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Calibration of Gauge Rainfall Considering Wind Effect (바람의 영향을 고려한 지상강우의 보정방법 연구)

  • Shin, Hyunseok;Noh, Huiseong;Kim, Yonsoo;Ly, Sidoeun;Kim, Duckhwan;Kim, Hungsoo
    • Journal of Wetlands Research
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    • v.16 no.1
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    • pp.19-32
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    • 2014
  • The purpose of this paper is to obtain reliable rainfall data for runoff simulation and other hydrological analysis by the calibration of gauge rainfall. The calibrated gauge rainfall could be close to the actual value with rainfall on the ground. In order to analyze the wind effect of ground rain gauge, we selected the rain gauge sites with and without a windshield and standard rain gauge data from Chupungryeong weather station installed by standard of WMO. Simple linear regression model and artificial neural networks were used for the calibration of rainfalls, and we verified the reliability of the calibrated rainfalls through the runoff analysis using $Vflo^{TM}$. Rainfall calibrated by linear regression is higher amount of rainfall in 5%~18% than actual rainfall, and the wind remarkably affects the rainfall amount in the range of wind speed of 1.6~3.3m/s. It is hard to apply the linear regression model over 5.5m/s wind speed, because there is an insufficient wind speed data over 5.5m/s and there are also some outliers. On the other hand, rainfall calibrated by neural networks is estimated lower rainfall amount in 10~20% than actual rainfall. The results of the statistical evaluations are that neural networks model is more suitable for relatively big standard deviation and average rainfall. However, the linear regression model shows more suitable for extreme values. For getting more reliable rainfall data, we may need to select the suitable model for rainfall calibration. We expect the reliable hydrologic analysis could be performed by applying the calibration method suggested in this research.

Measurement of Rectal Rodiation dose in the Patients with Uterine Cervix fencer using In Vivo Dosimetry(Diode Detector) (자궁경부암 환자에서 In vivo dosimetry(Diode detector)를 이용할 직장선량의 측정)

  • Kim, Sung-Kee;Kim, Wan-Sun
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.1
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    • pp.29-37
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    • 2004
  • Purpose : A rectum and a bladder should be carefully considered in order to decrease side effects when HDR patient of uterine cervix cancer. Generally speaking, the value of dosimeter at a rectum and a bladder only depends on the value of a planning equipment, while some analyses of the value of dosimetry at rectum with TLD has been reported Or the contrary, it is hardly to find a report with in vivo dosimetry(diode detector). On this thesis, we would like to suggest the following. When a patient of uterine cervix cancer is in therapy, it is helpful to put a diode detector inside of a rectum in order to measure the rectal dose Based upon the result of the dosimetry, the result can be used as basic data at decreasing side effects. Materials and Methods : Six patients of uterine cervix cancer(four with tandem and ovoid, one with cylinder, and the other one with tandem and cylinder) who had been irradiated with HDR. Ir-192 totally 28 times from February 2003 to June 2003. We irradiated twice in the same distant spots with anterior film and lateral film whenever we measured with a diode detector. Then we did planning and compared each film. Results : The result of the measurement 4 patients with a diode detector is the following. The average and deviation from 3 patients with tandem and ovoid were $274.1{\pm}13.4cGy$, from 1 patient with tandem and ovoid were $126.1{\pm}7.2cGy$, from 1 patient with cylinder were $99.7{\pm}7.1cGy$, and from 1 patient with tandem and cylinder were $77.7{\pm}11.5cGy$. Conclusion : It is difficult to predict how the side effect of a rectum since the result of measurement with a diode detector depends on the state of a rectum. According to the result of the study, it is effective to use a TLD or an in vivo dosimetry and measure a rectum in order to consider the side effect. It is very necessary to decrease the amount of irradiation by controlling properly the duration of the irradiation and gauze packing, and by using shield equipments especially when side effects can be expected.

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Evaluation of the Usefulness of the Transmittance of Metal Filaments Fabricated by 3D Printers in Radiation Therapy (방사선 치료에서 3D 프린터로 제작된 금속 필라멘트의 투과율에 관한 유용성 평가)

  • Kwon, Kyung-Tae;Jang, Hui-Min;Yoon, Myeong-Seong
    • Journal of the Korean Society of Radiology
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    • v.15 no.7
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    • pp.965-973
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    • 2021
  • Since radiation therapy is irradiated with high-energy X-rays in a variety of at least 20 Gy to 80 Gy, a high dose is administered to the local area where the tumor is located, and various side effects of some normal tissues are expected. Currently, in clinical practice, lead, a representative material, is used as an effort to shield normal tissues, but lead is classified as a heavy metal harmful to the human body, and a large amount of skin contact can cause poisoning. Therefore, this study intends to manufacture a measurement sheet that can compensate for the limitations of lead using the materials Tungsten, Brass, and Copper of the 3D printer of the FDM (Fused Deposition Modeling) method and to investigate the penetration performance. Tungsten mixed filament transmission measurement sheet size was 70 × 70 mm and thickness 1, 2, 4 mm using a 3D printer, and a linear accelerator (TrueBeam STx, S/N: 1187) was measured by irradiating 100 MU at SSD 100 cm and 5 cm in water using a water phantom, an ion chamber (FC-65G), and an elcetrometer (PTW UNIDOSE), and the permeability was evaluated. As a result of increasing the measurement sheet of each material by 1 mm, in the case of Tungsten sheet at 3.8 to 3.9 cm in 6 MV, the thickness of the lead shielding body was thinner than 6.5 cm, and in case of Tungsten sheet at 4.5 to 4.6 cm in 15 MV. The sheet was thinner than the existing lead shielding body thickness of 7 cm, and equivalent performance was confirmed. Through this study, the transmittance measurement sheet produced using Tungsten alloy filaments confirmed the possibility of transmission shielding in the high energy region. It has been confirmed that the usability as a substitute is also excellent. It is thought that it can be provided as basic data for the production of shielding agents with 3D printing technology in the future.

Numerical Analysis of the Grand Circulation Process of Mang-Bang Beach-Centered on the Shoreline Change from 2017. 4. 26 to 2018. 4. 20 (맹방해빈의 일 년에 걸친 대순환과정 수치해석 - 2017.4.26부터 2018.4.20까지의 해안선 변화를 중심으로)

  • Cho, Young Jin;Kim, In Ho;Cho, Yong Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.3
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    • pp.101-114
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    • 2019
  • In this study, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach, which is suffering from erosion problem. We obtain the basic equation (One Line Model for shoreline) for the numerical simulation by assuming that the amount of shoreline retreat or advance is balanced by the net influx of longshore and cross-shore sediment into the unit discretized shoreline segment. In doing so, the energy flux model for the longshore sediment transport rate is also evoked. For the case of cross sediment transport, the modified Bailard's model (1981) by Cho and Kim (2019) is utilized. At each time step of the numerical simulation, we adjust a closure depth according to pertinent wave conditions based on the Hallermeier's analytical model (1978) having its roots on the Shield's parameter. Numerical results show that from 2017.4.26 to 2017.10.15 during which swells are prevailing, a shoreline advances due to the sustained supply of cross-shore sediment. It is also shown that a shoreline temporarily retreats due to the erosion by the yearly highest waves sequentially occurring from mid-October to the end of October, and is followed by gradual recovery of shoreline as high waves subdue and swells prevail. It is worth mentioning that great yearly circulation of shoreline completes when a shoreline retreats due to the erosion by the higher waves occurring from mid-March to the end of March. The great yearly circulation of shoreline mentioned above can also be found in the measured locations of shoreline on 2017.4.5, 2017.9.7, 2017.11.7, 2018.3.14. However, numerically simulated amount of shoreline retreat or advance is more significant than the physically measured one, and it should be noted that these discrepancies become more substantial for the case of RUN II where a closure depth is sustained to be as in the most morphology models like the Genesis (Hanson and Kraus, 1989).

Consideration of a Bacteria Contamination Management in the Dispensation of 99mTc Radiopharmaceutical (테크네슘 방사성의약품의 조제와 분배 과정에서 오염균에 대한 고찰)

  • Choi, Do Chul;Gim, Yeong Su;Jo, Gwang Mo;Gim, Hui Jeong;Seo, Han Gyeong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.2
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    • pp.84-87
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    • 2018
  • Purpose The radiopharmaceutical used in the nuclear medicine department is used only for the specific patient according to the prescription or instruction of the doctor without selling, so it is dispensed and it is distributed and used for the examination. Radiopharmaceuticals administered to patients should be managed appropriately as well as radiation safety management during dispensation. The purpose of this study is to investigate microbial contamination during dispensation of radiopharmaceuticals Materials and Methods This study distinguished between general workbench and clean workbench and performed three tests. First, microbial cultivation test of radiopharmaceutical prepared and dispensed in general workbenches and sterile workbenches were carried out five times, respectively. The second test was performed settle plate method three times before and after the use of the exhaust filter. Finally, Adenosine Triphosphate (ATP) measurement was performed in each workbench to measure bacterial counts. In addition, ATP measurement were carried out by designating locations and items that may be contaminated during dispensation. Results In the microbial culture test, no microorganisms were detected in both samples. In the settle plate method, it was detected without using of the exhaust filter in a general workbench once. In the ATP measurement test, it was measured at the level of 400 RLU or less, which is the standard value of contamination, in both workbenches surface. In additional ATP measurement test, the refrigerator handle in the distribution room was measured above the reference value of 1217 RLU, the vacuum vial shield of the Tech Generator at 435 RLU, and the syringe holder at 1357 RLU. After environmental disinfection, the results were reduced to 311 RLU, 136 RLU, and 291 RLU. Conclusion No contamination by bacteria was found in both workbenches. However, microbial contamination may occur if the use of an exhaust filter or proper hand hygiene is not achieved. Regular inspections and management for aseptic processing themselves will be necessary.

Analysis of Gwonbeop(拳法) in traditional martial arts literature (전통무예서의 권법 분석)

  • Kwak, Nak-hyun;Lim, Tae-hee
    • (The)Study of the Eastern Classic
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    • no.54
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    • pp.289-318
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    • 2014
  • The purpose of this study was to compare Gwonbeop motions among "Gihyosinseo", "Mubiji", "Muyejaebobunyuksokjib" and to analysis catalogue of books on Gwonbeop for comprehensive interpretation in "Muyedobotongji". the conclusion through literature review was as follows. First, There were total 16 references which were composed of 14 references of China and 2 references of Korea. In particular there was no reference of Japan for Gwonbeop. In detail, unrepresentative references of China were "Hanseo", "Gihyosinseo", "Mubiji" and unrepresentative reference of Korea was Muyejaebobunyuksokjib". Second, We compared motions of Gwonbeop between China and Korea. There were located 5 motions such as Gyungakguheese(False Prey Posture), Gigose(Flag Beating Posture), Ahnshichukshinse(Goose Wing Posture), Jumjoose(Picking Elbow Posture), Pogase(Throwing Shelf Postere). In other three references unmentioned "Mubiji" there were located 8 motions such as Jungranse(Spring Railing Posture), Gichukgakse(Ghost Kicking and Leg Striking Postere), Jidangse(Open Finger Attacking Posture), Soodoose(Beast Head Shield Posture) Shingwon(Heavenly Fist Posture), Il-jopyunse(Whipping Lunging Posture), Jakjiryongse(Dragon Prey Snatching Posture), Joyangsoose(Slanting Hero Hand Posture), In two references of Korea there were located 2 unique motions such as Nachaluichoolmun Gakabyunhase(Low Encountering Posture), Gumgyedongnipse(Single Leg Throwing Postere). Third, Most of all we found two kinds of unique motions such as Chukcheonse and Eungswaeik on "Muyejaebobunyuksokjib" and such as Nachaluichoolmun Gakabyunhase(Low Encountering Posture), Gumgyedongnipse (Single Leg Throwing Postere) on "Muyedobotongji". Based on chronological table although "Gihyosinseo" is the longest literature, there was begun changing techniques in details on literatures of Korea. Transformed into techniques of Gwonbeop on Korea could be supposed that those skills were reflected in society and culture of the Joseon Dynasty. To sum it up, Gwonbeop of "Muyedobotongji" was written by "Gihyosinseo", "Mubiji", "Muyejaebobunyuksokjib" but most motions of Gwonbeop were begun to change gradually except 5 motions of "Gihyosinseo". Especially, there were 8 unique motions which could not be found in references of China. Those unique motions of Korea literatures were living proof of attempting transfiguration from motions of China. The significance of this study was to be able to put stepping-stone to interpretate history of Taekwondo which takes center stage on bare hands martial arts and analyzed the meaning of historical martial arts on Gwonbeop in Joseon Dynasty.

Activation Evaluation of Radiation Shield Wall (Concrete) in Cyclotron room using the Portable Nclide Analyzer Running Title: Activation Evaluation of Concrete in Cyclotron room (휴대용 핵종분석기를 활용한 사이클로트론실 내 차폐벽 방사화 평가)

  • Kim, Seongcheol;Gwon, Da Yeong;Jeon, Yeoryeong;Han, Jiyoung;Kim, Yongmin
    • The Korean Journal of Nuclear Medicine Technology
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    • v.25 no.2
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    • pp.41-47
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    • 2021
  • Purpose There are many cyclotrons compared to the land area of the Republic of Korea. Because GMP certification is required and the nuclear medicine test does not apply for insurance, the number of examinations for nuclear medicine is decreasing. Therefore, there is a high probability of early decommissioning of the cyclotron. However, we do not unusually perform the radioactivation evaluation on concrete that can be classified as radioactive waste during the decommissioning of the cyclotron. In this study, we aim to confirm the radioactivation in the concrete surface using Handheld Radionuclide Identification Devices (RIDs). Materials and Methods Because there is no cyclotron being decommissioning in the Republic of Korea, it was impossible to perform the coring of concrete for radioactivation analysis. In this study, we used the KIRAMS-13 and analyzed the concrete surface in the target direction in the cyclotron room. After setting the target direction as the center, radionuclides were measured for about five months at thirty points with vertical and horizontal intervals of 30 cm. We used the RIIDEye(Detector: NaI(Tl) detector, manufacturer: Thermo) in this study and set the measurement time per point to one day (24 hours). Results Co-60 and Cs-137 were detected in some measurement points, and we confirmed the radioactivity of Co-60 detected at the most points. As a result, we found that the radioactivity of Co-60 was high in the diagonal direction (from the lower-left direction to the upper right direction) based on the center of the target. However, we think it is impossible to apply the corresponding results to all cyclotrons because we performed the study using only one cyclotron. Conclusion In thirty measurement points, we could confirm the radioactive nuclides and the relative radioactivity using the results of portable nuclides analyzer. Therefore, we expect that we can use the portable nuclides analyzer to select the coring position of concrete during the decommissioning of the cyclotron. Also, if we secure the radioactivation data for several years, we expect to make a more accurate estimate of radioactive waste during the preparation period of decommissioning of the cyclotron.

Cultivation of Ginseng in Baengnyeongdo, the Northernmost Island of the Yellow Sea in South Korea (서해 최북단 섬 백령도의 인삼 재배 현황)

  • Cho, Dae-Hui
    • Journal of Ginseng Culture
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    • v.4
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    • pp.128-141
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    • 2022
  • Baengnyeongdo Island, which belongs to Ongjin-gun, Incheon, is an island in the northernmost part of the West Sea in South Korea. Baengnyeong Island is the 15th largest island in Korea and covers an area of 51 km2. The Korea Ginseng Corporation (KGC) investigated the possibility of growing ginseng on Baengnyeong Island in 1996. In 1997, thanks to the support of cultivation costs from Ongjin-gun, the first ginseng seedbed was built on Baengnyeong Island. In 1999, the seedlings were transplanted to a permanent field under a contract with KGC. In 2003, the first six-year-old ginseng harvest was performed, and KGC purchased all production according to the contract. Since then, KGC has signed on to grow ginseng until 2012 and purchased six-year-old ginseng until the fall of 2016. Since 2014, the GimpoPaju Ginseng Agricultural Cooperative Association has signed a ginseng production contract. According to a survey of nine 6-year-old ginseng fields (total 5,961 units) on Baengnyeong Island, the top five with good growth had a survival rate of 42.6 to 68%, and the bottom four with poor growth had an extremely low survival rate of 11.1 to 21.3%. The four fields with low survival rates were where hot peppers were planted before ginseng cultivation. It is believed that the excess nitrogen remaining in the soil due to the treatment of compost or manure during pepper cultivation causes ginseng roots to rot. The average incidence of Alternaria blight was 8.6%. Six six-year-old ginseng gardens were low at 1.1 to 4.7%, while the other three were high at 16.7 to 20.9%. It is assumed that the reason for the low survival rate and high incidence of Alternaria blight is a rain-leaking shield. Farmers used rain-leaking shields because the precipitation on Baengnyeong Island was smaller than on land. One field showed 3% of leaves with yellowish brown spots, a symptom of physiological disturbance of the leaf, which is presumed to be due to the excessive presence of iron in the soil. To increase the production of ginseng on Baengnyeong Island, it is necessary to develop a suitable ginseng cultivation method for the island, such as strengthening the field management based on the results of a scientific study of soil, using rain-resistant shading, and installing drip irrigation facilities. I hope that ginseng will become a new driving force for the development of Baengnyeong Island, allowing ginseng products and food to thrive in the beautiful natural environment of the island.

The Effects of Increased Temperature on Yield Properties, Antioxidant Contents, and Pollen Viability of Adzuki Bean (Vigna angularis L.) Responses in Temperature Gradient Greenhouse and Growth Periods (온도구배온실에서 온도상승이 생육시기별 팥의 수량, 항산화 성분, 화분 임성에 미치는 영향)

  • Eun Ji Suh;Ok Jae Won;Jae-Sung Park;Won Young Han;Jin Hee Seo;Sun Tae Kim;Hye Rang Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.2
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    • pp.47-58
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    • 2023
  • The quality and yield of crops produced using field cultivation are expected to decrease due to the recent global climate change caused by extreme weather. The plant reproductive stage associated with crop yields is a highly vulnerable period to global warming caused by high temperatures. This study analyzed the adzuki bean's yield properties, antioxidant contents, and pollen viability of adzuki bean (Vigna angularis L.) under high-temperature stress and growth periods in a temperature gradient greenhouse that forms 0 to 4℃ above the outside temperatures. As the main variety of red beans cultivated in Korean farms, the "Arari" red bean was grown in the rain shield greenhouse and the temperature gradient greenhouse from 2021 to 2022 in Milyang, Korea. Compared to 2022, it showed a 0 - 1.0℃ lower temperature during the whole growth period in 2021. However, its average temperatures were 0 - 3.7℃ higher in the vegetative stage and 0.4 - 2.4℃ higher in the anthesis stage in 2021. The lowest yield (6.8 ± 0.7 g) was at the highest temperature (T4: low, 23.6℃; average, 28.5℃; high, 35.8℃) during the anthesis stage in 2021. The temperatures of the mature stage were 1.7 - 3.9℃, which were higher in 2022 than in 2021, although the low temperatures of 2022 were lower than in 2021. The yields of the mature stage in 2022 increased more than in 2021 because of the high temperature of the mature stage. The growth and yield were good at 40.5℃ in the vegetative stage. However, growth was poor when the average temperature was 27.0℃ or higher, and yields decreased during the flowering period. Total polyphenol and flavonoid contents were increased, and the pollen viability was 40.75% in the whole growth period at high temperature (T4: low, 22.9℃; average, 28.8℃; high, 36.9℃). These results showed that the antioxidant levels increased when the antioxidant component was affected at higher temperatures than at normal. In contrast, the pollen viability-related yield decreased as the temperature increased. Our results are the basic data for field growers and the breeding of thermos-tolerance in adzuki beans to prepare for the changeable future climate.

Research on Radiation Shielding Film for Replacement of Lead(Pb) through Roll-to-Roll Sputtering Deposition (롤투롤 스퍼터링 증착을 통한 납(Pb) 대체용 방사선 차폐필름 개발)

  • Sung-Hun Kim;Jung-Sup Byun;Young-Bin Ji
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.441-447
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    • 2023
  • Lead(Pb), which is currently mainly used for shielding purposes in the medical radiation, has excellent radiation shielding functions, but is continuously exposed to radiation directly or indirectly due to the harmfulness of lead itself to the human body and the inconvenience caused by its heavy weight. Research on shielding materials that are human-friendly, lightweight, and convenient to use that can block risks and replace lead is continuously being conducted. In this study, based on the commonly used polyethylene terephthalate (PET) film and the fabric material used in actual radiation protective clothing, a multi-layer thin film was realized through sputtering and vacuum deposition of bismuth, tungsten, and tin, which are metal materials that can shield radiation. Thus, a shielding film was produced and its applicability as a radiation shielding material was evaluated. The radiation shielding film was manufactured by establishing the optimized conditions for each shielding material while controlling the applied voltage, roll driving speed, and gas supply amount to manufacture the shielding film. The adhesion between the parent material and the shielding metal thin film was confirmed by Cross-cut 100/100, and the stability of the thin film was confirmed through a hot water test for 1 hour to measure the change of the thin film over time. The shielding performance of the finally realized shielding film was measured by the Korea association for radiation application (KARA), and the test conditions (inverse wide beam, tube voltage 50 kV, half layer 1.828 mmAl) were set to obtain an attenuation ratio of 16.4 (initial value 0.300 mGy/s, measured value 0.018 mGy/s) and damping ratio 4.31 (initial value 0.300 mGy/s, measured value 0.069 mGy/s) were obtained. by securing process efficiency for future commercialization, light and shielding films and fabrics were used to lay the foundation for the application of films to radiation protective clothing or construction materials with shielding functions.