• International conference on construction engineering and project management
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• 2022.06a
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• pp.1250-1251
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• 2022

Measuring management is an important part of preventing the collapse of retaining walls in advance by evaluating their stability with a variety of measuring instruments. The current work of measuring management requires considerable human and material resources since measurement companies need to install measuring instruments at various places on the retaining wall and visit the construction site to collect measurement data and evaluate the stability of the retaining wall. It was investigated that the applicability of the current work of measuring management is poor at small and medium-sized urban construction sites(excavation depth<10m) where measuring management is not essential. Therefore, the purpose of this study is to develop a laser sensor-based hardware to support the wall displacement measurements and their control software applicable to small and medium-sized urban construction sites. The 2D lidar sensor, which is more economical than a 3D laser scanner, is applied as element technology. Additionally, the hardware is mounted on the corner strut of the retaining wall, and it collects point cloud data of the retaining wall by rotating the 2D lidar sensor 360° through a servo motor. Point cloud data collected from the hardware can be transmitted through Wi-Fi to a displacement analysis device (notebook). The hardware control software is designed to control the 2D lidar sensor and servo motor in the displacement analysis device by remote access. The process of analyzing the displacement of a retaining wall using the developed hardware and software is as follows: the construction site manager uses the displacement analysis device to 1)collect the initial point cloud data, and after a certain period 2)comparative point cloud data is collected, and 3)the distance between the initial point and comparison point cloud data is calculated in order. As a result of performing an indoor experiment, the analyses show that a displacement of approximately 15 mm can be identified. In the future, the integrated system of the hardware designed here, and the displacement analysis software to be developed can be applied to small and medium-sized urban construction sites through several field experiments. Therefore, effective management of the displacement of the retaining wall is possible in comparison with the current measuring management work in terms of ease of installation, dismantlement, displacement measurement, and economic feasibility.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.2
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• pp.101-120
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• 2023

Electrical resistivity survey have been widely conducted at diverse scales, from a few centimeters for laboratory tests to kilometers for field tests. It measures electrical resistance through relationship of electric potential difference and current between two electrodes penetrated on the surface of medium, and eventually quantifies electrical resistivity known as inherent properties of the medium. In field or full-scale test, it assumes the electrodes as equivalent half-sphere electrodes that have a same surface area with different electrodes for ease of calculation because the contact area between electrode and medium is small and sufficient distance between two electrodes. However, small-scale laboratory test is significantly affected by the electrode geometries (penetrated depth, height, radius of electrode and distance between electrodes), which change the equipotential surface and electric current flow. Indeed, the electrode geometries may eventually cause a difference of electrical resistivity value. This study reviews the theoretical electrical resistance derived with various electrode geometries (half-sphere, cylinder, cylindrical with half-spherical tip, cylindrical with conical tip) and verifies the developed numerical module by comparing results with the theoretical electrical resistance. The distributions of electrical resistance around electrodes and among electrodes are analyzed. In addition, it is discussed how the electrical characteristic of cylindrical electrode with conical tip widely used in field test has effect on the electric current flow.

• Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.105-116
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• 2023

Improved fish post-harvest technologies (IFPT) have been promoted as more efficient methods of fish processing, preservation, and value addition than the traditional methods prevalent in developing countries. The adoption rates, however, do not appear to be convincing. The purpose of this study was to determine the socio-demographic and psychological factors that influence intention of Kenyan farmed fish traders to use IFPT. The technology acceptance model (TAM) was used to properly explain the impact of TAM constructs such as perceived usefulness (PU), perceived ease of use (PEOU), and attitude (ATT), as well as socio-demographic factors such as gender, age, education level and fish trading experience on traders' intention to use the technologies. A cross-sectional survey was conducted to collect data using a semi-structured questionnaire from 146 traders in Busia, Siaya and Kakamega counties. At a significance level of p = 0.05, a linear regression model was used to examine the socio-demographic and psychological determinants of the traders' behavioral intention to use the improved technologies. The regression analysis revealed that PU (β = 0.443; p = 0.000), PEOU (β = 0.364; p = 0.000) and ATT (β = 0.615; p = 0.000) influence traders' intention to use IFPT, with ATT having the highest influence on intention. However, the traders' socio-demographic characteristics have no effect on their intention to use the technologies, as the coefficients for gender (β = 0.148; p = 0.096), age (β = 0.016; p = 0.882), level of education (β = -0.135; p = 0.141) and fish trading experience (β = 0.017; p = 0.869) are all insignificant. These findings show that the traders intend to use IFPT and will use them when it is in their best economic interests.

• Journal of the Korea Convergence Society
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• v.13 no.1
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• pp.375-386
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• 2022

Work involving standing or walking for a long time can cause swelling, pain, and fatigue in the lower extremities due to the effect of gravity on the circulation of the body. This study aimed to confirm the effects of aromatherapy essential oils, as a complementary and alternative therapy, on lower extremity edema, pain, and fatigue when applied as a foot bath or spray. The study was conducted after daytime work over two consecutive days on nurses who volunteered at the E University Hospital in D Metropolitan city between 15 August 2018 and 11 October 2018. This randomized controlled study. The foot bath group received a foot bath in 9 L of water containing 0.5 ml of essential oil blended with grapefruit and peppermint in a 1:1 ratio. The spray group received the same solution in 3% dilution in the form of a spray. Edema was assessed by measuring calf and ankle circumference, while pain and fatigue were evaluated using a numerical rating scale. Data were analyzed by ANOVA and repeated-measures ANOVA. The calf circumference in the foot bath and spray groups significantly reduced compared to that in the control group (F = 14.053, p <.001) after the interventions. Lower extremity pain (F = 42.497, p < .001) and fatigue (F = 20.641, p < .001) also significantly reduced in the foot bath and spray groups compared to those in the control group after the interventions. Foot bath is recommended to relieve swelling and pain in the lower extremities, and aroma spray is highly recommended considering the ease of application.

• Journal of Korean Library and Information Science Society
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• v.53 no.1
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• pp.231-263
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• 2022

The understanding and capability to utilize artificial intelligence (AI) incorporated technology has become a required basic skillset for the people living in today's information age, and various members of the university have also increasingly become aware of the need for AI education. Amidst such shifting societal demands, both domestic and international university libraries have recognized the users' need for educational content centered on AI, but a user-centered service that aims to provide personalized recommendations of digital AI educational content is yet to become available. It is critical while the demand for AI education amongst university students is progressively growing that university libraries acquire a clear understanding of user intention towards an AI educational content recommender system and the potential factors contributing to its success. This study intended to ascertain the factors affecting acceptance of such system, using the Extended Technology Acceptance Model with added variables - innovativeness, self-efficacy, social influence, system quality and task-technology fit - in addition to perceived usefulness, perceived ease of use, and intention to use. Quantitative research was conducted via online research surveys for university students, and quantitative research was conducted through written interviews of university librarians. Results show that all groups, regardless of gender, year, or major, have the intention to use the AI-related Educational Content Recommendation System, with the task suitability factor being the most dominant variant to affect use intention. University librarians have also expressed agreement about the necessity of the recommendation system, and presented budget and content quality issues as realistic restrictions of the aforementioned system.

• Journal of Aerospace System Engineering
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• v.16 no.1
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• pp.86-96
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• 2022

The development trend of jet fighter's avionics system architecture is the digitization of subsystem component functions, increased RF sensor sharing, fiber optic channel networks, and modularized integrated structures. The avionics system architecture of the fifth generation jet fighters (F-22, F-35) has evolved into an integrated modular avionics system based on computing function integration and RF integrated sensor systems. The integrated modular avionics system of jet fighters should provide improved combat power, fault tolerance, and ease of jet fighter control. To this aim, this paper presents the direction and requirements of the next-generation jet fighter's avionics system architecture through analysis of the fifth generation jet fighter's avionics system architecture. The core challenge of the integrated modularized avionic system architecture requirements for next-generation fighters is to build a platform that integrates major components and sensors into aircraft. In other words, the architecture of the next-generation fighters is standardization of systems, sensor integration of each subsystem through open interfaces, integration of functional elements, network integration, and integration of pilots and fighters to improve their ability to respond and control.

• Korea Trade Review
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• v.42 no.1
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• pp.283-301
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• 2017

As a consequence of the changed role and functions in port operations, the role of port hinterland has transformed to multi-functional logistic centre linking more efficiently elements of the supply chain. This paper analysed distribution centre selection factors in Busan new port hinterland, aiming to diagnose and evaluate the operational situations of port hinterland as multi-functional logistics centre. Based on a data collected from all 122 samples located in Busan new port hinterland, determinants for location competitiveness identified were: political support, market potentiality, infrastructure utilization, market niche, and connectivity. Comparing the difference between an importance and performance, it is revealed that the target port hinterland requires urgent improvement in political supports such as incentive programmes offered by host country, free trade system and related law, financial assistance in constructing distribution centers, and simplicity, ease and efficiency of administrative procedures. The results provide useful insights for establishing future improvement strategies and a strategic agenda to successfully respond to the demands of the companies located in port hinterlands and/or new customers those who want to move in.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.6
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• pp.493-503
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• 2018

The present study is a conceptual replication of O'Grady, Lee, and Choo's (2003) earlier study designed to investigate two hypotheses (linear distance hypothesis vs. structural distance hypothesis) in relation to L2 Korean learners' processing of Korean subject and object relative clauses (RCs) in a scholarly attempt to explicate Keenan and Comrie's (1977) Noun Phrase Accessibility Hierarchy (NPAH). In addition, the current study is intended to explore any potential role of working memory capacity (WMC) in the processing of Korean subject and/or object RCs. Chinese-speaking learners of Korean taking a language course offered at a local university in Korea participated in this experimental study. Among those recruited, only 23 learners completed the experimental tasks appropriately according to the specific instructions provided on each task, and thus, subsequent statistical analyses were conducted on their data. Fifteen Korean NSs were also recruited for the control group. Two experimental tasks were administerd to the participants: one picture selection task containing the same test items used in O'Grady et al.'s study to measure their processing of subject-object RCs and an operation span (OSPAN) task to measure their WMC. Somewhat differently from O'Grady et al.'s findings, the participating Chinese learners of Korean performed significantly better on object RCs than on subject RCs, seemingly lending support to the linear distance hypothesis. Further analyses, however, suggested that the results in favor of, or relative ease of processing, object relative clauses were due, most likely, to the learners' excessive use of the canonical sentence strategy, which also led to nonsignificant correlations between WMC and learner performance on the picture selection task.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.2
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• pp.169-178
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• 2016

The number of people with disabilities is increasing recently in Korea, in particular the proportion of children with disabilities is approximately above 5%. While there are many studies focusing on satisfaction of payment policy due to increased concern about children with disabilities, the studies on comparison and the effect factor of user satisfaction depending on the cash and voucher are not sufficient. Based on the need to recognize and research this issue, the ultimate goal of this study is to lead to implications for the payment policy by investigating user satisfaction depending on the type of payment of policy on children with disabilities. The result that analyzes the effect of general characteristics on user satisfaction shows that in case of in-cash, children and the degree of disability affect user satisfaction. In the case of voucher, the gender of parents, the degree of disability and the average income affect it. The implication of this study suggests practical implication and policy implication. Implications of the study is that provide a customized service considering general characteristics. Second, It needs to extend the range of amount of payment of in-cash. Third, extend and pay the amount of in-cash, and the service of voucher. Fourth, provide low-income group(including public aid recipients and near poverty group) with voucher to ease financial burden.

• Journal of agricultural medicine and community health
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• v.48 no.2
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• pp.81-90
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• 2023

Objectives: This study analyzed the decline in quality of life according to age in the chronic disease patient group, quantified it as a quantitative index, and compared it by sex and chronic disease. Methods: In the 2017-2019 Korea National Health and Nutrition Examination Survey database, 11,473 adults aged 19 years or older, excluding cancer patients, were analyzed for age-specific changes in the EQ-5D Index by chronic disease. The decline in quality of life according to age in patients with chronic diseases was analyzed by linear regression analysis while controlling for general characteristics. Then, linear regression analysis was performed according to sex. Results: In the case of the control group, the quality of life decreased by 0.0004 for every 1-year increase in age(P<0.001). By chronic disease, asthma(β=0.0019, P<0.001), arthritis(β=0.0017, P=0.002), thyroid dis- ease(β=0.0016, P=0.015), dyslipidemia(β=0.0011, P=0.020), and hypertension(β=0.0009, P=0.027) mostly showed a greater decrease in quality of life than the control group. In addition, when divided into two groups by sex, hypertension(β=0.0012, P=0.029), thyroid disease(β=0.0041, P=0.038), and arthritis(β=0.0022, P<0.001) showed a significant decrease in quality of life only in male. Diabetes(β=0.0056, P=0.038), dyslipi- demia(β=0.0022, P=0.001) significantly decreased quality of life only in female. Conclusions: Chronic disease had a negative impact on patients perception of quality of life, and the more severe the pain and activity limitation due to the chronic disease, the more severe it was. It also showed different patterns according to sex. Therefore, it is necessary to allocate more medical resources and provide policy support to prevent chronic diseases, which are serious social problems.