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New thyroid models for ICRP pediatric mesh-type reference computational phantoms

  • Yeon Soo Yeom ;Chansoo Choi ;Bangho Shin ;Suhyeon Kim ;Haegin Han ;Sungho Moon ;Gahee Son;Hyeonil Kim;Thang Tat Nguyen;Beom Sun Chung;Se Hyung Lee ;Chan Hyeong Kim
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4698-4707
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    • 2022
  • As part of the ICRP Task Group 103 project, we developed ten thyroid models for the pediatric mesh-type reference computational phantoms (MRCPs). The thyroid is not only a radiosensitive target organ needed for effective dose calculation but an important source region particularly for radioactive iodines. The thyroid models for the pediatric MRCPs were constructed by converting those of the pediatric voxel-type reference computational phantoms (VRCPs) in ICRP Publication 143 to a high-quality mesh format, faithfully maintaining their original topology. At the same time, we improved several anatomical parameters of the thyroid models for the pediatric MRCPs, including the mass, overlying tissue thickness, location, and isthmus dimensions. Absorbed doses to the thyroid for the pediatric MRCPs for photon external exposures were calculated and compared with those of the pediatric VRCPs, finding that the differences between the MRCPs and VRCPs were not significant except for very low energies (<0.03 MeV). Specific absorbed fractions (target ⟵ thyroid) for photon internal exposures were also compared, where significant differences were frequently observed especially for the target organs/tissues close to the thyroid (e.g., a factor of ~1.2-~327 for the thymus as a target) due mainly to anatomical improvement of the MRCP thyroid models.

The Role of Processing Fluency in Product Innovativeness Judgment

  • Cho, Hyejeung
    • Asia Marketing Journal
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    • v.15 no.3
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    • pp.31-52
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    • 2013
  • The metacognitive experience of the ease or difficulty with which new, external information can be processed, referred to as 'processing fluency,' has been shown to influence a wide range of human judgments including truth judgments, familiarity judgments, risk perception, evaluation, and preference (see Alter and Oppenheimer 2009 for a review). The current research explores the possibility of a consumer's product innovativeness judgment based on the difficulty of processing new information. In specific, this study examines if the inferential link between (dis)fluency-(un)familiarity can feed into the perception of innovativeness. This study also explores how a consumer's processing motivation can moderate the consumer's reliance on processing fluency in judgments and how the influence of fluency can vary depending on judgment task orders. In an experiment, participants rated a new product's innovativeness and then indicated their product attitude (or vice versa depending on the judgment task order condition) after reading a product review article that was printed in either an easy-to-read or a difficult-to-read font (for fluency manipulation). The findings show that low need for cognition individuals infer higher product innovativeness when processing product information is difficult rather than easy, consistent with the common assumption that 'new information is more difficult to process than familiar information.' The findings also suggest that once low fluency is attributed to innovativeness, it may no longer lead to a negative response to the product. High need for cognition individuals' judgments on product innovativeness are not affected by fluency. The findings also demonstrate a judgment task order effect on the use of fluency in judgments (e.g., Xu and Schwarz 2005). This study provides the first evidence that an individual's fluency experience can be used as a source of information in product innovativeness judgments especially under low processing motivation conditions. The findings can help marketers better understand the malleability of consumer judgments and perceptions of product characteristics (e.g., product innovativeness) by demonstrating an interesting interplay of processing fluency, processing motivation, and judgment task-related contextual factors.

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A Study on the South Korean Media toward Science and Technology of North Korea in the Era of Kim Jong-Un: Based on the Analysis of Framing and Information Source

  • Jaeryoung Song;Ami Woo
    • Asian Journal of Innovation and Policy
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    • v.12 no.2
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    • pp.177-199
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    • 2023
  • In traditional studies on North Korea, conservative media in South Korea generally report and have an attitude toward anti-North Korea. It is a similar context as South Korea's conservatives view the U.S. and Japan more closely and positively than North Korea. This study is about how the reporting frames and information sources on North Korean science and technology in South Korea's conservative and progressive media differ and show trends. As a result of analyzing the reporting frame on North Korean science and technology by conservative and progressive media, progressive media showed similar trends or slightly positive responses to North Korean science and technology. But the reanalyzed result after dividing it into conservative and progressive governments, the opposite result came out. In the conservative government, the progressive media dealt with very positive aspects of North Korea's science and technology, and in the progressive government, there was a clear tendency to report negative rather than positive. What can be inferred from this is that the progressive media of South Korea had at least quite different directions of the progressive government in dealing with North Korean science and technology, but rather close to anti-North Korea. It is difficult to reach a hasty conclusion because this study has not dealt with all the press and only 10 years after the Kim Jong-Un regime. Nevertheless, this study may provide implications in that it is the first study to analyze how South Korean conservative and progressive media frame North Korean science and technology.

The Development of Laboratory Instruction Classification Scheme (실험수업 유형 분류틀 개발)

  • Yang, Il-Ho;Jeong, Jin-Woo;Hur, Myung;Kim, Seog-Min
    • Journal of The Korean Association For Science Education
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    • v.26 no.3
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    • pp.342-355
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    • 2006
  • The purpose of this study was to develop a classification scheme for laboratory instruction, which could occupy a central and distinctive role in science education. For this study, literature on laboratory instruction types were analyzed. Utilizing several of these theoretical frameworks, a Classification Scheme for Laboratory Instruction (CSLI), which clearly represents various features of laboratory instruction, was created. The developed CSLI consisted of two descriptors: one is the procedure for laboratory instruction, and the other is a way of approach. The procedure is either designed by the students or provided for them from an external source. A dichotomy also exists for the approach taken toward the activity: deductive or inductive. Validity was established for the CSLI. In addition, laboratory instruction according to CSLI was divided into four types: verification, discovery, exploratory, and investigation. Although this study demonstrated only limited features of laboratory instruction due to the absence of a field test, it serves as a model for more comprehensive studies.

Understanding Thermal Runaway Phenomena in Overcharged Lithium-Ion Batteries (리튬이차전지의 과충전에 의한 열폭주 현상의 이해)

  • Minseo Lee;Ji-sun You;Kyeong-sin Kang;Jaesung Lee;Sungyool Bong
    • Journal of the Korean Electrochemical Society
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    • v.27 no.2
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    • pp.55-72
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    • 2024
  • Secondary batteries are used as an essential renewable energy source in our lives, such as electric vehicles and energy storage systems (ESS), as an alternative to fossil fuels due to global warming. However, cases of battery fires and explosions have been reported due to thermal runaway in secondary batteries due to various causes such as overdischarge, high-speed charging and discharging, and external short circuit, and great efforts are being made to find solutions suitable for each cause. In particular, as cases presumed to be caused by the overcharging process have been reported, this review will examine the chemical reactions of secondary batteries that can occur during the overcharging process and discuss risk investigation methods to check and prevent them.

Dose Assessment for Workers in Accidents (사고 대응 작업자 피폭선량 평가)

  • Jun Hyeok Kim;Sun Hong Yoon;Gil Yong Cha;Jin Hyoung Bai
    • Journal of Radiation Industry
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    • v.17 no.3
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    • pp.265-273
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    • 2023
  • To effectively and safely manage the radiation exposure to nuclear power plant (NPP) workers in accidents, major overseas NPP operators such as the United States, Germany, and France have developed and applied realistic 3D model radiation dose assessment software for workers. Continuous research and development have recently been conducted, such as performing NPP accident management using 3D-VR based on As Low As Reasonably Achievable (ALARA) planning tool. In line with this global trend, it is also required to secure technology to manage radiation exposure of workers in Korea efficiently. Therefore, in this paper, it is described the application method and assessment results of radiation exposure scenarios for workers in response to accidents assessment technology, which is one of the fundamental technologies for constructing a realistic platform to be utilized for radiation exposure prediction, diagnosis, management, and training simulations following accidents. First, the post-accident sampling after the Loss of Coolant Accident(LOCA) was selected as the accident and response scenario, and the assessment area related to this work was established. Subsequently, the structures within the assessment area were modeled using MCNP, and the radiation source of the equipment was inputted. Based on this, the radiation dose distribution in the assessment area was assessed. Afterward, considering the three principles of external radiation protection (time, distance, and shielding) detailed work scenarios were developed by varying the number of workers, the presence or absence of a shield, and the location of the shield. The radiation exposure doses received by workers were compared and analyzed for each scenario, and based on the results, the optimal accident response scenario was derived. The results of this study plan to be utilized as a fundamental technology to ensure the safety of workers through simulations targeting various reactor types and accident response scenarios in the future. Furthermore, it is expected to secure the possibility of developing a data-based ALARA decision support system for predicting radiation exposure dose at NPP sites.

Design Characteristics of Augmented Reality Digital Fashion (증강 현실 디지털 패션의 디자인 특성)

  • Eunjeong Kim;Seunghee Suh
    • Journal of Fashion Business
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    • v.28 no.4
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    • pp.1-20
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    • 2024
  • The aim of this study was to analyze contemporary sociocultural phenomena and values through characteristics of augmented reality (AR) digital fashion design. The research method included a literature review on the metaverse and augmented reality, combined with a case study using both quantitative analysis through big data text mining and qualitative analysis through constant comparison. Data analysis was conducted using Python-based open-source tools: First, 6,725 data entries were collected from AR digital fashion platforms and brands identified in articles from Vogue and Vogue Business containing keywords of 'augmented reality' and 'digital fashion. Second, text preprocessing involved stop word removal, tokenization, and POS-tagging of nouns and adjectives using the NLTK library. Third, top 50 keywords were extracted through term frequency (TF) and TF-IDF analysis, with results visualized using a word cloud. Fourth, characteristics of products' external design and internal concepts that contained top keywords were classified, with their value examined through repeated comparison. Results indicate that AR digital fashion design has the following characteristics. First, it embodies surreal fantasy through designs that mimic natural biological patterns using 3D scanning and modeling technology. Second, it presents a trans-boundary aspect by utilizing the fluidity of body and space to challenge vertical and discriminatory social structures. Third, it imagines a new future transcending traditional sociocultural concepts by expanding perceptions of space and time based on advanced technological aesthetics. Fourth, it contributes to sustainability by exploring alternatives for the fashion industry in response to climate change and ecological concerns.

Treatment of Carcinoma of the Uterine Cervix with High-Dose-Rate Intracavitary Irradiation using Ralstron (고선량률 강내조사를 사용한 자궁경부암의 치료)

  • Suh Chang Ok;Kim Gwi Eon;Loh John J.K.
    • Radiation Oncology Journal
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    • v.8 no.2
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    • pp.231-239
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    • 1990
  • From May 1979 through December 1981 a total of 524 patients with carcinoma of the uterine cervix were treated by radiation therapy with curative intent. Among the 524 patients, 350 were treated with a high-dose-rate (HDR), remote-controlled, afterloading intracavitary irradiation (ICR) system using a cobalt source (Ralstron), and 168 patients received a low-dose-rate (LDR) ICR using a radium source. External beam irradiation with a total dose of 40-50 Gy to the whole pelvis followed by intracavitary irradiation with a total dose of 30-39 Gy in 10-13 fractions to point A was the treatment protocol. ICR was given three times a week with a dose of 3 Gy per fraction. Five-year actuarial survival rates in the HDR-ICR group were $77.6{\%}$ in stage IB (N=20), $68.2{\%}$ in stage II (N=182), and $50.9{\%}$ in stage III (N=148). In LDR-ICR group, 5-year survival rates were $87.5{\%}$ in stage IB (N=22), $66.3{\%}$ in stage II (N=91), and $55.4{\%}$ in stage III (N=52). Survival rates showed a statistically significant difference by stage, but there was no significant difference between the two ICR groups. Late bowel complications after radiotherapy were noted in $3.7{\%}$ of the HDR-ICR group and $8.4{\%}$ of the LDR-ICR group. There was no severe complication requiring surgical management. The incidence of bladder complications was $1.4{\%}$ in the HDR-ICR group and $2.4{\%}$ in the LDR-ICR group. The application of HDR-ICR was technically simple and easily performed on an outpatient basis without anesthesia, and the patients tolerated it very well. Radiation exposure to personnel was virtually nil in contrast to that of LDR-ICR. Within a given period of time, more patients can be treated with HDR-ICR because of the short treatment time. Therefore, the HDR-ICR system is highly recommended for a cancer center, particularly one with a large number of patients to be treated. In order to achieve an improved outcome, however, the optimum dose-fractionation schedule of HDR-ICR and optimum combination of intracavitary irradiation with external beam irradiation should be determined through an extensive protocol.

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Development of New BNR Process Using Fixed-Biofilm to Retrofit the Existing Sewage Treatment Plant (고정생물막을 이용한 기존 하수처리장의 생물학적 영양염 제커 신공정개발)

  • Kim, Mi-Hwa;Lee, Ji-Hyung;Chun, Yang-Kun;Park, Tae-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.6
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    • pp.1093-1101
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    • 2000
  • The object of this study was to develop new BNR process using fixed-biofilm which could be applied to retrofit the existing wastewater treatment plant or to introduce as tertiary treatment plant. To achieve complete denitrification from typical raw sewage in Korea, external carbon source must be supplied because $SCOD_{cr}/T-N(NH_4{^+}-N+NOx-N)$of raw sewage was lower than other countries. In this study, the ratio of $SCOD_{cr}/NH_4{^+}-N$ was 2.49 and the influent $NH_4{^+}$-N concentration during the experimental period was varied from 25 to 37 mg/L. To enhance nitrogen removal from the sewage, the two processes using fixed biofilm were adopted as R-Hanoxic/mid.settler/aerobic/anoxic/ aerobic) and R-2(aerobic/mid.settlerlanoxic/anoxic/aerobic), respectively. In the comparison of $NH_4{^+}$-N, T-N effluent quality and T-N removal efficiency in both processes without external carbon source, R-1 process was better than R-2 process for nitrogen removal from raw sewage. With respect to $SCOD_{cr}$/NOx-N ratio and total nitrogen removal in each anoxic reactor of two processes, R-1's was more effective than R-2's for distributing organic matters of raw sewage. In the both processes using fixed biofilm, the amount of required alkalinity to remove unit $NH_4{^+}$-N were 5.18 and 5.76($g{\cdot}CaCO_3/g{\cdot}NH_4{^+}-N_{removed}$), respectively and were lower than activated sludge BNR process(7.14).

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High-Dose-Rate Brachytherapy for Uterine Cervical Cancer : The Results of Different Fractionation Regimen (자궁경부암의 고선량률 근접치료 : 분할선량에 따른 결과 비교)

  • Yoon, Won-Sup;Kim, Tae-Hyun;Yang, Dae-Sik;Choi, Myung-Sun;Kim, Chul-Yong
    • Radiation Oncology Journal
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    • v.20 no.3
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    • pp.228-236
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    • 2002
  • Purpose : Although high-dose-rate (HDR) brachytherapy regimens have been practiced with a variety of modalities and various degrees of success, few studies on the subject have been conducted. The purpose of this study was to compare the results of local control and late complication rate according to different HDR brachytherapy fractionation regimens in uterine cervical cancer patients. Methods and Materials : From November 1992 to March 1998, 224 patients with uterine conical cancer were treated with external beam irradiation and HDR brachytherapy. In external pelvic radiation therapy, the radiation dose was $45\~54\;Gy$ (median dose 54 Gy) with daily fraction size 1.8 Gy, five times per week. In HDR brachytherapy, 122 patients (Group A) were treated with three times weekly with 3 Gy to line-A (isodose line of 2 cm radius from source) and 102 patients (Group B) underwent the HDR brachytherapy twice weekly with 4 or 4.5 Gy to line-A after external beam irradiation. Iridium-192 was used as the source of HDR brachytherapy. Late complication was assessed from grade 1 to 5 using the RTOG morbidity grading system. Results : The local control rate (LCR) at 5 years was $80\%$ in group A and $84\%$ in group B (p=0.4523). In the patients treated with radiation therapy alone, LCR at 5 years was $60.9\%$ in group A and $76.9\%$ in group B (p=0.2557). In post-operative radiation therapy patients, LCR at 5 years was $92.6\%$ In group A and $91.6\%$ in group B (p=0.8867). The incidence of late complication was $18\%$ (22 patients) and $29.4\%$ (30 patients), of bladder complication was $9.8\%$ (12 patients) and $14.7\%$ (15 patients), and of rectal complication was $9.8\%$ (12 patients) and $21.6\%$ (22 patients), in group A and B, respectively. Lower fraction sized HDR brachytherapy was associated with decrease in late complication (p=0.0405) (rectal complication, p=0.0147; bladder complication, p=0.115). The same result was observed in postoperative radiation therapy patients (p=0.0860) and radiation only treated patients (0=0.0370). Conclusion : For radiation only treated patients, a greater number of itemized studies on the proper fraction size of HDR brachytherapy, with consideration for stages and prognostic factors, are required. In postoperative radiation therapy, the fraction size of HDR brachytherapy did not have much effect on local control, yet the incidence of late complication increased with the elevation in fraction size. We suggest that HDR brachytherapy three times weekly with 3 Gy could be an alternative method of therapy.