• Smart Structures and Systems
• /
• v.5 no.1
• /
• pp.43-54
• /
• 2009

This study introduces a novel approach for locating damage in a structure using wireless sensor system with local level computational capability to alleviate data traffic load on the centralized computation. Smart wireless sensor systems, capable of iterative damage-searching, mimic an optimization process in a decentralized way. The proposed algorithm tries to detect damage in a structure by monitoring abnormal increases in strain measurements from a group of wireless sensors. Initially, this clustering technique provides a reasonably effective sensor placement within a structure. Sensor clustering also assigns a certain number of master sensors in each cluster so that they can constantly monitor the structural health of a structure. By adopting a voting system, a group of wireless sensors iteratively forages for a damage location as they can be activated as needed. Since all of the damage searching process occurs within a small group of wireless sensors, no global control or data traffic to a central system is required. Numerical simulation demonstrates that the newly developed searching algorithm implemented on wireless sensors successfully localizes stiffness damage in a plate through the local level reconfigurable function of smart sensors.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.37 no.1
• /
• pp.39-47
• /
• 2021

Compared to conventional method, if metal framework of removable partial denture is fabricated by selective laser melting, various laboratory works are omitted, saving time and simplifying the process. In addition, metal framework with homogeneous density can be obtained, expecting excellent mechanical properties, especially resistance to fatigue fracture. In these cases, impression were taken using conventional methods in partial edentulous patients, master casts were fabricated and scanned to obtain digital data. After designing the metal frameworks on the scanned data, removable partial dentures were fabricated using selective laser melting methods. Through these procedure, satisfactory outcomes were achieved both in functional and esthetic aspects.

• Journal of East-West Nursing Research
• /
• v.28 no.2
• /
• pp.142-150
• /
• 2022

Purpose: The purpose of this study is to identify the factors affecting the role of nurses with regard to the perception of good death, knowledge of advance directives, and stress and attitude toward withdrawing life-sustaining treatment. Methods: Data were collected from 102 nurses working at a general hospital. Data were analyzed by descriptive statistics, independent t-test, one-way ANOVA, Scheffé test, Pearson correlation coefficient, and multiple linear regression using the SPSS 28.0.1.0 program. Results: Educational level (β=.37, p=.001 for bachelor; β=.33, p=.005 for master or higher) and good death perception (β=.22, p=.024) were significant factors of the role of nurses associated with withdrawing life-sustaining treatment. Conclusion: Based on the result of this study, information about awareness of good death should be included in development of an educational program in order to strengthen the role of nurses in withdrawing life-sustaining treatment of patients.

• Journal of Distribution Science
• /
• v.20 no.10
• /
• pp.67-77
• /
• 2022

Purpose: This study aims to determine the online shop service performance of fresh food products distribution, consumer motivation, and their relationship during the COVID-19 pandemic. Research design, data, and methodology: A survey was conducted online using Google Forms on 100 consumers of TaniHub application users. Data in the form of scale were analyzed descriptively to explain the service performance and consumer motivation. The service performance consists of technical services and marketing services. Technical service indicators consist of payment, delivery, and products. Meanwhile, the marketing service indicator consists of promotions and prices. The consumer motivation is characterized by reference, actualization, and lifestyle. The relationship between the two was analyzed using Spearman's rank correlation. Results: The most consumers are millennial generation who were active in social media. They are employees with Bachelor's and Master's qualifications and included in the middle economic groups. TaniHub online shop had good technical and fair marketing performance. The motivation of online shop consumers of fresh food products through the TaniHub application was high. Conclusions: The findings discovered a significant relationship between online shop service performance and consumer motivation. It indicates the need for improvement in marketing services, especially promotions, to improve the performance of this e-agribusiness company.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.4
• /
• pp.157-166
• /
• 2022

The most commonly used wireless communication technologies in IoT technology include ZigBee, WiFi, Bluetooth, and Z-Wave. In particular, Z-Wave is currently one of the preferred wireless communication technologies, with a global market share of 60 % of these technologies. In this research, a temperature and humidity sensor module using a Z-wave protocol was designed and manufactured by referring to the data sheet. Subsequently, the Z-Wave protocol was analyzed during the operation of the sensor module, and the firmware of the controller module was mounted and implemented. In addition, a program for monitoring the temperature and humidity information from the sensor module was developed and validated. Finally, the performance of the sensor module was validated through master distance and low power tests on it and its reception data success rate.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.1396-1403
• /
• 2009

The Ministry of Construction and Transportation (MOCT) has been constructing a nationwide soil information DB since 2000, as basic data for the construction of 'underground geographical information,' a project under the 2nd National Geo-spatial Information System (NGIS) master plan. The inputted soil information includes not only underground conditions such as the layer depth, type, color, and groundwater level, but also engineering information that can be applied to construction work design, such as on the standard penetration test and the compression test. It is difficult to use this information in soil analysis and design, however, because only the test results are currently available. A web-based geo-spatial information system was developed in this study to facilitate the effective application of the soil information database (DB). First, the space information, layer information, and engineering test information were loaded from the soil information DB in real time, and the earth volume, bearing capacity, and settlement were calculated to develop a web client that will evaluate the ground softness and liquefaction. It seems that the soil information DB can be actively applied to the planning and design of construction works using this system.

• Journal of the Korean Society for Precision Engineering
• /
• v.10 no.2
• /
• pp.54-65
• /
• 1993

The paper describes and alternative method based on a new idea to measure the circular movement of machining centers. ISO has employed three testing methods for the acceptance tests of machine tools; the first is a rotating one-dimensional probe method, the second is a two-dimensional probe and a master circular ring, and the third is a kinematic ball bar. The last two methods were proposed and introduced by W. Knapp and J. B. Bryan, respectively. The newly developed method is superior to above two methods; the rotating angle can be detected and the rotating radius is variable. Circular movement errors of machining centers were investigated by the analysis of data measured by R- .THETA. method. Followint observations are obtained 1) The errors which depend on positions, i.e., periodical errors by the pitch of ball screws, errors by compensation of backlash and errors by perpendicularity of X and Y-axis, were analyzed. 2) The errors which depend on NC control system, i.e., errors by the unbalance of position-loop-gaians, errors by velocity-loop-gains and errors by feed speeds, were quantiatively analyzed. 3) The method of extracting error information, which uses moving technique of averaging angle and fourier's analysis data mesured by the R- .THETA. method, was proposed.

• Journal of Distribution Science
• /
• v.22 no.3
• /
• pp.71-81
• /
• 2024

Purpose: This study examines the impact of inclusive policies and green transformation on regional development of mining areas. Research design, data and methodology: We designed and utilized a structured questionnaire to collect data from a population of 300 individuals. The questionnaire was disseminated through Google Forms and consisted of five questions for each research variable. A total of 210 respondents completed the questionnaire, yielding a response rate of 70%. The sample was diverse in terms of gender and educational level Of the 210 respondents, 113 were female (53.8%) and 97 were male (46.2%). In terms of educational background, the sample was composed as follows: 13 individuals with a Doctorate degree (6.2%), 56 with a Master's degree (26.7%), 97 with a Bachelor's degree (46.2%), 22 with a Diploma (10.5%), and 22 with a High School education (10.5%). Results: The research outcomes highlight the significant influence of inclusive policies on driving the Distribution of green economic transformation. Emphasizing the pivotal role of inclusive distribution strategies, especially within the context of mining areas, the study sheds light on their crucial contribution to fostering regional development. Conclusion: These findings hold valuable implications for policymakers, industry stakeholders, and academics promoting environmentally conscious economic transformations.

• Journal of Korean Society for Quality Management
• /
• v.51 no.4
• /
• pp.573-588
• /
• 2023

Purpose: This study presents a research approach that utilizes deep reinforcement learning to construct optimal portfolios based on the business cycle for stocks and other assets. The objective is to develop effective investment strategies that adapt to the varying returns of assets in accordance with the business cycle. Methods: In this study, a diverse set of time series data, including stocks, is collected and utilized to train a deep reinforcement learning model. The proposed approach optimizes asset allocation based on the business cycle, particularly by gathering data for different states such as prosperity, recession, depression, and recovery and constructing portfolios optimized for each phase. Results: Experimental results confirm the effectiveness of the proposed deep reinforcement learning-based approach in constructing optimal portfolios tailored to the business cycle. The utility of optimizing portfolio investment strategies for each phase of the business cycle is demonstrated. Conclusion: This paper contributes to the construction of optimal portfolios based on the business cycle using a deep reinforcement learning approach, providing investors with effective investment strategies that simultaneously seek stability and profitability. As a result, investors can adopt stable and profitable investment strategies that adapt to business cycle volatility.

• Hip & pelvis
• /
• v.35 no.1
• /
• pp.15-23
• /
• 2023

Purpose: Hip microinstability is defined as hip pain with a snapping and/or blocking sensation accompanied by fine anatomical anomalies. Arthroscopic capsular plication has been proposed as a treatment modality for patients without major anatomic anomalies and after failure of properly administered conservative treatment. The purpose of this study was to determine the efficacy of this procedure and to evaluate potential predictors of poor outcome. Materials and Methods: A review of 26 capsular plications in 25 patients was conducted. The mean postoperative follow-up period for the remaining patients was 29 months. Analysis of data included demographic, radiological, and interventional data. Calculation of pre- and postoperative WOMAC (Western Ontario and McMaster Universities Osteoarthritis) index was performed. Pre- and postoperative sports activities and satisfaction were also documented. A P<0.05 was considered significant. Results: No major complications were identified in this series. The mean pre- and postoperative WOMAC scores were 62.6 and 24.2, respectively. The WOMAC index showed statistically significant postoperative improvement (P=0.0009). The mean satisfaction rate was 7.7/10. Four patients with persistent pain underwent a periacetabular osteotomy. A lateral center edge angle ≤21° was detected in all hips at presentation. We were not able to demonstrate any difference in postoperative evolution with regard to the presence of hip dysplasia (P>0.05), probably because the sample size was too small. Conclusion: Capsular plication can result in significant clinical and functional improvement in carefully selected cases of hip microinstability.