• Journal of Electrochemical Science and Technology
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• v.14 no.4
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• pp.388-396
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• 2023

Photoelectrochemical (PEC) water splitting is a vital source of clean and sustainable hydrogen energy. Moreover, the large-scale H₂ production is currently necessary, while long-term stability and high PEC activity still remain important issues. In this study, a GaN-based photoelectrode was modified by an additional NH₃ treatment (900℃ for 10 min) and its PEC behavior was monitored. The bare GaN exhibited a highly crystalline wurtzite structure with the (002) plane and the optical bandgap was approximately 3.2 eV. In comparison, the NH₃-treated GaN film exhibited slightly reduced crystallinity and a small improvement in light absorption, resulting from the lattice stress or cracks induced by the excessive N supply. The minor surface nanotexturing created more surface area, providing electroactive reacting sites. From the surface XPS analysis, the formation of an N-Ga-O phase on the surface region of the GaN film was confirmed, which suppressed the charge recombination process and the positive shift of E_FB. Therefore, these effects boosted the PEC activity of the NH₃-treated GaN film, with J values of approximately 0.35 and 0.78 mA·cm^-2 at 0.0 and 1.23 V_RHE, respectively, and an onset potential (V_on) of -0.24 V_RHE. In addition, there was an approximate 50% improvement in the J value within the highly applied potential region with a positive shift of V_on. This result could be explained by the increased nanotexturing on the surface structure, the newly formed defect/trap states correlated to the positive V_on shift, and the formation of a GaO_xN_1-x phase, which partially blocked the charge recombination reaction.

• Journal of Radiation Protection and Research
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• v.48 no.3
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• pp.131-143
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• 2023

Background: This study examined the detection limit of thyroid screening monitoring conducted at the time of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 using a Monte Carlo simulation. Materials and Methods: We calculated the detection limit of a NaI(Tl) survey meter to measure ¹³¹I accumulation in the thyroid gland of children. Mathematical phantoms of 1- and 5-year-old children were developed in the simulation of the Particle and Heavy Ion Transport code System code. Contamination of the body surface with eight radionuclides found after the FDNPP accident was assumed to have been deposited on the neck and shoulder area. Results and Discussion: The detection limit was calculated as a function of ambient dose rate. In the case of 40 Bq/cm² contamination on the body surface of the neck, the present simulations showed that residual thyroid radioactivity corresponding to thyroid dose of 100 mSv can be detected within 21 days after intake at the ambient dose rate of 0.2 µSv/hr and within 11 days in the case of 2.0 µSv/hr. When a time constant of 10 seconds was used at the dose rate of 0.2 µSv/hr, the estimated survey meter output error was 5%. Evaluation of the effect of individual differences in the location of the thyroid gland confirmed that the measured value would decrease by approximately 6% for a height difference of ±1 cm and increase by approximately 65% for a depth of 1 cm. Conclusion: In the event of a nuclear disaster, simple measurements carried out using a NaI(Tl) scintillation survey meter remain effective for assessing ¹³¹I intake. However, it should be noted that the presence of short-half-life radioactive materials on the body surface affects the detection limit.

• Hip & pelvis
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• v.34 no.4
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• pp.236-244
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• 2022

Purpose: The most recent diagnostic criteria for periprosthetic joint infection (PJI) include the use of the alpha-defensin (AD) lateral-flow (LF) test, but hip and knee arthroplasties were usually combined in previous studies. This prospective study was designed to examine the accuracy of the AD-LF test for diagnosis of PJI in chronic painful total hip arthroplasties (THA). Materials and Methods: Patients with chronic painful hip arthroplasties were prospectively enrolled between March 2018 and May 2020. Exclusion criteria included acute PJI or an insufficient amount of synovial fluid. The modified Musculoskeletal Infection Society (MSIS) criteria were primarily used for PJI diagnosis. Fifty-seven patients were included in the analysis group. Revision surgery was not performed in 38 patients, for different reasons (clinical group); these patients remain "Schrödinger's hips": in such cases PJI cannot be excluded nor confirmed until you "open the box". Results: The result of the AD-LF test was positive in nine patients and negative in 48 patients. Six patients were diagnosed with PJI. AD-LF sensitivity (MSIS criteria) was 83% (95% confidence interval [CI] 36-100%) and specificity was 92% (95% CI 81-98%). The positive and negative predictive value were 56% and 98%, respectively. Conclusion: The AD test is useful in addition to the existing arsenal of diagnostic tools, and can be helpful in the decision-making process. Not all patients with chronical painful THA will undergo revision surgery. Consequently, in order to determine the reliable diagnostic accuracy of this test, future PJI diagnostic studies should include a second arm of "Schrödinger's hips".

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.26 no.3
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• pp.277-280
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• 2022

Backgrounds/Aims: Biliary colic is a common cause of emergency department (ED) visits; however, the natural history of the disease and thus the indications for urgent or scheduled surgery remain unclear. Limitations of previous attempts to elucidate this natural history at a population level are based on the reliance on the identification of biliary colic via administrative codes in isolation. The purpose of our study was to validate the use of International Statistical Classification of Diseases and Related Health Problems codes, 10th Revision, Canadian modification (ICD-10-CA) from ED visits in adequately differentiating patients with biliary colic from those with other biliary diagnoses such as cholecystitis or common bile duct stones. Methods: We performed a retrospective validation study using administrative data from two large academic hospitals in Toronto. We assessed all the patients presenting to the ED between January 1, 2012 and December 31, 2018, assigned ICD-10-CA codes in keeping with uncomplicated biliary colic. The codes were compared to the individually abstracted charts to assess diagnostic agreement. Results: Among the 991 patient charts abstracted, 26.5% were misclassified, corresponding to a positive predictive value of 73% (95% confidence interval 73%-74%). The most frequent reasons for inaccurate diagnoses were a lack of gallstones (49.8%) and acute cholecystitis (27.8%). Conclusions: Our findings suggest that the use of ICD-10 codes as the sole means of identifying biliary colic to the exclusion of other biliary pathologies is prone to moderate inaccuracy. Previous investigations of biliary colic utilizing administrative codes for diagnosis may therefore be prone to unforeseen bias.

• Advanced Industrial SCIence
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• v.3 no.3
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• pp.8-13
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• 2024

Zero Knowledge Proof (ZKP) is an innovative decentralized technology designed to enhance the privacy and security of virtual currency transactions. By ensuring that only the necessary information is disclosed by the transaction provider, ZKP protects the confidentiality of all parties involved. This ensures that both the identity of the transacting parties and the transaction value remain confidential.ZKP not only provides a robust privacy function by concealing the identities and values involved in blockchain transactions but also facilitates the exchange of money between parties without the need to verify each other's identity. This anonymity feature is crucial in promoting trust and security in financial transactions, making ZKP a pivotal technology in the realm of virtual currencies. In the context of the Fourth Industrial Revolution, the application of ZKP contributes significantly to the comprehensive and stable development of financial services. It fosters a trustworthy user environment by ensuring that transaction privacy is maintained, thereby encouraging broader adoption of virtual currencies. By integrating ZKP, financial services can achieve a higher level of security and trust, essential for the continued growth and innovation within the sector.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.142-153
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• 2019

The Joseon Dynasty (1392-1910) left behind a wealth of documentary heritage, including collections of literary works, personal letters, and journals, as well as public documents such as Veritable Records of the Joseon Dynasty (Joseon Wangjo Sillok), Diaries of the Royal Secretariat (Seungjeongwon Ilgi), and State Protocols (Uigwe). Such heritage also includes personal diaries that have been highly regarded for their frank and vivid records of people's lives in the Joseon period. There have been great diaries published and intended for reading by the Korean public, including War Diaries (Nanjung Ilgi, 1592~1598) by Yi Sun-sin and Diaries of Jehol (Yeolha Ilgi, 1780) by Park Ji-won. Unfortunately, a great majority of these personal records remain unknown to the world. Such great records have not been given an opportunity to be documented properly, but are left outside public attention, abandoned to be damaged and destroyed. Few personal diaries of the Joseon period were written on good-quality paper. After the death of their authors, these diaries were left to be kept by their descendants; this explains why many of these records have been in poor condition, particularly when compared with the public records published by the government of Joseon, such as Sillok and Uigwe, even when these were lucky enough to be taken care of by the authors' descendants. Even after surviving a long time, many of these personal records remain in the form of manuscripts, written in semi-cursive and cursive scripts of Chinese characters, thus making it even more difficult for the people of the current generation -- most of whom have not been given an opportunity to learn Chinese characters at school -- to take care of their documentary heritage properly. Meanwhile, it is also true that, as the value of the public records published by the government of Joseon as historical materials has grown, they are used more often as content for TV dramas such as Daejanggeum. At the same time, there have been increasingly louder voices citing the need for the study, preservation, and management of the personal diaries from Joseon. Considering the situation, this study provides a general overview of the personal diaries of Joseon as recently surveyed by the National Research Institute of Cultural Heritage, as well as their characteristic features, subjects, and backgrounds. This study is expected to contribute to future research on the preservation and management of the personal diaries of Joseon.

• Resources Recycling
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• v.17 no.6
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• pp.68-78
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• 2008

Using a Pinus koraiensis and Pinus rigida which are normally being discarded in South Korea, optimal conditions of producing activated carbons have been studied to recycle as a higher value-added product. This study consists of two processes, the production process of charcoals from waste timbers by low temperature pyrolysis and the production process of activated carbons from the charcoals by chemical activation reaction. This paper deals with the production process of activated carbons from the charcoals by chemical activation reaction. As an alkali has been generally used as an activating agent, KOH and NaOH which react well with a carbon were used in this study. As a result of the experiments, it is confirmed that activated carbons made with KOH treatment had superior values in physicochemical properties to NaOH, showing that there was no remain of KOH at the surface of the charcoals while there was $3{\sim}4%$ of NaOH remaining after the experiments. Thus, it is concluded that KOH reacted more actively with a charcoal than NaOH. Moreover, it was also found that values in physicochemical properties when using a Pinus koraiensis are superior to the ones when using a Pinus rigida. The optimal mixing ratio of an activating agent to a charcoal was 400 wt.%. To improve the physicochemical properties, activated carbons were washed out by distilled water after neutralization with SM hydrochloric acid solution. When activated carbons were produced from a Pinus koraiensis in this optimal conditions, value of BET surface area was found to be approx. $2400\;m^2/g$.

• Journal of Digital Convergence
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• v.10 no.9
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• pp.195-212
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• 2012

Most of the office-workers are worrying about their future and try to make diverse future plan. Fast shifting industry pattern make office-workers retire early and their remain life time are getting longer and many of them try to consider some kind of new start-up. In this article factors affecting entrepreneurial intention were discussed such as individual factors, psychological factors, environmental factors. Individual factors were economic situations and future life expectation were analyzed. Psychological factors were composed of risk taking tendency, self efficiency, career value, and entrepreneurial characteristics were discussed. Environmental factors were composed of recognition on social-economic risks and recognition on negative mind on start-up, and employment unstability. 340 sample questionaries were collected and 26 samples were excluded. Data were analyzed by SPSS Win 18.0 Version. The results of the study were as follows. Among individual factors life-expectation after retirement was positive impact on entrepreneurial intention. Among psychological factors risk taking factor has positive impact on entrepreneurial intention. Among Environmental factors negative recognition on start-up has negative impact on entrepreneurial intention. Based on the studies diverse understanding and implementation of policies were necessary to change negative social atmospheres on start-up.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.397-404
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• 2009

For standardization of LMK02 quality, Ginsenoside Rg3 of Red Ginseng and Decursin of Angelica gigas Nakai in the constituents of LMK02 were estimated as indicative components. From LMK02 water extract, has been used in vitro test for its beneficial effects on neuronal survival and neuroprotective functions, particularly in connection with APP-related dementias and Alzheimer's disease (AD). $A{\beta}$ oligomer derived from proteolytic processing of the ${\beta}$-amyloid precursor protein (APP), including the amyloid-${\beta}$ peptide ($A{\beta}$), play a critical role in the pathogenesis of Alzheimer's dementia. We determined that oligomer amyloid-${\beta}$ ($A{\beta}$) have a profound attenuation in the increase in rat hippocampus H19-7 cells from. Experimental evidence indicates that LMK02 protects against neuronal damage from cells, but its cellular and molecular mechanisms remain unknown. Using a hippocampus cell line on $A{\beta}$ oligomer-induced neuronal cytotoxicity, we demonstrated that LMK02 inhibits formation of $A{\beta}$ oligomer, which are the behavior, and possibly causative, feature of AD. In the Red Ginseng, the average amounts of Ginsenoside Rg3 were $47.04{\mu}g/g$ and $42.3{\mu}g/g$, 90 % of its weight were set as a standard value. And, in the Angelica gigas Nakai, the average amounts of Decursin were 2.71 mg/g and 2.44mg/g, 90 % of its weight were also set as a standard value. The attenuated $A{\beta}$ oligomer in the presence of LMK02 was observed in the conditioned medium of this $A{\beta}$ oligomer-induced cells under in vitro. In the cells, LMK02 significantly activated antiapoptosis and decreased the production of ROS. These results suggest that neuronal damage in AD might be due to two factors: a direct $A{\beta}$ oligomer toxicity and multiple cellular and molecular neuroprotective mechanisms, including attenuation of apoptosis and direct inhibition of $A{\beta}$ oligomer, underlie the neuroprotective effects of LMK02 treatment.

• Journal of Gifted/Talented Education
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• v.25 no.4
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• pp.547-563
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• 2015

This paper aims at figuring out specific characteristics of affective attitude of gifted and talented in information, predicting follow-up activities and desirable direction of learning. Based on the analysis of this paper as educational directions and suggestions for elementary gifted and talented students in information are as follows: First, in gender ratio of gifted and talented in information, including the fact that ratio of boys is high, there remain the previous prejudice of higher information capability and it seems that girls who depend on external factors, parents and teachers should make more efforts to help girls trust their own capability in information science and lead them to give more value to attribution of efforts for achievement in information science. Second, as grade is higher, motivation to learn information science and attitude for success in information science among sub-elements of attitude to information science, motivation to seed positive recognition to higher graders is required. Third, in screening and selecting gifted and talented students in information, attitude to information science should be considered as main cause and the existing gifted and talented students in information should be prompted to improve their attitude to information science with value on effort for information science.