• Journal of the Korean Association of Geographic Information Studies
• /
• v.26 no.3
• /
• pp.85-96
• /
• 2023

This study developed and evaluated a safe route guidance service for electric personal assistive mobility device used mainly by the mobility impaired people to improve their mobility. Thirteen underlying factors affecting the mobility of electric personal assistive mobility device have been derived through a survey with the mobility impaired people and employees in related organizations in Busan Metropolitan City. After assigning safety scores to individual factors and identifying the relevant factors along routes of interest with an object detection AI model, the safe route for electric personal assistive mobility device was provided through an optimal path-finding algorithm. As a result of comparing the general route of T-map and the recommended route of this study for the identical routes, the latter had relatively fewer obstacles and the gentler slope than the former, implicating that the recommended route is safer than the general one. As future works, it is necessary to enhance the function of a route guidance service based on the real-time location of users and to conduct spot investigations to evaluate and verify its social acceptability.

• Journal of Korea Water Resources Association
• /
• v.56 no.9
• /
• pp.529-541
• /
• 2023

Due to the growing concern over forecasting extreme weather events such as droughts caused by climate change, there has been a rising interest in seasonal meteorological forecasts that offer ensemble predictions for the upcoming seven months. Nonetheless, limited research has been conducted in South Korea, particularly in assessing their effectiveness at the catchment-scale. In this study, we assessed the accuracy of ECMWF's seasonal forecasts (including precipitation, temperature, and evapotranspiration) for the period of 2011 to 2020. We focused on 12 multi-purpose reservoir catchments and compared the forecasts to climatology data. Continuous Ranked Probability Skill Score method is adopted to assess the forecast skill, and the linear scaling method was applied to evaluate its impact. The results showed that while the seasonal meteorological forecasts have similar skill to climatology for one month ahead, the skill decreased significantly as the forecast lead time increased. Compared to the climatology, better results were obtained in the Wet season than the Dry season. In particular, during the Wet seasons of the dry years (2015, 2017), the seasonal meteorological forecasts showed the highest skill for all lead times.

• Journal of Navigation and Port Research
• /
• v.47 no.4
• /
• pp.256-270
• /
• 2023

In this study, a sliding mode (SM) controller for dynamic positioning (DP) was specifically designed for a turret connection operation of a ship or an offshore structure in which an arbitrary point on the structure could be controlled as the motion center instead of the center of mass. The SM controller allows control of the arbitrary point and provides capability to manage uncertainties in the dynamics of ships and offshore structures, external forces caused by unknown changing marine environments, and transient performance of DP systems. The Jacobian matrix included in kinematic equations of the controlled object was modified to design the SM controller to control based on an arbitrary point of ships or offshore structures. To ensure robustness of the controller, the Lyapunov stability theory was applied in the design of the SM controller. In general, for robustness in DP control, gain scheduling based on a proportional-derivative (PD) control algorithm is employed. However, finding appropriate gains for gain scheduling complicates the application of DP systems. Therefore, in this study, the SM control algorithm was considered to mitigate the complexity of the DP controller for ships and offshore structures. To validate the proposed SM control algorithm, time-domain simulations were conducted and utilized to evaluate the performance of the control algorithm. The effectiveness of the proposed SM controller was assessed by comparing simulation results with results of a conventional PD control algorithm applied in DP control.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.33 no.2
• /
• pp.295-303
• /
• 2023

As the cloud computing market grows, a variety of cloud services are now reliably delivered. Administrative agencies and public institutions of South Korea are transferring all their information systems to cloud systems. It is essential to develop security solutions in advance in order to safely operate cloud services, as protecting cloud services from misuse and malicious access by insiders and outsiders over the Internet is challenging. In this paper, we propose a zero trust model for cloud storage services that store sensitive data. We then verify the effectiveness of the proposed model by operating a cloud storage service. Memory, web, and network forensics are also performed to track access and usage of cloud users depending on the adoption of the zero trust model. As a cloud storage service, we use Amazon S3(Simple Storage Service) and deploy zero trust techniques such as access control lists and key management systems. In order to consider the different types of access to S3, furthermore, we generate service requests inside and outside AWS(Amazon Web Services) and then analyze the results of the zero trust techniques depending on the location of the service request.

• Journal of Service Research and Studies
• /
• v.13 no.2
• /
• pp.161-180
• /
• 2023

This study empirically analyzed the effect of perceived injustice on service recovery measures proposed by online food delivery service (OFDS) companies on consumer disappointment. This study adopted interaction justice, information justice, procedural justice, and distributive justice as sub-variables of justice perception based on the justice theory. In addition, the differences by generation (MZ generation and other generations) were examined in the relationship between negative word-of-mouth behavior and switching intentions due to service recovery failure. An online survey was conducted targeting 250 adult consumers in the U.S for the empirical analysis of this research model. The results of the data analysis demonstrated that negative perceptions about the procedural justice and distributive justice among the service recovery strategies had a positive effect upon the consumer's disappointment. Furthermore, it was confirmed that the consumer's disappointment due to the perceived injustice of the service recovery strategy had a positive effect on the consumer's negative word-of-mouth behavior and switching intentions. The verification results of the moderation effect in the relationship between negative word-of-mouth behavior and switching intention, it was found that the younger the age(MZ generation), the higher the possibility of causing dysfunctional behavior. This study expands the scope of related research by presenting a new perspective on the justice perception in the service recovery process by verifying dysfunctional behavior of consumers caused due to the failure of the service recovery strategy. It is believed that the results of this study will be used as basic data for the establishment of practical strategies for OFDS companies to prevent double defection of their customers.

• Journal of Convergence for Information Technology
• /
• v.12 no.3
• /
• pp.132-140
• /
• 2022

This study was conducted to identify the optimal lotion manufacturing conditions with decursin and decursinol angelate of Angelica gigas Nakai extraction. Lotion was confirmed that it had viscosity (5,208±112 cPs), assay (99.71±1.01%), and pH (5.62) for 3 months. The optimization of manufacturing conditions of mixing 4 for lotion formulation were made by 22+3 full factorial design. Mixing temperature (40-80℃) and mixing time (10-30 min) were used as independent variables with three responses(assay, pH, and weight variation) as critical quality attributes (CQAs). The model for assay and weight variation identified a proper fit having a determination coefficient of the regression equation (about 0.9) and a p-value less than 0.05. Estimated conditions for the optimal manufacturing process of lotion were 61.93℃ in mixing temperature and 15.85 min in mixing time. Predicted values at the mixing temperature (60℃) and mixing time (20 min) were 100.69% of assay, 5.57 of pH, and 98.07% of weight variation. In the verification of the actual measurement the obtained values showed 100.29±0.98% of assay, 5.57±0.02 of pH, and 98.27±0.89% of weight variation, respectively, in good agreement with predicted values.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.7 no.6
• /
• pp.701-708
• /
• 2017

The construction cost is estimated based on the drawings at the design stage and constructor will find efficient construction methods for budgeting and budgeting appropriate to the budget. Accurate quantity estimation and budgeting are critical to determining whether the project is profitable or not. However, since this process is mostly performed depending on manpower or 2D drawings, errors are likely to occur and The BIM(Build Information Modeling) program, which can be automated, is very expensive and difficult to apply in the field. In this study, 3D architectural modeling was performed using SketchUp which is a 3D modeling software and suggest a methodology for Quantity Estimation. As a result, 3D modeling was performed effectively using 2D drawings of buildings. Based on the modeling results, it was possible to calculate the difference of the quantity estimation by 2D drawing and 3D modeling. The research suggests that the 3D modeling using the SketchUp and the calculation of the quantity can prevent the error of the conventional 2D calculation method. If the applicability of the research method is verified through continuous research, it will contribute to increase the efficiency of architectural modeling and quantity Estimation work.

• 한국노년학
• /
• v.29 no.3
• /
• pp.917-933
• /
• 2009

This study examined the factors affecting forms of long-term care service use by elderly and the forms of use are classified facility care service, home care service, and unused. It is used data from the 2nd pilot program for the Long Term Care Insurance scheme and it is analysed 5,497 cases. Multi-nominal regression is used. According to the results, women use formal service more than man do, and wowen use facility care than home care. Those who eligible for National Basic Livelihood Security System(NBLSS) are shown to have higher use of formal care(especially facility care) than the middle income class, and the low income class than the middle income class has lower use of formal care. In addition, higher the family care is available, lower the taking part in the service. The big cities and mid sized cities than rural are used the formal service and moreover mid sized cities are used facility care than home care. Furthermore, the level of care need is determinants of service use and function of ADL, IADL, and abnormal behavior is also determinants of formal service(especially facility care). But nursing need and rehabilitation need are not determinants of formal service use. Based on the results, the recommendations are developed and implemented for the improvement the elderly long-term care insurance.

• Journal of Venture Innovation
• /
• v.6 no.3
• /
• pp.73-93
• /
• 2023

This study provides a prospect for the fast growing the smartwatch market by investigating the relationship between the satisfaction and the continuous use intention of Apple watch users, as well as the factors influencing their satisfaction. Based on the TAM, this study uses system quality, information quality, and self-efficacy as independent variables, perceived usefulness, perceived ease of use, and satisfaction as mediators, and continuous use intention as the dependent variable. We analyze the data of 256 individuals who completed an online survey with SPSS 26.0 and AMOS 26.0 software. This study conducts several tests and analyses to empirically evaluate the data including reliability analysis, factor analysis, feasibility analysis, path analysis, hypothesis verification, and mediation analysis. Our results investigate which factors may influence consumers' intention to continuously using Apple Watch devices in the future. In summary, satisfaction has a positive effect on the intention to continuously use smartwatchs. Perceived usefulness and perceived ease of use have a positive effect on satisfaction. Among the three factors (system quality, information quality, and self-efficacy), only self-efficacy has no significant impact on perceived usefulness but had a positive effect on perceived ease of use. In addition, system quality and information quality positively affect perceived usefulness, perceived ease of use, satisfaction, and continuous intention to use an Apple Watch. Taking the Apple Watch as the subject of our research topic, this study provides theoretical value by exploring the impact of user's satisfaction with their smartwatch on their continuous usage intention. This study further explains the influence of system quality, information quality, and self-efficacy on user satisfaction. Additionally, this research offers valuable insight to practitioners by confirming that information quality, system quality, and self-efficacy are important features for enhancing satisfactory user experiences which in turn may increase users' intention to continued using smartwatches.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.17 no.1
• /
• pp.139-155
• /
• 2022

This paper presented a research model to investigate the relationship between the psychological traits of small business entrepreneurs and entrepreneurial orientation and the relationship between entrepreneurial orientation and performance. To verify the research model, a total of 202 entrepreneurs in Daegu were surveyed and the data obtained were used. The collected data were analyzed by SPSS and AMOS. The results of the analysis showed that all of the psychological traits except 'Agreeableness' and 'Extroversion' among the small business entrepreneur's psychological trait had a positive(+) effect on entrepreneurial orientation. In addition, it was confirmed that entrepreneurship orientation had a positive(+) effect on performance, and government policy funding had a moderating effect between entrepreneurship orientation and performance. In conclusion, the causal relationship between the small business entrepreneur's psychological traits and entrepreneurial orientation is examined, and the moderating effect of government support programs is examined to find out what psychological traits of small business entrepreneurs affect the expression of entrepreneurial orientation. In addition, since entrepreneurial orientation affects performance and government policy funds control, it suggests that continuous financial support for small business entrepreneurs is needed.