• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.199-206
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• 1991

A statistical thermodynamic theory of thermotropic main-chain polymeric liquid crystalline melts is developed within the framework of the lattice model by a generalization of the well-known procedure of Flory and DiMarzio. According to the results of Vasilenko et al., the theory of orientational ordering in melts of polymers containing rigid and flexible segments in the main chain is taken into account. When the ordering of flexible segments in the nematic melt is correlated with that of rigid mesogenic groups, the former is assumed to be given as a function of the ordering of rigid mesogenic cores. A free energy density that includes short-range packing contributions is formulated. The properties of the liquid-crystalline transiton are investigated for various cases of the system. The results calculated in this paper show not only the order-parameter values but also the first-order phase transition phenomena that are similar to those observed experimentally for the thermotropic liquid-crystalline polymers and show the transitional entropy terms which actually increase upon orientational ordering. In the orientational ordering values, it is shown that mesogenic groups, flexible segments, and gauche energy (temperature) may be quite substantial. Finally, by using the flexibility term, we predict the highly anisotropic mesophase which was shown by Vasilenko et al.

• Steel and Composite Structures
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• v.38 no.6
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• pp.705-716
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• 2021

An innovative partially precast partially encased composite beam (PPECB) is put forward based on the existing research. In order to study the flexural performance of the new composite beam which has precast part and cast-in-place part, six prefabricated specimens and one cast-in-place specimen are designed with considering the influence of the production method, the steel flange thickness, the concrete strength grade and the stirrup process on the behavior of the composite beam. Through four points loading and test data collection and analysis, the behavior of partially prefabricated specimen is similar to that of cast-in-place specimen, and the casting method, the thickness of the steel flange, the concrete strength grade and the stirrup process have different influence on the crack, yield and peak load bearing capacity of the component. Finally, the calculation theory of plastic bending of partially precast partially encased concrete composite beams is given. The calculation results are in good agreement with the experimental results, which can be used for practical engineering theory guidance. This paper can provide reference value for further research and engineering application.

• Journal of Information Technology Services
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• v.20 no.5
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• pp.29-41
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• 2021

The spread of COVID-19 has been changed the tourism industry. Travelers changed their traveling style and started to consider congestion of the spot for their health and safety. In Jeju, a famous tourist destination in South Korea, managing the congestion of tourists has become an important issue. This example introduces the Jeju Tourism Organization's development of a system as a smart tourism information service that manages congestion in real-time big data. Combining with congestion theory and behavior immune system, we would like to assure the necessity of the system. Also, by analyzing the system, we understand how deducing congestion information from big data and the new paradigm of the tourism industry combined with congestion theory. Data was collected by Korea's telecommunication company SKT to develop the system. The paper explains the reason for choosing the company and the pros of data quality. We expect this system to be a solution for any other city in the world under a similar situation. Finally, several suggestions for the system are included to promote and better future usage.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.1
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• pp.211-230
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• 2022

In image segmentation, for the condition that objects (targets) and background in an image are intertwined or their common boundaries are vague as well as their textures are similar, and the targets in images are greatly variable, the deep learning might be difficult to use. Hence, a new method based on graph theory and guided feathering is proposed. First, it uses a guided feathering algorithm to initially separate the objects from background roughly, then, the image is separated into two different images: foreground image and background image, subsequently, the two images are segmented accurately by using the improved graph-based algorithm respectively, and finally, the two segmented images are merged together as the final segmentation result. For the graph-based new algorithm, it is improved based on MST in three main aspects: (1) the differences between the functions of intra-regional and inter-regional; (2) the function of edge weight; and (3) re-merge mechanism after segmentation in graph mapping. Compared to the traditional algorithms such as region merging, ordinary MST and thresholding, the studied algorithm has the better segmentation accuracy and effect, therefore it has the significant superiority.

• Journal of Ocean Engineering and Technology
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• v.36 no.1
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• pp.11-20
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• 2022

Generally, tsunamis are generated by the rapid crustal movements of the ocean floor. Other factors of tsunami generation include landslides on coastal and ocean floor slopes, glacier collapses, and meteorite collisions. In this study, two numerical analyses were conducted to examine the formation, propagation, and deformation properties of landslide tsunamis. First, LS-DYNA was adopted to simulate the formation and propagation processes of tsunamis generated by dropping rigid bodies. The generated tsunamis had smaller wave heights and wider waveforms during their propagation, and their waveforms and flow velocities resembled those of theoretical solitary waves after a certain distance. Second, after the formation of the landslide tsunami, a tsunami based on the solitary wave approximation theory was generated in a numerical wave tank (NWT) with a computational domain that considered the stability/steady phase. The comparison of two numerical analysis results over a certain distance indicated that the waveform and flow velocity were approximately equal, and the maximum wave pressures acting on the upright wall also exhibited similar distributions. Therefore, an effective numerical model such as LS-DYNA was necessary to analyze the formation and initial deformations of the landslide tsunami, while an NWT with the wave generation method based on the solitary wave approximation theory was sufficient above a certain distance.

• Structural Engineering and Mechanics
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• v.85 no.6
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• pp.765-780
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• 2023

In this work, a novel combined logarithmic, secant and tangential 2D and quasi-3D refined higher order shear deformation theory is proposed to examine the buckling analysis of simply supported uniform functionally graded plates under uniaxial and biaxial loading. The proposed formulations contain a reduced number of variables compared to others similar solutions. The combined function employed in this study ensures automatically the zero-transverse shear stresses at the free surfaces of the structure. Various models of the material distributions are considered (linear, quadratic, cubic inverse quadratic and power-law). The differentials stability equations are derived via virtual work principle with including the stretching effect. The Navier's approach is applied to solve the governing equations which satisfying the boundary conditions. Several comparative and parametric studies are performed to illustrates the validity and efficacity of the proposed model and the various factors influencing the critical buckling load of thick FG plate.

• Journal of East-West Nursing Research
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• v.29 no.1
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• pp.1-5
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• 2023

Traditional Korean medicine and traditional Korean (Hanbang) nursing are very similar disciplines in terms of philosophy, values, and identity. Traditional Korean medicine views that harmonious and balanced human body and mental state can be formed through the flow of Qi and blood using meridians and acupressure points. This view can be applied to research, practice, theory, and education in Hanbang nursing. The meridian is a pathway through which Qi and blood, the energy necessary for life activities, pass through. Acupressure points are important meridians where physical, mental, and psychological health conditions appear as a response. Pressing and stimulating acupressure points to facilitate and communicate the flow of qi and blood in the meridians can create positive effects and enable the treatment of various symptoms and syndromes of our bodies. Hanbang nursing nursing, which is also based on the use of meridians, may be used to control various symptoms and syndromes and prevent and treat diseases. Currently, Hanbang nursing are growing along with the professionalism of Hanbang nursing practice, vitalization of Hanbang nursing research, and the development of Hanbang nursing education and theory. The growth of Hanbang nursing requires active participation of nursing scholars and efforts to converge beyond the walls of medicine and nursing.

• Journal of Korean Medical classics
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• v.36 no.2
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• pp.1-22
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• 2023

Objectives : In order to understand and apply Lee Jema's emotion control method, the basic concepts of his nature-temperament theory was examined. Lee's thoughts on emotion control, and the basic principles of his method were deduced from this process. Methods : The meaning and set-up of basic concepts in his nature-temperament theory as written in text such as the Donguisusebowon, Gyeokchigo, and Donguisusebowon Sasang Chobongwon were examined, and compared with similar concepts of Confucianism. Results & Conclusions : Out of concepts set by Lee, the Ae(哀)-No(怒)-Hui(喜)-Rak(樂) nature-temperament is the condition for emotion control. Junghwa(中和) is the aim of emotion control according to different stages of emotional expression, and Jiin(知人) is the precondition for emotion control. Lee's basic principles of emotion control could be summarized as following. First, it must be done with the aim for 'Goodness[善]' to be manifested. Second, it must be based on clear understanding of 'Insa(人事)'. Lastly, Hoyeonjigi(浩然之氣) and Hoyeonjiri(浩然之理) must be consistently cultivated for stable emotion control.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.1
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• pp.25-34
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• 2022

Established and new companies face similar business challenges in achieving performance and competitiveness. Furthermore, several empirical studies using competitive advantage resource-based view theory show that established companies achieve performance and competitiveness with breakthrough innovations. Similarly, new business ventures with limited resources must incorporate breakthrough innovations to achieve performance and competitiveness. Therefore, this study aimed to examine the impact of ambidextrous innovation on new venture performance and competitiveness. It used an online survey to collect data from 178 newly established shipping agency companies in 22 provinces in Indonesia. Data was analyzed using multivariate analysis with WarpPLS 7.0, where the analysis unit was an organization represented by a director. The results showed that ambidextrous innovation positively and significantly affects firm performance and new venture competitiveness. This means that ambidextrous innovation that emphasizes adaptation and development improves the firm's internal business processes, even with limited resources. Moreover, it increases new ventures' competitiveness in responding to threats and taking advantage of market opportunities. These results contribute to the competitive advantage resource-based view theory, specifically for new venture empirical examination. Also, they contribute to practical implications in the transportation business, demonstrating that exploitative breakthrough innovation can improve new venture competitiveness and performance.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.6
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• pp.51-63
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• 2023

To improve the problem that the settlement curve of the consolidation theory of Terzaghi does not match well with the actual settlement curve, we included a secondary compression settlement and analyzed it by varying the beginning point and then obtained the following results. The current methods of calculating the compression index from the  log𝜎 curve and the coefficient of consolidation from the time-dependent settlement curve for each consolidation pressure proved that the final settlement amount will be consistent after a long time, but the actual settlement amount will always be smaller than the predicted settlement amount during the settlement progress stage. The consolidation factors estimated by the curve fitting with the condition that the secondary compression begins in the second half of the primary compression showed similar values to the consolidation factors estimated by the curve fitting for the primary compression only, and the settlement curves were in better agreement throughout the compression. It showed different values, showing low validity. It can be inferred that secondary compression acts from the point when a significant portion of the excess pore water pressure is dissipated, and the loading stress begins to have more influence on the skeletal structure of the soil. Analysis results show that secondary compression begins at the range of 91 % to 98 % on the average degree of primary consolidation.