• Information Systems Review
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• v.24 no.1
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• pp.125-155
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• 2022

Platform contrasts with traditional industry in terms of innovativeness as it is rapidly developing with information technology. To redeem preceding researches which have separately focused on either platform acceptance based on technology acceptance model or resistance factors against platform's innovation, this study applied dual factor theory to check the simultaneous influence of enablers and inhibitors on resistance. This study chose purchasers of online used trading platform as a subject of study since it contrasts with other platforms in many characteristics. Based on preceding studies, the moderating effects of their past purchase numbers on the relations between resistance and use intention were also checked. The findings reveal that economic benefit as an enabler had significant negative influence on the resistance, but social influence didn't have expected influence. In case of inhibitors, both perceived complexity and perceived risk had significant positive influence on the resistance. Though resistance had significant negative influence on the use intention, its influence was moderated into the positive direction as users' purchase number increased. Lastly, resistance had mediation effect between antecedent factors (economic benefit and perceived complexity) and use intention.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.318-326
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• 2023

The floristic target species (FTS) has been widely used as a important tool for environmental assessment in Korea. Here the floristic district is a key criterion for the selection and evaluation of FTS. The aim of this study is to clarify the intellectual meaning of the floristic district i.e. a sort of phytogeographical subunit. We reviewed 7 main literatures related to the floristic district. Nakai's 1919 Ulleungdo flora survey report was first to mention a region and/or province in terms of general geographical divisions. In 1977, the floristic district map of the Korea vascular plants was first described by Oh. In 1978, Lee & Yim proposed a new floristic district map dividing the central and southern regions, and the district boundaries have been adjusted by many other researchers. In the end, the floristic district map modified slightly from Lee & Yim's map was nationally recognized in 2018. However, the boundaries of floristic districts were inconsistent, both in their setting and adjustment, as well as the indicator species of the district. No basis for this inconsistency could be confirmed. We concluded that all district maps depend on arbitrary lines drawn a priori, and finally proposed the following two ecological strategies to ensure the effectiveness and practicality of the FTS as a scientific means for environmental impact assessment and national flora evaluation: (i) designing to achieve the flora list and the floristic district based on nativeness of plant distribution, (ii) constructing a habitat-based floral monitoring system.

• Korean Chemical Engineering Research
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• v.62 no.2
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• pp.163-172
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• 2024

In this study, two different scenarios for ammonia liquefaction in the green ammonia manufacturing process were proposed, and the economic-feasibility and environmental impact of each scenario were analyzed. The two liquefaction processes involved gas-liquid separation before cooling at high pressure (high pressure cooling process) or after decompression without the gas-liquid separation (low pressure cooling process). The high-pressure cooling process requires higher capital costs due to the required installation of separation units and heat exchangers, but it offers relatively lower total utility costs of 91.03 $/hr and a reduced duty of 2.81 Gcal/hr. In contrast, although the low-pressure cooling process is simpler and cost-effective, it may encounter operational instability due to rapid pressure drops in the system. Environmental impact assessment revealed that the high-pressure cooling process is more environmentally friendly than the low-pressure cooling process, with an emission factor of 0.83 tCO₂eq less than the low-pressure cooling process, calculated based on power usage. Consequently, the outcomes of this study provide relevant scenario and a database for green ammonia synthesis process adaptable to various process conditions.

• Korean Chemical Engineering Research
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• v.62 no.2
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• pp.147-152
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• 2024

Most medical sensors are disposable products. In order to reduce inspection and diagnosis costs, it is more important to develop the inexpensive electrode materials. We fabricated the CuO NPs/PANI/E-PGE as an electrode material for disposable electrochemical sensors and applied it to a non-enzymatic glucose sensor. For surface activation of PGE, pretreatment was performed using chemical and electrochemical methods, respectively. Electrochemical properties according to the pretreatment method were analyzed through chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance (EIS). From these analytical results, the electrochemically pretreated PGE (E-PGE) was finally adopted. The non-enzymatic glucose sensor based on CuO NPs/PANI/E-PGE shows sensitivity of 239.18 mA/mM×cm² (in a linear range of 0.282~2.112 mM) and 36.99 mA/mM×cm² (3.75423~50 mM), detection limit of 17.6 μM and good selectivity. Based on the results of this study, it was confirmed that the modified PGE is a high-performance electrode material. Therefore, these electrodes can be applied to a variety of disposable sensors.

• Journal of the Korean GEO-environmental Society
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• v.25 no.5
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• pp.29-37
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• 2024

This study aimed to investigate the changes in chemical components that occur when weak clay is mixed with steel slag modified with calcium oxide, and to understand the expression characteristics of compressive strength according to hydrophilicity and curing time. XRF testing, SEM imaging, vane shear strength and uniaxial compressive strength testing were conducted. Calcium (Ca) released from the steel slag increases the Ca content in clay by increasing the number of crystal particles and forming a coating layer known as calcium silicate hydrate (CaO-SiO₂-H₂O) through chemical reactions with SiO₂ and Al₂O₃ components. The weak clay stabilized with steel slag is classified into an initial inactive zone where strength relatively does not increase and an activation zone where strength increases over curing time. The vane shear strength of the initial inactive area was found to be 4.4 to 18.4 kN/m² in the state of the weight mixing ratio Rss 30% (steel slag 30% + clay 70%). In the case of the active area, the maximum uniaxial compressive strength increased to 431.8 kN/m² after 480 hours of curing time, which increased due to the apparent adhesion strength of clay through pozzolanic reaction. Therefore, considering the strength expression characteristics of stabilized mixed clay based on the mixing ratio (Rss) during the recycling of steel slag can enhance its practicality in civil engineering sites.

• Land and Housing Review
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• v.15 no.1
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• pp.167-177
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• 2024

This study aimed to assess the efficacy of an adsorption process in removing organic matter and micropollutant residuals. After a full-scale water circulation system, the adsorption process was considered a post-treatment step. The system, treating anthropogenically impacted surface waters, comprises a hydro-cyclone, coagulation, flocculation, and dissolved air flotation unit. While the system generally maintained stable and satisfactory effluent quality standards over months, it did not meet the highest standard for organic matter (as determined by chemical oxygen demands). Adsorption experiments utilized two granular activated carbon types, GAC 830 and GCN 830, derived from coal and coconut-shell feedstocks, respectively. The assessment encompassed organic materials along with two notable micropollutants: acetaminophen (APAP) and acid orange 7 (AO7). Adsorption kinetics and isotherm experiments were conducted to determine adsorption rates and maximum adsorption amounts. The quantitative findings derived from pseudo-second-order kinetics and Langmuir isotherm models suggest the effectiveness of the adsorption process. The findings of this study propose the potential of employing the adsorption process as a post-treatment to enhance the treatment of contaminants that are not satisfactorily treated by conventional water circulation systems. This enhancement is crucial for ensuring the sustainability of urban water cycles.

• Korean Journal of Heritage: History & Science
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• v.57 no.2
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• pp.28-50
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• 2024

A fact-finding survey of the Demilitarized Zone can be said to be a very meaningful academic survey linked to previous index surveys of protected military areas and municipal and excavation surveys of ruins and military sites on Mount Dora. Not a few ruins were first discovered in this survey, and the locations, structures, and restoration artifacts of the previously investigated ruins were confirmed differently, raising the need for a detailed investigation. In particular, it is noteworthy that various relics from the Paleolithic Age to the Joseon Dynasty were recovered from relics dispersion sites such as Josan-ri and Cheorwon Gangseo-ri in Paju, and Hoengsan-ri Temple Site is also a Buddhist relic in the Demilitarized Zone. However, in the case of some graveyards and relics sites in the Paju region, it was an opportunity to understand the reality that they are not safe from cultivation and development, and the ruins of Cheorwon Capital Castle, Seongsanseong Fortress, Jorangjin Bastion, and Gangseo-ri Bastion were damaged during the construction of military facilities, and an urgent investigation is needed. Also, farmland and hilly areas around the ruins of Jangdan, Gunnae-myeon, and Gangsan-ri have not been properly investigated for buried cultural assets due to small-scale development. Therefore, it is an important time for the relevant authorities and agencies to cooperate more closely to establish special management and medium- to long-term investigation measures for the cultural heritage in the Demilitarized Zone based on the results of this fact-finding investigation.

• Korean Journal of Heritage: History & Science
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• v.57 no.2
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• pp.52-78
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• 2024

This study analyzes the sculptural art of SeokhaSichan(石霞施讚, 1893-1958), a significant figure in modern Korean Buddhist art, to re-examine his contributions and standing in the history of Korean Buddhist art. Sichan expanded the boundaries of modern Korean Buddhist art by developing a unique style based on the traditional sculptural techniques he learned from his mentor, Wanho Nakhyeon (玩虎洛現, 1869~1933). This study explores Sichan's artistic development, focusing on his artistic characteristics and sculptural evolution. Sichan's early works are characterized by small sculptures modeled after the main Buddha of Seokguram Grotto and heavily influenced by his mentor, WanhoNakhyeon. In his later works, notable features include a sense of massive volume, larger scale, upright postures, integration of the Buddha statue with its pedestal, and decorative treatment of drapery. These changes are interpreted as Sichan's response to social changes and his reflection of inner contemplation and artistic exploration in his works. This study reveals the influences of Wanho Nakhyeon, collaborations with Toewon Woneil(退雲圓日, 1877~1939), interactions with patron Kim Jiseonghwa(金至誠華), and master-disciple relationship with successor Geumchun Seongpil(金春性必) through literature review and newly discovered works by Sichan. His works and his artistic evolution are pivotal milestones in the history of modern Korean Buddhist sculpture, demonstrating a unique integration of traditional and modern aesthetics. This study provides valuable insights into how Sichan's artistic legacy was inherited and developed by subsequent generations and offers crucial materials for the study of modern Korean Buddhist sculpture history.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1918-1928
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• 2021

Objective: With the recent development of various MRI-conditional cardiac implantable electronic devices (CIEDs), the accurate identification and characterization of CIEDs have become critical when performing MRI in patients with CIEDs. We aimed to develop and evaluate a deep learning-based algorithm (DLA) that performs the detection and characterization of parameters, including MRI safety, of CIEDs on chest radiograph (CR) in a single step and compare its performance with other related algorithms that were recently developed. Materials and Methods: We developed a DLA (X-ray CIED identification [XCID]) using 9912 CRs of 958 patients with 968 CIEDs comprising 26 model groups from 4 manufacturers obtained between 2014 and 2019 from one hospital. The performance of XCID was tested with an external dataset consisting of 2122 CRs obtained from a different hospital and compared with the performance of two other related algorithms recently reported, including PacemakerID (PID) and Pacemaker identification with neural networks (PPMnn). Results: The overall accuracies of XCID for the manufacturer classification, model group identification, and MRI safety characterization using the internal test dataset were 99.7% (992/995), 97.2% (967/995), and 98.9% (984/995), respectively. These were 95.8% (2033/2122), 85.4% (1813/2122), and 92.2% (1956/2122), respectively, with the external test dataset. In the comparative study, the accuracy for the manufacturer classification was 95.0% (152/160) for XCID and 91.3% for PPMnn (146/160), which was significantly higher than that for PID (80.0%,128/160; p < 0.001 for both). XCID demonstrated a higher accuracy (88.1%; 141/160) than PPMnn (80.0%; 128/160) in identifying model groups (p < 0.001). Conclusion: The remarkable and consistent performance of XCID suggests its applicability for detection, manufacturer and model identification, as well as MRI safety characterization of CIED on CRs. Further studies are warranted to guarantee the safe use of XCID in clinical practice.

• Health Policy and Management
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• v.34 no.2
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• pp.106-119
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• 2024

Drug shortage is a persistent phenomenon that poses a public health risk worldwide and occurs due to a range of causes. The purpose of this study is to review key policies to prepare for and respond to drug shortages in selected countries, such as the United States, Canada, and some European countries in order to draw implications. This study reviewed the reports and articles derived from search engines and Google Scholar by using keywords such as drug shortage and stock-out. Over the last decade or so, the United States have strengthened requirements on advance notification for disruption and interruption of drug manufacturing, established the Inter-agency Drug Shortages Task Force to promote the communication and coordination of responses, and expedited drug regulatory processes. Similarly, Canada established the Multi-Stakeholder Steering Committee on drug shortages by involving representatives from central and local governments and private sectors. Canada also adopted a tiered approach to the communication of drug shortages based on the assessment of the severity of the shortage problem and released a detailed information guide on communication. In 2019, the joint task force between the European Medicines Agency and the Heads of Medicines Agencies issued guidelines on drug shortage communication in the European Economic Area. The countries reviewed in this paper focus on communication across different stakeholders for the monitoring of and timely response to drug shortages. The efforts to protect public health from the negative impact of the drug shortage crisis would require multi-sectorial and multi-governmental coordination and development of guidelines.