• Membrane and Water Treatment
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• v.8 no.2
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• pp.125-136
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• 2017

Reverse osmosis technology is being used on large scale for treatment of ground water, brackish water, wastewater and sea water. The most challenging issue in RO process is carbonate scaling which is directly linked with the efficiency and economy. Considering the natural phenomena of carbonate scaling different adaptations have been made to control scaling on the surface of RO membrane including acid dosage and antiscalant addition. As carbonate scaling is directly related with pH level of feed water, present study describes an experimental approach to reduce scaling on RO membrane by lowering the feed water pH by purging $CO_2$. In this comparative study four different conditions including control process (without any scale inhibitor), with dosage of antiscalant, with purging of $CO_2$ and with co addition of antiscalant and $CO_2$ in a feed stream line; it was established that $CO_2$ is a better appliance to reduce carbonate scaling on the membrane surface by reduce pH of feed stream. It was also observed that $CO_2$ and antiscalant mutually function better for scale control.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.8
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• pp.11-17
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• 2021

This paper describes the time rate of change of dynamic response of a cantilever beam inserted with a damping element, such as bonding, which is excited under a general force at various locations. A sensitivity analysis was performed in a finite element model to show that two types of second-order algebraic governing equations were used to predict the rate of change of dynamic displacement: one is related to the modal coordinate linked to a physical coordinate, and the other to the design parameter of the time rate of change of displacement. The sensitivity differential equation formulation includes more complicated terms compared with that of the undamped cantilever beam. The sensitivities of the dynamic response were observed by changing the location of the excitation force, displacement extraction, and cross-sectional area of the beam. The analytical results obtained by this suggested theory showed a relatively good agreement when compared with those obtained using the commercial finite element program. The suggested analysis procedure enables the prediction of the response sensitivity for any finite element model of the dynamic system.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.1
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• pp.5-17
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• 2021

This study is a literature review on the recovering phosphorus from Incinerated Sewage Sludge Ash(ISSA), which has relatively high content of phosphorus. Experimental conditions and influencing factors related to the recovery of P and removal of heavy metals by wet and thermochemical methods were discussed. For the practical application of the recovery of P from ISSA, an integrated process linked to incineration facilities is required in terms of economy from the perspective of the entire system including disposal of wastewater and residues generated during the recovery process, and minimizing added chemicals and energy consumption.

• Journal of Agricultural Extension & Community Development
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• v.29 no.1
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• pp.1-18
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• 2022

The government is in the process of pursuing various resident-driven rural development projects for rural development. Accordingly, the government is promoting various software projects to enhance social capital in order to effectively involve residents in rural development projects. However, residents' participation in rural development projects is still passive, while passive residents' involvement creates various problems such as conflicts among residents in the process of project implementation and poor operation after project implementation. This study is intended to be a basis for inducing voluntary community participation in rural development projects by disclosing the intention of residents to participate in the community's internal solidarity with social capital and connection with external communities. According to the analysis of 195 rural residents, three groups were divided according to the level of social capital awareness. While individualist groups with low integration and social capital were 25.1%, they were more integrated, but the average family-oriented group was 42.5%, and social-development groups with high integration and linked social capital were 32.3%. This study is meaningful in that it revealed that the social capital of the resident community is an important factor in both the internal solidarity (integrity) and the external community connection (connectivity) in the rural area development project.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.220-224
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• 2022

The teacher is considered the cornerstone of the educational process; the quality of education is linked mainly to teachers who perform such a necessary process. The shift in pedagogical thinking has led to progress in looking at the teacher's roles; he is no longer transferring knowledge to learners, but instead, he has become a mentor, a mediator, a planner, an intellect, and a leader. If we analyze these missions from the perspective of mental habits, we will see that they require the teacher to develop the skills of perseverance, listening comprehension, thinking flexibly, controlling emotions, self-confidence, communication skills, and other essential skills. The current research verifies the effectiveness of an instructional program based on web quests in developing habits of the mind of English language students. The study employed a quasi-experimental design. The sample consisted of 46 male students representing two classes. They were assigned randomly into an experimental group (n=24) and a control group (n=22). They were undergraduate students majoring in the English language. The findings showed a statistically significant difference in the mean scores of the experimental and control groups favoring the experimental group. The study concludes with some recommendations to differentiate teaching techniques in EFL classrooms.

• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.1
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• pp.82-95
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• 2022

Since military weapon accidents or breakdowns are directly linked to enormous damage, it is important to analyze the causes of weapons system accidents. Recently, in the defense sector, there have been cases in which budget has been saved through analysis of the causes of frequent breakdowns and improvement activities that have occurred in the process of operating weapon systems since 2015. But due to the nature of the defense sector, it is not easy to collect data and studies on weapons system accidents have been insufficient so far. Therefore, this study aims to investigate the causes and types of military weapon accidents by collecting military weapon accident data for military weapon systems and analyzing trends by weapon system classification through the analysis process. It analyzes statistically and visually through social network analysis, NodeXL. It is expected that this study will help improve the stability of the weapon system by reducing the number of military weapon accidents and failures.

• Journal of Korean Society of Rural Planning
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• v.28 no.3
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• pp.35-47
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• 2022

The study is to analyze the role of highschool youth group in a rural regeneration project. The process of youth group becoming subjective in resident participation plan was classified into isolation reduction, self-awareness, perspective-taking, subjectivity practice, and opinion expression. Isolation reduction is a stage in which youth group is gradually drawn into the community from a limited society of home and school, self-awareness is a stage in which they discover their thoughts, and view perspective-taking is a stage in which they objectify themselves and surroundings through communication with other members of the region, social experiment was analyzed as a practice of subjectivity that experiences leadership guiding the local community independently, and expressing opinions is a stage of representing the region and giving responsibility for the specific issue of the implementation plan. The study is also an analysis of how residents committee, local governments, and local research institutes perform both regeneration and community revitalization in rural areas. Therefore, the analysis of the cooperative organization of these institutions was conducted simultaneously. The leadership program was effectively linked to the project of rural regeneration. Since high school students themselves are family members of the local people, the process of accepting the project is unaffected, and the feasibility of the project is also increased, such as forming a positive atmosphere for the project and easing resistance to minority opinions.

• Journal of Korean Medical classics
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• v.35 no.3
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• pp.71-90
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• 2022

Objectives : This paper summarizes contents on fish in the Injeji and Jeoneo-Ji parts in the Imwon-Gyeongje-Ji and compares them with those in the Dong-uibogam from a Korean Medical perspective. Methods : Most of the knowledge of fish in the Imwon-Gyeongje-Ji is based on preceding material medica studies such as the Dongui-bogam in Joseon, the Bencao-gangmu in China, and the Hwahan Samjaedohoe in Japan. The influential relationships and the process of change among these knowledge information were examined within the context of each literature's development or through identifiable changes in knowledge on each particular kind of fish. Results & Conclusions : In the Imwon-Gyeongje-Ji, the consisting 16 parts are organically connected, sometimes functioning as cross-references. In particular, the medical contents on the efficacy of fish for treating disease is closely linked to contents on fish ecology and environment as written in the Jeoneo-Ji, which deals with the field of living things. On the more detailed knowledge on about 30 kinds of fish, one could grasp the formation process and changes of East Asian traditional knowledge on fishkind among historical study of influential Chinese texts, new stimulation and methodology through Japanese literature on natural history, and dynamic processes of inheriting and selectively accepting traditional knowledge of Joseon.

• Molecules and Cells
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• v.38 no.9
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• pp.821-828
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• 2015

Monocytes are the major inflammatory cells that infiltrate most solid tumors in humans. The interaction of tumor cells with infiltrating monocytes and their adhesion to these monocytes play a significant role in altering the tumor to become more aggressive. Recently, exposure to lipopolysaccharide (LPS) was suggested to promote cancer cell adhesion to monocytes; however, little is known about the details of the signaling mechanism involved in this process. In this study, we found that LPS up-regulates ICAM-1 expression in MDA-MB-231 breast cancer cells, which facilitates their adhesion to THP-1 monocytes. In addition, we analyzed the signaling mechanism underlying the up-regulation of ICAM-1 and found that the siRNA-mediated depletion of BLT2 markedly suppressed the LPS-induced expression of ICAM-1 in MDA-MB-231 cells and the subsequent adhesion of these cells to THP-1 monocytes. Moreover, we demonstrated that myeloid differentiation primary response gene 88 (MyD88) lies downstream of LPS/TLR4 and upstream of BLT2 and that this 'MyD88-BLT2' cascade mediates ERK activation and subsequent ICAM-1 expression, which is critical for the adhesion of MDA-MB-231 cells to THP-1 monocytes. Taken together, our results demonstrate for the first time that LPS up-regulates ICAM-1 expression in breast cancer cells via a MyD88-BLT2-ERK-linked signaling cascade, leading to the increased adhesion of breast cancer cells to monocytes.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.511-514
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• 2002

Nowadays, domestic construction companies make an effort to share knowledge and experience accumulated while conducting a project. One way of improving knowledge sharing is to develop specifications which are linked to the expert's knowledge and experience based on the specification classification. Therefore, the purpose of this paper is to review the current domestic specification system and develop the specification linked to the construction lessons learned database. It is expected that the proposed specification system will support the decision making process by effectively providing the knowledge and solution.