• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.707-714
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• 2004

How to improve the cell culture method on scaffolds is important in the tissue engineering fileld. In this study, we optimized seeding and culture methods to vascular smooth muscle cells (VSMCs) on biodegradable polymer scaffold. The primary culture of VSMCs obtained from canine external jugular vein was accomplished by applying the explant-derived method. The primary cultured VSMCs were seeded into scaffolds and then cultured by using various different methods; static or dynamic seeding, static or dynamic culture. The difference in proliferative response of VSMCs was analyzed with an alamar blue assay. Cell-polymer construct was examined by histochemical method and scanning electron microscopy. Mesh type scaffold ($10 \times 10 \times0.4 mm$) was made of polyglycolic acid (PGA) suture thread. The PGA mesh type scaffold was 45% in porosity, and 0.03 g in weight. The primary cultured VSMCs were confirmed with immunohistochemical staining using monoclonal anti-$\alpha$-smooth muscle actin. The density and distribution of proliferated VSMCs within the scaffold and cellular adherence on the surface of the scaffold showed better results in the static seeding condition than in the dynamic condition. Under the same condition of seeding method as the static condition, the dynamic culture condition showed enhanced proliferation rates of the VSMCs when compared to the static culture condition. In conclusion, to improve the VSMCs proliferation in vitro, static seeding is better than the dynamic condition. In the culture condition, however, culture under the dynamic status is better than the static condition. This was a pilot study to manufacture artificial vascular vessel by tissue engineering.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.47-57
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• 2019

This study analyze whether the organizational learning culture affects the firm's dynamic capacity and whether the dynamic capacity mediates the relationship between organizational learning culture and management performance. Respectively. First, "The more organizational structure is organic, the higher the integrated relocation capacity and learning capacity. Organizations with organic organizational structures were found to have the ability to successfully adapt to external changes because there is a practice that is not tied to formal processing or procedures. Second, it can be seen that there is a positive (+) influence on the relocation capacity among the dynamic competence of the learning culture of the corporate organization. Third, both sub-factors of dynamic competence have positive (+) influence on business performance. Also, there was no mediating effect of dynamic competence related to learning culture.

• Advances in Computational Design
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• v.4 no.3
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• pp.307-326
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• 2019

A low computational cost semi-analytical method is developed, based on eigenfunction expansion, to study the vibration of rectangular plates subjected to a series of moving sprung masses, representing a bridge deck under multiple vehicle or train moving loads. The dynamic effects of the suspension system are taken into account by using flexible connections between the moving masses and the base structure. The accuracy of the proposed method in predicting the dynamic response of a rectangular plate subjected to a series of moving sprung masses is demonstrated compared to the conventional rigid moving mass models. It is shown that the proposed method can considerably improve the computational efficiency of the conventional methods by eliminating a large number of time-varying components in the coupled Ordinary Differential Equations (ODEs) matrices. The dynamic behaviour of the system is then investigated by performing a comprehensive parametric study on the Dynamic Amplification Factor (DAF) of the moving loads using different design parameters. The results indicate that ignoring the flexibility of the suspension system in both moving force and moving mass models may lead to substantially underestimated DAF predictions and therefore unsafe design solutions. This highlights the significance of taking into account the stiffness of the suspension system for accurate estimation of the plate maximum dynamic response in practical applications.

• Journal of the Ergonomics Society of Korea
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• v.33 no.4
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• pp.267-279
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• 2014

Objective: The objective of this study was to define the Dynamic Sitting (DS) through trend analysis and research on the Dynamic Chair (DC) and applied technologies. Background: The effects of changing posture on the human body have been studied to find out healthy sitting postures. It is believed that changing posture is effective in reducing disc pressure on spinal cord and preventing back pain and musculoskeletal disease. But, the definition of DS and trends of DC have not been researched yet. Therefore, trend analysis of DC and its applied technologies are required to define dynamic sitting posture. Method: We researched the type of occupant postures from previous studies. And then, sitting behaviors were classified into three types; (1) sitting and standing, (2) working and studying, (3) taking a rest. Results: Variety shapes of DC and applied technologies were found out. From the result, the trend of DC and applied technology were summarized from three perspectives. ; (1) changing the chair functions according to user's intention, (2) conversion of dynamic chair technologies to office chair mechanism, (3) enables the user to change their sitting posture without operating control device. Conclusion: From this study, we defined dynamic sitting posture and analyzed the trend of DC and its applied technologies. This result might be used to develop an office chair for healthy sitting. But further investigation is required to figure out the technologies and functions for development of healthy chair. Application: The results of the publishing trend analysis might help to determine design concept of office chair.

• Journal of Ocean Engineering and Technology
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• v.27 no.6
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• pp.7-15
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• 2013

Eco-friendly and sustainable seaweed biomass energy have been under the spotlight as the future of renewable energy. However, seaweed culture is primarily conducted inshore, with the research on offshore culture still in an early stage. For massive biomass production, a systematic engineering approach is required to devise offshore seaweed culture facilities rather than the conventional empirical ones. To establish the fundamental behavior of seaweed culture facilities, the dynamic characteristics of a seaweed culture facility were analyzed in the study. For this purpose, numerical analyses of the seaweed culture facility (a frame type) were carried out by using the hydrodynamic simulation program ANSYS-AQWA. For the analysis, environmental loads were considered using the wave spectra and co-linear current; mooring variables were selected as parameters; and time domain analyses were carried out to acquire the time series responses and eventually the dynamic characteristics. Finally, the mooring performance was evaluated. It was found that the motion could be controlled by adjusting the buoyancy and mooring slope.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.3
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• pp.146-151
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• 2016

Objective: This study was conducted to compare the effects of static culture, dynamic culture, and the combination of dynamic culture with specialized surfaces involving co-culture on human embryonic development. Embryos cultured using conventional static culture (SC) techniques served as a control group. We compared dynamic culture using micro-vibration culture (MVC) and micro-vibration with co-culture (MCoC), in which autologous cumulus cells were used as a specialized surface. Methods: We conducted a chart review of patients who were treated between January 2011 and November 2014 in order to compare embryonic development rates and pregnancy rates among the groups. Zygotes were cultured in micro-droplets, and embryos were subsequently selected for transfer. Some surplus embryos were cryopreserved, and the others were cultured for blastocyst development. A micro-vibrator was set at the frequency of 42 Hz for duration of 5 seconds per 60 minutes to facilitate embryo development. Results: No significant differences among the groups were present in patient's characteristics. However, the clinical pregnancy rates were significantly higher in the MVC group and the MCoC group than in the SC group. No significant differences were found in the blastocyst development rate between the SC group and the MVC group, but the blastocyst development rate in the MCoC group was significantly higher than in the SC and MVC groups. Conclusion: The clinical pregnancy rate was significantly increased by the application of micro-vibration to the embryonic cultures of poor responders. The blastocyst development rate was significantly increased by the application of MCoC to surplus embryos.

• Composites Research
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• v.32 no.5
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• pp.211-215
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• 2019

The cell culture process under in vitro condition is much different from the actual human body environment. Therefore, in order to precisely simulate the human body environment, a dynamic cell culture device capable of delivering mechanical stimulation to cells is essential. However, conventional dynamic cell culture devices require relatively complicated devices such as tubes, pumps, and motors, and the mechanical stimuli delivered is also simple. In this study, an electro-active polymer actuator as a driving component is introduced to design simply driven dynamic cell culture device without complicated components. The device is capable of delivering relatively complex mechanical stimuli to the cells.

• International Journal of Advanced Culture Technology
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• v.5 no.2
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• pp.63-73
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• 2017

In this paper, we propose algorithm for determining the static and dynamic posture using the acceleration sensor of smartphone. The measured acceleration values are then analyzed according to a preprocessing to the respective axis (X, Y, Z) and posture (standing, sitting, lying) presents static posture determination criterion. The proposed static posture determination condition is used for static posture determination and dynamic posture determination. The dynamic posture is determined by using regression linear equations. In addition, transition state can be grasped by SVM change in dynamic posture determination. Experimental results are presented using data and app. Experiments were performed using data collected from 10 adults.

• Journal of the Korean Society for information Management
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• v.27 no.2
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• pp.217-224
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• 2010

This paper starts with the question, what are culture and cultural resources? The meanings of cultural resources are mentioned historically and archaeologically. The culture dynamic is introduced and the cultural resources are interpreted as processes and practices along with which culture is produced and reproduced through the action of individual. Digital archiving concluds that the cultural resources are only meaningful when they are archived with their contexts and processes. Finally paper induces that cultural archives could be valuable, when they are preserved (synthetic), recognized (contextual) and enjoyed (exhibited, experienced or practically used).

• International Journal of Advanced Culture Technology
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• v.7 no.3
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• pp.52-57
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• 2019

This study is about the creation of a character art using the free association. Character in proposed artwork induces the viewer's unconscious experience associated with it and creates new meanings to invigorate the character. When a character that performs both a linguistic function and a visual image function goes through a free association process, the viewer can induce interest and convey the meaning of the character more effectively. We proposed two ways to express the dynamic movement of the character more actively. One is drawing using various colors and free lines, and the other is the movement of the character synchronized with the gesture of the viewer. As a result of implementing dynamic character art, we can see that the viewer was actively involved in the free association process and immersed in the artwork. The viewers participated in the creation of the artwork, changing the shape of the character according to their various gestures.