• Structural Engineering and Mechanics
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• v.71 no.2
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• pp.131-138
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• 2019

It is necessary to predict subway induced vibration if a new subway is to be built. To obtain the vibration response reliably, a three-dimensional (3D) FEM model, consisting of the tunnel, the soil, the subway load and the building above, is established in MIDAS GTS NX. For this study, it is a six-story frame structure built above line 3 of Guangzhou metro. The entire modeling process is described in detail, including the simplification of the carriage load and the determination of model parameters. Vibration measurements have been performed on the site of the building and the model is verified with the collected data. The predicted and measured vibration response are used together to assess vibration level due to the subway traffic in the building. The No.1 building can meet work and residence comfort requirement. This study demonstrates the applicability of the numerical train-tunnel-soil-structure model for the serviceability assessment of subway induced vibration and aims to provide practical references for engineering applications.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.41.1-41.1
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• 2018

We constrain cosmological parameters by combining three different power spectra measured from galaxy clustering, galaxy-galaxy lensing, and cosmic shear using the Deep Lens Survey (DLS). Two lens bins (centered at z~0.27 and 0.54) and two source bins (centered at z~0.64, and 1.1) containing more than one million galaxies are selected to measure the power spectra. We re-calibrate the initial photo-z estimation of the lens bins by matching with SHELS and PRIMUS and confirm its fidelity by measuring a cross-correlation between the bins. We also check the reliability of the lensing signals through the null tests, lens-source flipping and cross shear measurement. Residual systematic errors from photometric redshift and shear calibration uncertainties are marginalized over in the nested sampling during our parameter constraint process. For the flat LCDM model, we determine S_8=sigma_8(Omega_m/0.3)^0.5=0.832+-0.028, which is in great agreement with the Planck data. We also verify that the two independent constraints from the cosmic shear and the galaxy clustering+galaxy-galaxy lensing measurements are consistent with each other. To address baryonic feedback effects on small scales, we marginalize over a baryonic feedback parameter, which we are able to constrain with the DLS data alone and more tightly when combined with Planck data. The constrained value hints at the possibility that the AGN feedback in the current OWLS simulations might not be strong enough.

• Journal of Information Technology Services
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• v.18 no.1
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• pp.91-112
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• 2019

The IoT environment has led to explosive growth of existing enterprise data, and how to utilize such big data is becoming an important issue in the management field. In this paper, major factors affecting the decisions of companies to utilize big data have been studied. And also, the effect of big data utilization on the management quality is studied empirically. During this process, we have studied the difference according to the award of Korean national quality award. As a result of the study, we confirmed that the five factors such as cost from technology, organization and environment perspective, compatibility, company size, chief officer support, and competitor pressure are key factors influencing big data utilization. Also, it was confirmed that the use of big data for management activities has an important influence on the six management quality factors based on MBNQA, and that the management quality level of Korean national quality award companies is relatively high. This paper provides practical implications for companies' use of big data because it demonstrates for the first time that big data utilization has an impact on management quality improvement.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.298-304
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• 2021

This study aimed to determine the applicability of drones and air quality sensors in environmental monitoring of air pollutant emissions by developing and testing two new methods. The first method used orthoimagery for precise monitoring of pollutant-emitting facilities. The second method used atmospheric sensors for monitoring air pollutants in emissions. Results showed that ground sample distance could be established within 5 cm during the creation of orthoimagery for monitoring emissions, which allowed for detailed examination of facilities with naked eyes. For air quality monitoring, drones were flown on a fixed course and measured the air quality in point units, thus enabling mapping of air quality through spatial analysis. Sensors that could measure various substances were used during this process. Data on particulate matter were compared with data from the National Air Pollution Measurement Network to determine its future potential to leverage. However, technical development and applications for environmental monitoring of pollution-emitting facilities are still in their early stages. They could be limited by meteorological conditions and sensitivity of the sensor technology. This research is expected to provide guidelines for environmental monitoring of pollutant-emitting facilities using drones.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.154-168
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• 2021

The purpose of this study is to develop and validate the disaster safety awareness scale for high school students. For this purpose, the previously developed disaster safety awareness scale and related prior research was analyzed. Questionnaire data was collected from March 22 to May 25, 2021 from 1054 students (male: 569, female: 485) in the first, second, and third grades of 5 high schools in 3 cities. Through the process of revising, supplementing, and reviewing the items extracted through preliminary research and preliminary test together with experts and students, a final disaster safety awareness scale consisting of 24 items was developed. This scale consists of four sub-factors: 'disaster prevention', 'disaster response A', 'disaster response B', and 'disaster recovery'. Good reliability and validity were secured through exploratory and confirmatory analyses. The significance of this study is that it laid a basic and objective foundation for high school students' disaster safety awareness research by developing a validated scale in a situation where the development of disaster safety awareness scales for high school students was still insufficient. It can be used as useful data for fire safety education as well as a psychological measurement tool for fostering fire safety awareness.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.134-142
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• 2021

This paper proposes a probabilistic method in analyzing timing measurements to determine the periodicity of real-time tasks. The proposed method fills a gap in existing techniques, which either concentrate on the estimation of worst-case execution times, or do not consider the stochastic behavior of the real-time scheduler. Our method is based on the Z-test statistical analysis which calculates the probability of the measured period to fall within a user-defined standard deviation limit. The distribution of the measured period should satisfy two conditions: its center (statistical mean) should be equal to the scheduled period of the real-time task, and that it should be symmetrical with most of the samples focused on the center. To ensure that these requirements are met, a data adjustment process, which omits any outliers in the expense of accuracy, is presented. Then, the Z-score of the distribution according to the user-defined deviation limit provides a probability which determines the periodicity of the real-time task. Experiments are conducted to analyze the timing measurements of real-time tasks based on real-time Linux extensions of Xenomai and RT-Preempt. The results indicate that the proposed method is able to provide easier interpretation of the periodicity of real-time tasks which are valuable especially in comparing the performance of various real-time systems.

• Journal of Drive and Control
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• v.18 no.1
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• pp.9-16
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• 2021

Overloaded vehicles increase the maintenance cost of road structures, and they are a major factor in causing damage to the roads and bridges. In addition, overloaded vehicles compromise the braking capability of the vehicle; thus, threatening the safety of the driver. In order to prevent overloading of vehicles, the government is cracking down on the roads by using a device that measures the weight of vehicles. But this process is inconvenient because the place where the equipment is installed is far away from where the cargo is loaded. Due to the limitations of these fixed weighing devices, there is a growing need for technology that can monitor vehicle weight distribution and overload conditions in real time. In this work, we develop an onboard scale that can measure the load (weight) of trucks in real time. The onboard scale consists of high sensors, a signal processing unit, and a display, and it measures the load using height-displacement of the vehicle's leaf spring suspension.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.479-486
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• 2021

This study aims to explore the relationships between strategic planning, strategic maneuverability, and firm performance in the current dynamic business environment. It employs a quantitative research method and reports on a survey, using a questionnaire, of service companies in Indonesia's oil and gas industry. Of the 337 companies selected by simple random sampling from a vendor database, responses were received from 70 companies. The analysis was performed using Partial Least Square Structural Equation Modeling and SmartPLS software. The analysis consisted of descriptive statistics, evaluation of the measurement model, evaluation of the structural model, and hypotheses testing. The results show that both strategic planning and strategic maneuverability have a positive relationship with firm performance. In addition, there is a positive relationship between strategic planning and firm performance through the mediating role of strategic maneuverability. The findings suggest that the organizational agility, organizational flexibility, and organizational responsiveness that constitute strategic maneuverability have a positive direct and indirect effect on firm performance, namely financial performance, customer performance, internal process performance, and learning and growth. This study contributes to the strategic management literature and the theory of maneuvers by providing empirical evidence on the relationship between strategic planning, strategic maneuverability, and firm performance.

• Journal of Distribution Science
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• v.19 no.2
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• pp.37-44
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• 2021

Purpose: O2O (Online to Offline) is an internet-based platform. The purpose of this study is to confirm the effect of service quality of O2O food delivery service on service satisfaction, and whether customer orientation mediates the relationship between service quality and service satisfaction. Research design, data and methodology: This paper surveyed Chinese consumers using the O2O food delivery platform through a questionnaire technique. Smart PLS 3.0 was used to verify the hypothesis of this study. PLS is characterized by the advantage of minimizing measurement errors and maximizing the influence of each factor. Results: It was confirmed that O2O food delivery companies need to increase service quality (information quality, product quality, and social quality, system quality) in order to obtain customer satisfaction. Additionally, the perceived customer orientation was found to completely mediate the relationship between perceived service quality (information quality, product quality) and perceived service satisfaction. Conclusions: The service level of the O2O delivery company to the customer's request when a problem occurs in the customer's order must be raised to increase the customer's satisfaction. For example, timely response to customer inquiries and timely feedback of delivery information to customers during the delivery process should improve the quality of after-sales service.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.413-421
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• 2021

This research empirically analyzed whether the foods which came from a non-Muslim majority country, such as South Korea, could play an important role in affecting the consumer intention in a predominantly Muslim country. Online survey methods were used to investigate the proposed hypothesis. 318 responses were used for further analysis. Forty-six reflective constructs were adapted from literature and designed by using a five-point Likert scale to facilitate measurement. Estimation models and structural models were examined through SEM-PLS analysis techniques using SmartPLS 3.0 application as the data processing tool. The results showed that religiosity and halal awareness had a positive and significant effect on attitude toward halal labels, including the mediating effect from consumer attitudes towards halal labels which had a positive but insignificant effect on purchase intention. Halal awareness plays an important role for Muslims in the decision-making process for purchasing food. In contrast to the initial hypothesis, the country of origin actually did not have a positive effect on attitudes towards the halal label. In a Muslim-majority country like Indonesia, findings halal food is not difficult, so this research basically is a reminder to marketers to follow those halal principles in implementing their marketing strategies.