• Applied Chemistry for Engineering
• /
• v.34 no.1
• /
• pp.23-29
• /
• 2023

Microfluidic reactors have been made to achieve significant development for the generation of new functional materials to apply in a variety of fields. Over the last decade, microfluidic reactors have attracted attention as a user-friendly approach that is enabled to control physicochemical parameters such as size, shape, composition, and surface property. Here, we develop a centrifugal microfluidic reactor that can control the flow of fluid based on centrifugal force and generate multifunctional particles of various sizes and compositions. A centrifugal microfluidic reactor is fabricated by combining microneedles, micro- centrifuge tubes, and conical tubes, which are easily obtained in the laboratory. Depending on the experimental control param- eters, including centrifuge rotation speed, alginate concentration, calcium ion concentration, and distance from the needle to the calcium aqueous solution, this strategy not only enables the generation of size-controlled microparticles in a simple and reproducible manner but also achieves scalable production without the use of complicated skills or advanced equipment. Therefore, we believe that this simple strategy could serve as an on-demand platform for a wide range of industrial and academic applications, particularly for the development of advanced smart materials with new functionalities in biomedical engineering.

• Journal of the Korean Geotechnical Society
• /
• v.38 no.5
• /
• pp.5-17
• /
• 2022

A pile is a type of medium for constructing superstructures in weak geotechnical conditions. A pretensioned spun high-strength concrete (PHC) pile is composed of high-strength concrete with a specified strength greater than 80 MPa. Therefore, it has advantages in resistance to axial and bending moments and quality control and management since it is manufactured in a factory. However, the skin friction of a pile, which accounts for a large portion of the pile bearing capacity, is only approximated using empirical equations or standard penetration test (SPT) N-values. Particularly, there are some poor research results on the pile-soil interface under the seismic loads in Korea. Additionally, some studies do not consider geoenvironmental elements, such as groundwater pH values. This study performs sets of cyclic simple shear tests using submerged concrete specimens for 1 month to consider pH values of groundwater and clay specimens composed of kaolinite to generate a pile-soil interface. 0.2 and 0.4 MPa of normal stress conditions are considered in the case of pH values. The disturbed state concept is employed to express the dynamic behavior of the interface, and the disturbed function parameters are newly suggested. Consequently, the largest disturbance increase under basic conditions is observed, and an early approach to the failure under low normal stress conditions is presented. The disturbance function parameters are also suggested to express this disposition quantitatively.

• International Journal of Computer Science & Network Security
• /
• v.22 no.10
• /
• pp.183-190
• /
• 2022

The article analyzes the features of the formation of a person's value attitude to the worldview by means of information technologies. The present considers it necessary to form a person's value attitude to the perception of the world by means of information technologies. The explosive development of information and telecommunications technologies has become a determining factor in the development of modern society, which is called the information or Global Information Society. It is not yet fully formed, and we are all participants in the development of the Global Information Society. The article considers the basics of a harmonious worldview of a person, which is the basis for the formation of outlook ideas, views, knowledge, beliefs about the surrounding world, which determine the place and role and motivate actions in relation to the surrounding reality through the prism of value orientations. Worldview is considered as an integrity of relatively stable schemes, behaviors, feelings, thinking, vision of the surrounding world, inherent in an individual child, ethno-cultural and socio-cultural groups. The concept of "worldview" as a component of the multi-level structure of the individual's outlook is defined. The features that characterize a person's perception of the world are revealed. The main educational value of information technologies in the formation of a person's value attitude to the perception of the world is highlighted, which consists in the fact that they allow you to create an immeasurable brighter multi-sensory interactive learning environment with almost unlimited potential opportunities that fall at the disposal of both the teacher and the student. The trend of forming a person's value attitude to the perception of the world is clearly developing in the direction of mixed learning as a process that creates a comfortable information educational environment, communication systems that provide all the necessary educational information. The approach to student development by means of the educational environment and the formation, while in the person of a value attitude to the perception of the world by means of Information Technologies, has many pedagogical advantages, which is considered in the article.

• Journal of Wetlands Research
• /
• v.24 no.3
• /
• pp.155-160
• /
• 2022

The debate of South-North transboundary rivers must be expanded from the existing cooperation in water resources towards cooperation within ecosystem conservation. Regarding the Han and Imjin rivers confluence water system, the nature of the estuarine ecosystem must be conserved considering the aspect of climate change. Furthermore, the agenda of maintaining continuous inter-Korean communication and cooperation should focus on ecosystem conservation, including conserving migratory species that inhabit both Koreas. Notably, within the Han and Imjin rivers confluence, transboundary rivers are abundant legally protected species such as Grus vipio, Anser fabalis, Anser cygnoides, Platalea minor, Lutra lutra, Prionailurus bengalensis which suggests a strong need for a debate regarding habitat conservation. This study analyzed the ecosystem conditions and environmental aspects within the confluence of Han and Imjin rivers. In addition, this study provided step wise approach of ecosystem conservation that consider conditions for potential direct inter-Korean cooperation. The inter-Korean cooperation mentioned in this study will be developed into legitimate cooperation once the results from monitoring the ecosystem of transboundary rivers, awareness raising are exchanged.

• Journal of Service Research and Studies
• /
• v.10 no.4
• /
• pp.21-41
• /
• 2020

As the 4th Industrial Revolution unfolds rapidly, it is important to re-light the intrinsic mission given to universities from a system theory perspective as a condition for the university to survive. In this study, the university was prescribed as a fifth service industry that creates high value-added through higher education services, and attempted to provide a new and novel perspective to various university officials for the scientific rationalization of university management by re-describing it based on the Multidisciplinary perspective based on business administration, but in particular on the theory of service operation management. To this end, the primary purpose of this study is to classify the nature of educational organizations, research organizations, service organizations, and support organizations to properly perform the university's essential mission of education, research, and service, and to explore concepts and techniques for performing management activities that are appropriate to them. In addition, after identifying the university from an academic and practical point of view as a fifth service industry that creates high value-added through higher education services, but more specifically, to provide a new perspective and means for the scientific rationalization of university management by re-identifying university administration based on the business administration theory, in particular the theory of service operation management, and further reflecting a recent trend to view the university president from the CEO's point of view, the specific purpose of this study is to look at this academic system. Through this, we sought the ideal form of a systematic and scientific university management organization that can respond to new environmental changes.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.5
• /
• pp.512-519
• /
• 2023

Noise pollution poses significant challenges to human well-being and marine ecosystems. It is primarily caused by the flow around ships and marine installations, emphasizing the need for accurate noise evaluation of flow noise to ensure environmental safety. Existing flow noise analysis methods for underwater environments typically use a hybrid method combining computational fluid dynamics and Ffowcs Williams-Hawkings acoustic analogy. However, this approach has limitations, neglecting near-field effects such as reflection, scattering, and diffraction of sound waves. In this study, an alternative using direct method flow noise analysis via the lattice Boltzmann method (LBM) is incorporated. The LBM provides a more accurate representation of the underwater structural boundaries and acoustic wave effects. Despite challenges in underwater environments due to numerical instabilities, a novel DM-TS LBM collision operator has been developed for stable implementations for hydroacoustic applications. This expands the LBM's applicability to underwater structures. Validation through flow noise analysis in pipe orifice demonstrates the feasibility of near-field analysis, with experimental comparisons confirming the method's reliability in identifying main pressure peaks from flow noise. This supports the viability of near-field flow noise analysis using the LBM.

• Journal of International Area Studies (JIAS)
• /
• v.15 no.1
• /
• pp.83-108
• /
• 2011

South America has vast energy resources with the renewable and non-renewable sources. However, many countries in the region are unable to guarantee adequate energy security both of energy supply and demand. Currently the possibility of energy security is high through regional energy integration based on the potential economic benefits. The difference of regulation system with the individual countries in the region impose strong barriers to integration process. Security of energy supply and its demand as well is fundamental issues in this region and regional energy cooperation is essential for getting rid of the insecurity of energy supplies. Despite of this problem, currently Latin American countries made a great effort to make multilateral energy security regime through projecting great energy infrastructure network(e.g. IIRSA) or mechanism especially in South America, which can give countries access to the region's reserve supplies by providing regulations and pricing mechanism with a shared energy market in this region. Brazil's active leading in the formulation of such movement toward energy security integration and participation of energy infrastructure network is good initiative to enforce this great energy security change. Politically and economically, Brazil's geographical position and the level of market size and oil and natural gas resources, in addition the leadership in renewable energy sources make it a sound candidate to take over the coordination of the secure integration of region's energy market. However, on the conditions of existing many obstacles such as, control of the output of the region's power plant, energy flows, the environmental matter within local community must be overcome to make more advance process and steps. Finally, to secure more institutional approach, this region must settle regional disputes resolution regime urgently.

• The Korean Journal of Coaching Psychology
• /
• v.5 no.2
• /
• pp.25-51
• /
• 2021

The purpose of this study is to deeply explore the communication process with team members perceived by team leader. To this end, in-depth interviews were conducted with 10 team leaders, and analyzed according to the grounded theory research method procedure suggested by Strauss and Corbin. As a results, a total of 51 concepts, 17 subcategories, and 8 categories were derived. As a causal condition, the concept of 'contemplating and reinterpreting communication necessary for the organization' was derived, and the central phenomenon was 'intentional effort made in parallel with work and private conversations'. The contextual condition was 'recognizing the need to cope with environmental changes', and the mediating condition was 'self-reflection and self-coaching time' was derived. The action/interaction strategy was conceptualized as a communication process with task-oriented coping, conflict resolution coping, and relationship promotion coping, and was confirmed as 'recognizing virtuous cycle communication within the organization' as a result of interaction with the central phenomenon. As a result of analysis of the team leader's communication process, the effort stage, approach stage, coping stage, and cycle stage were shown. As a result of the type analysis, task-oriented coping was a facilitator, conflict resolution coping was a supporter, and relationship promotion coping was a considerate. This study is an empirical study on how the corporate team leader perceives and expresses communication in the relationship with the team members.

• Journal of Internet of Things and Convergence
• /
• v.9 no.2
• /
• pp.61-69
• /
• 2023

In recent years, due to heightened environmental awareness, Electric Power Steering (EPS) has been increasingly adopted as the steering control unit in manufactured vehicles. This has had numerous benefits, such as improved steering power, elimination of hydraulic hose leaks and reduced fuel consumption. However, for EPS systems to respond to actions, sensors must be employed; this means that the consistency of the sensor's linear variation is integral to the stability of the steering response. To ensure quality control, a reliable method for detecting defects and assessing linearity is required to assess the sensitivity of the EPS sensor to changes in the internal design characters. This paper proposes a data-driven defect and linearity assessment monitoring system, which can be used to analyze EPS component defects and linearity based on vehicle speed interval division. The approach is validated experimentally using data collected from an EPS test jig and is further enhanced by the inclusion of a Graphical User Interface (GUI). Based on the design, the developed system effectively performs defect detection with an accuracy of 0.99 percent and obtains a linearity assessment score at varying vehicle speeds.

• Journal of the Korean Geotechnical Society
• /
• v.23 no.12
• /
• pp.61-73
• /
• 2007

As a part of Load and Resistance Factor Design(LRFD) code development in Korea, in this paper an intensive reliability analysis was performed to evaluate reliability levels of the two static bearing capacity methods for driven steel pipe piles adopted in Korean Standards for Structure Foundations by the representative reliability methods of First Order Reliability Method(FORM) and Monte Carlo Simulation(MCS). The resistance bias factors for the two static design methods were evaluated by comparing the representative measured bearing capacities with the design values. In determination of the representative bearing capacities of driven steel pipe piles, the 58 data sets of static load tests and soil property tests were collected and analyzed. The static bearing capacity formula and the Meyerhof method using N values were applied to the calculation of the expected design bearing capacity of the piles. The two representative reliability methods(FORM, MCS) based computer programs were developed to facilitate the reliability analysis in this study. Mean Value First Order Second Moment(MVFOSM) approach that provides a simple closed-form solution and two advanced methods of FORM and MCS were used to conduct the intensive reliability analysis using the resistance bias factor statistics obtained, and the results were then compared. In addition, a parametric study was conducted to identify the sensibility and the influence of the random variables on the reliability analysis under consideration.