• Journal of radiological science and technology
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• v.43 no.6
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• pp.481-487
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• 2020

Radiation measurement technology has steadily improved and its usage is expanding in various industries such as nuclear medicine, security search, satellite, nondestructive testing, environmental industries and the domain of nuclear power plants (NPPs). Especially, the simultaneous measurements of gamma rays and neutrons can be even more critical for nuclear safety management of spent nuclear fuel and monitoring of the nuclear material. A semiconductor detector comprising cadmium, zinc, and tellurium (CZT) enables to detect gamma-rays due to the significant atomic weight of the elements via immediate neutron and gamma-ray detection. Semiconductor sensors might be used for nuclear safety management by monitoring nuclear materials and spent nuclear fuel with high spatial resolution as well as providing real-time measurements. We aim to introduce a portable nuclide-analysis device that enables the simultaneous measurements of neutrons and gamma rays using a CZT sensor. The detector has a high density and wide energy band gap, and thus exhibits highly sensitive physical characteristics and characteristics are required for performing neutron and gamma-ray detection. Portable nuclide-analysis device is used on NPP-decommissioning sites or the purpose of nuclear nonproliferation, it will rapidly detect the nuclear material and provide radioactive-material information. Eventually, portable nuclide-analysis device can reduce measurement time and economic costs by providing a basis for rational decision making.

• Informatization Policy
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• v.28 no.4
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• pp.3-18
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• 2021

The 'digital divide' is regarded as a latent dysfunction that impedes the intrinsic role of information to contribute to social equality. Therefore, it has drawn great attention inside and outside of academia. The growing interest in the digital divide has been driven by the realization that it can create a serious crisis that threatens a social system compounded by existing economic, social, and cultural inequality, rather than being limited to an uneven distribution of information. In this paper (1) studies on the digital divide published since 1970 are reviewed, (2) studies noteworthy of discussion are selected to assess their academic significance, and (3) the tasks and prospects of digital divide research are explored. Although meaningful achievements have been amassed through continuous interest and efforts of the academic community, two limitations are raised; the gap between pure research and policy research that hinders the working of synthetic imagination, and the intellectual lag falling behind a rapidly changing society. In addition, it is suggested that the operation, curation, and augmentation gaps would emerge as new agenda for digital divide research in the intelligent information age.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.186-195
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• 2007

Key Performance Indicators (KPIs) are the criteria of measuring project performance in order to attain construction excellence. Previous researchers have examined the abstract concept of success for general new construction and identified its relationship with the factors of success. In fact, most buildings exist to satisfy the needs of people. With the passing of time and change in technology, buildings have to be maintained and renovated in order to continue functioning properly for the benefits of users. Therefore, criteria and factors of success have increasingly attracted the attention of both researchers and practitioners, especially in cities where buildings become ageing. However, the topic of project success for maintenance projects is less discussed in previous research, and project participants, including maintenance surveyors should be able to identify the success measurement and its associated factors for performance improvement. This study fills the research gap by investigating the criteria and factors of success for maintenance projects. It first provides a summary of the literature review on the criteria and factors of success for construction projects. An empirical study has also been carried out with ten practitioners in Hong Kong to further identify the criteria and factors critical for the success of maintenance projects in practice. While most criteria and factors of success for new construction projects are also applicable to maintenance projects, participants in maintenance projects believe that effective communication is in particular important to provide quality service to the end-users.

• Korean Journal of Environmental Agriculture
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• v.42 no.1
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• pp.21-27
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• 2023

Pre-harvest residue limits (PHRLs) have been proposed as criteria for a proactive role to exceed the maximum residue limit (MRL) of pesticides in agricultural products at harvest. However, PHRL numbers are significantly less than those of established MRLs. This study was performed to determine the dissipation constants and residual concentrations of lufenuron after application on crown daisy and chamnamul under green house conditions. Two residue field trials for each crown daisy and chamnamul were selected to consider a different geographical site at least 20 km far from one another. The pesticide was treated according to critical GAP. After samples were sprayed with lufenuron, they were collected at 0, 1, 3, 5, 7, 10, and 14 days and analyzed using HPLC-DAD. The mean recoveries of crown daisy and chamnamul were within the range of 70-120% with below 20% coefficient variation, which is within the acceptable limits specified by the manual of pre-harvest residue study for pesticides (MFDS, 2014). The biological half-lives in field I and field II were 7.0 and 4.6 days for crown daisy and 2.7 and 2.8 days for chamnamul, respectively. The lower bounds of 95% confidence intervals of dissipation rate constants of lufenuron in crown daisy were determined to be 0.0692 and 0.1298 for field I and field II, respectively, and in chamnamul were 0.2067 for both field I and field II. After applying lufenuron 5% EC, the lufenuron residues on crown daisy and chamnamul at the pre-harvest intervals (14 days for crown daisy and 7 days for chamnamul) were below the safe levels. The dissipation rates of lufenuron in crown daisy and chamnamul were evaluated for similarities with leafy vegetables based on a 95% confidence interval.

• Smart Structures and Systems
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• v.30 no.5
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• pp.479-500
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• 2022

In this study, a new type of isolation bearing is proposed by combining S-shaped steel plate dampers (SSDs) with a spherical steel bearing, and the seismic control effect of a five-span standard high-speed railway bridge is investigated. The advantages of the proposed S-shaped steel damping friction bearing (SSDFB) are that it cannot only lengthen the structural periods, dissipate the seismic energy, but also prevent bridge unseating due to the restraint effectiveness of SSDs in the large relative displacements between the girders and piers. This study first presents a detailed description and working principle of the SSDFB. Then, mechanical modeling of the SSDFB was derived to fundamentally define its cyclic behavior and obtain key mechanical parameters. The numerical model of the SSDFB's critical component SSD was verified by comparing it with the experimental results. After that, parameter studies of the dimensions and number of SSDs, the friction coefficient, and the gap length of the SSDFBs were conducted. Finally, the longitudinal seismic responses of the bridge with SSDFBs were compared with the bridge with spherical bearing and spherical bearing with strengthened shear keys. The results showed that the SSDFB can not only significantly mitigate the shear force responses and residual displacement in bridge substructures but also can effectively reduce girder displacement and prevent bridge unseating, at a cost of inelastic deformation of the SSDs, which is easy to replace. In conclusion, the SSDFB is expected to be a cost-effective option with both multi-stage energy dissipation and restraint capacity, making it particularly suitable for seismic isolation application to high-speed railway bridges.

• Korean Journal of Materials Research
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• v.33 no.9
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• pp.360-366
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• 2023

This study focuses on how the partial substitution of copper by nickel nanoparticles affects the electrical and structural properties of the Bi₂Ba₂Ca₂Cu_2.9Ni_0.1O_10+δ, Bi₂Ba₂Ca₂Cu_2.8Ni_0.2O_10+δ and Bi₂Ba₂Ca₂Cu_2.6Ni_0.4O_10+δ compounds. Approximate values of crystallization size and crystallization percentage for the three compounds were calculated using the Scherer, modified Scherer, and Williamson-Hall methods. A great similarity was observed in the crystal size values from the Scherer method, 243.442 nm, and the Williamson-Hall method, 243.794 nm for the second sample. At the same time this sample exhibited the highest crystal size value for the three methods. In the examination of electrical properties, the sample with 0.1 partial substitution, Bi₂Ba₂Ca₂Cu_2.9Ni_0.1O_10+δ was determined to be the best with a critical temperature of 100 K and an energy gap of 6.57639 × 10^-21 MeV. Using the SEM technique to analyze the structural morphology of the three phases, it was discovered that the size of the granular forms exceeds 25 nm. It was determined that the samples' shapes alter when nickel concentration rises. The patterns that reveal the distribution of the crystal structure also exhibit clear homogeneity.

• Journal of the Korean Regional Science Association
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• v.39 no.4
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• pp.19-32
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• 2023

Using extensive job posting big data, this study investigates the industrial and locational characteristics of decent work from the supply side. The analysis revealed that manufacturing is pivotal in supplying decent work, accompanied by a stark regional disparity, most notable in the Seoul Metropolitan Statistical Area (MSA), which constitutes nearly half of all decent work opportunities. The study further uncovered that the distribution of decent work varies significantly across MSAs, with a pronounced inclination towards a higher supply in peripheral rather than central areas. These findings bring to light the critical need for policies that bolster manufacturing, aiming to enhance the availability of high-quality jobs and to bridge the job quality gap between the Seoul MSA and other regions. Moreover, the results emphasize the necessity for customized job supply strategies in each MSA, prioritizing strategies that account for the proximity between workplaces and living areas in the job supply process.

• Journal of Veterinary Science
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• v.25 no.3
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• pp.38.1-38.16
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• 2024

Importance: Deaths due to neonatal calf diarrhea are still one of the most critical problems of cattle breeding worldwide. Determining the parameters that can predict diarrhea-related deaths in calves is especially important in terms of prognosis and treatment strategies for the disease. Objective: The primary purpose of this study was to determine mortality rates and durations, survival status, and predictive prognosis parameters based on vital signs, hematology, and blood gas analyses in neonatal diarrheic calves. Methods: The hospital automation system retrospectively obtained data from 89 neonatal diarrheic calves. Results: It was found that 42.7% (38/89) of the calves brought with the complaint of diarrhea died during hospitalization or after discharge. Short-term and long-term fatalities were a median of 9.25 hours and a median of 51.50 hours, respectively. When the data obtained from this study is evaluated, body temperature (℃), pH, base excess (mmol/L), and sodium bicarbonate (mmol/L) parameters were found to be lower, and hemoglobin (g/dL), hematocrit (%), lactate (mmol/L), chloride (mmol/L), sodium (mmol/L) and anion gap (mmol/L) parameters were found to be higher in dead calves compared to survivors. Accordingly, hypothermia, metabolic acidosis, and dehydration findings were seen as clinical conditions that should be considered. Logistic regression analysis showed that lactate (odds ratio, 1.429) and CI^- (odds ratio, 1.232) concentration were significant risk factors associated with death in calves with diarrhea. Conclusions and Relevance: According to the findings obtained from this study, the determination of lactate and Cl^- levels can be used as an adjunctive supplementary test in distinguishing calves with diarrhea with a good prognosis.

• The Mathematical Education
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• v.63 no.2
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• pp.273-294
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• 2024

Recently, interest in Edu-Tech, which applies new technologies to the educational field, is growing. Edu-Tech is now being naturally used in schools, allowing both teachers and students to adapt to these changes. Particularly, there's significant attention on using Edu-Tech to bridge the educational gap through various teaching and learning strategies. This study focuses on the importance of self-directed task management by students for supplementary learning. It developed and utilized a math learning platform that enables teachers to easily provide and manage necessary tasks for students. Initially, the study developed "Sussam-MathTeacher" a problem-based learning application for middle school students, aimed at enhancing problem-solving abilities. This platform operates as a task management system, allowing teachers to assign or recommend problems to either the entire class or individual students. It aims to improve students' problem-solving abilities through a process that includes presenting necessary tasks, monitoring their own progress in solving problems, and self-assessing growth. Through this study, students demonstrated improved problem-solving skills by tackling tasks suited to their levels using "Sussam" highlighting the critical role of teachers in the digital educational environment.

• Asia pacific journal of information systems
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• v.29 no.2
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• pp.308-327
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• 2019

The concept of sharing economy has received rich attention in recent years. As a typical type of business model in the sharing economy, online short rent has been paid attention by both industry and academia. In this study, we find trust to be a critical determinant to the success of online short rent platforms. Based on three dimensions of trust theory, i.e., ability, benevolence and integrity, we investigate the factors influencing tenant' willingness to participate in online short rent. We further examine the extent to which trust can influence the number of sales and comments of rooms listed at online short-term rent platforms, which can represent tenant' willingness to participate in the sharing economy. The results show that the trust dimensions represented by a landlord's personal characteristics have significant positive correlations with the number of sales and comments. For example, the real name authentication and the sesame score can represent the trust integrity; online replay ratio and the average confirmation time representing the trust sincerity, and the order acceptance ratio representing the trust ability. On this basis, we proposed some recommendations for both platforms and landlords. For example, the landlords can improve the tenants' trust by authenticating his/her real name, replying actively and timely. For platforms, when they make housing list ranking rules, they can take the landlord's personal attributes that may affect trust into consideration. Moreover, platforms can also allow landlords to supply value-added services to improve service quality and ultimately promote the virtuous circle of the platform ecosphere. Through conducting the empirical research on a particular application of the sharing economy, we aim to fill the research gap of this field in China and provide theoretical and practical contributions to the future development of online short rent.