells. Genomic DNA was isolated and separated on 1.5% agarose gels. The DNA was stained with ethidium bromide and visualized under UV light. Results : The death of Chang cells was synergistically induced by the cotreatment of adriamycin and ethanol extract of herb. In addition, the cotreatment-induced cell death of Chang cells was mediated by apoptotic death signal processes. The phosphotransferase activity of JNK1 remained in a basal level in Chang cells which was treated individually with the adriamycin and ethanol extract of herb. However, it was markedly increased in Chang cells which was cotreated with adriamycin and ethanol extract of herb. In addition, the expression of Fas and FasL was markedly induced by the cotreatment of adriamycin and herb extract. For a while, the expression of Sax was a eminently increased by the ethanol extract of herb. However, Scl2 expression was not affected by the individual or cotreatment of adriamycin and herb extract. Conclusions : our results suggest that the cotreatment of adriamycin aM ethanol extract of herb induces synergistic apoptotis of human liver origin Chang cells via the upregulation of JNK, Fas, FasL and Bax.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.4
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• pp.288-295
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• 2013

Nitrogen dioxide ($NO_2$) gas damage on vegetable crops commonly occurs in plastic film houses where relatively large amounts of $NO_3{^-}$ are applied in acid soils. In acid soils, $HNO_2$ can be formed from the $NO_2{^-}$ accumulated during denitrification, and $NO_2$ can be evolved from the chemical self-decomposition of $HNO_2$. In this study, $NO_2$ gas production and its detrimental effects on plants were investigated in soils of various conditions to elucidate the mechanisms involved in the gas production. A silty loam soil was amended with $NO_3{^-}$ (500 mg N $kg^{-1}$) and glucose, and pH and moisture of the soil were adjusted respectively to 5.0 and 34.6% water holding capacity (WHC) with 0.01 M phosphate buffer. The soil was placed in a 0.5-L glass jar with strawberry leaf or $NO_2$ gas absorption badge in air space of the jar, and the jar was incubated at $30^{\circ}C$. After 4-5 days of incubation, dark burning was observed along the outside edge of strawberry leaf and $NO_2$ production was confirmed in the air space of jar. However, when the soil was sterilized, $NO_2$ emission was minimal and any visible damage was not found in strawberry leaf. In the soil where water or $NO_3{^-}$ content was reduced to 17.3% WHC or 250 mg N $kg^{-1}$, $NO_2$ production was greatly reduced and toxicity symptom was not found in strawberry leaf. Also in the soil where glucose was not amended, $NO_2$ production was significantly reduced. In soil with pH of 6.5, $NO_2$ was evolved to the level causing damage to strawberry leaf when the soil conditions were favorable for denitrification. However, compared to the soil of pH 5.0, the $NO_2$ production and its damage to plants were much less serious in pH 6.5. Therefore, the production of $NO_2$ damaging plants might be occurred in acid soils when the conditions are favorable for denitrification.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.1
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• pp.38-47
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• 2016

Objectives: The objective of this study was to determine the exposure levels of forklift operators to diesel engine exhaust(DEE) using black carbon(BC), elemental carbon(EC), and nitrogen dioxide($NO_2$) as indicators. Methods: A total of eight forklift operators in six collection companies were assessed over a period of two months from July to September 2015. BC was measured using a real-time monitor and respirable EC samples were analyzed using the NIOSH method 5040. $NO_2$ samples were collected using a passive badge-type sampler. Results: The geometric mean of BC, EC and $NO_2$ were $3.1-19.1{\mu}g/m^3$, $2.1-23.8{\mu}g/m^3$, and 12.5-166.6 ppb at all companies. When forklifts were operating both outside and inside, BC concentrations increased 2.0-5.6 times. The highest increase was observed when forklifts were operating indoors. The increase in BC concentrations varied by company(company A: 2.0 times, B: 3.2 times, C: 5.6 times, D: 2.1 times, E: 5.1 times, F: 2.6 times). The geometric mean of BC, EC, and $NO_2$ for the forklift operators was $9.6{\mu}g/m^3$, $7.9{\mu}g/m^3$, and 48.9 ppb, respectively. The geometric mean of BC, EC, and $NO_2$ for manufacturing workers was $9.3{\mu}g/m^3$, $0.9{\mu}g/m^3$, and 85.2 ppb, respectively. The mean BC and EC exposure levels for the forklift operators were slightly higher than those for manufacturing workers, but $NO_2$ levels for manufacturing workers were higher than those for the forklift operators(p>0.05). Multiple regression analysis revealed that diesel exhaust emissions standard, forklift weight and forklift manufacturer were the most influential factors in determining worker exposure. Conclusions: In the DEE work environment, workers who perform tasks within the workplace as well as inside forklifts as operators are likely to be exposed to a lack of ventilation. Further study of forklift operators' exposure to DEE indicators should be conducted to include a wider range of occupational and environmental situations, such as collection procedures, seasonal situations, types of fuel used, and number of forklifts.