• Journal of Microbiology and Biotechnology
• /
• v.31 no.6
• /
• pp.784-793
• /
• 2021

Previous studies have uncovered the role of circ_0000144 in various tumors. Here, we investigated the function and mechanism of circ_0000144 in gastric cancer (GC) progression. The expression of circ_0000144 in GC tissues and cells was detected through quantitative real-time polymerase chain reaction (qRT-PCR) method. Gain- and loss-of-function experiments including colony formation, wound healing and transwell assays were performed to examine the role of circ_0000144 in GC cells. Furthermore, western blot was conducted to determine the expressions of epithelial mesenchymal transition (EMT)-related proteins. The interaction between circ_0000144 and miR-217 was analyzed by bioinformatic analysis and luciferase reporter assays. The circ_0000144 expression was obviously upregulated in GC tissues and cells. Silencing of circ_0000144 inhibited cell proliferation, migration and invasion of GC cells, but ectopic expression of circ_0000144 showed the opposite results. Moreover, circ_0000144 sponged miR-217, and rescue assays revealed that silencing miR-217 expression reversed the inhibitory effect of circ_0000144 knockdown on the progress of GC. Our findings reveal that circ_0000144 inhibition suppresses GC cell proliferation, migration and invasion via absorbing miR-217, providing a new biomarker and potential therapeutic target for treatment of GC.

• Progress in Medical Physics
• /
• v.32 no.2
• /
• pp.50-58
• /
• 2021

Purpose: In this study, we investigated the relationship between the noise characteristics and the number of projected images in tomosynthesis using a digital phantom. Methods: The digital phantom consisted of a columnar phantom in the center of the image and a spherical phantom with a diameter of 80 pixels. A virtual scan was performed, and 128 projected images (Tomo_w/o) of the phantoms were obtained. The image noise according to the Poisson distribution was added to the projected images (Tomo_×1). Furthermore, another projected image with additional noise was prepared (Tomo_×1/2). For each dataset, we created datasets with 64 (half) and 32 (quarter) projections by removing the even-numbered images twice from the 128 (fully) projected images. Tomosynthesis images were reconstructed by filtered back projection (FBP). The modulation transfer function (MTF) was estimated using the sphere method, and the noise power spectrum (NPS) was estimated using the two-dimensional Fourier transform method. Results: The MTFs did not change between datasets, and the NPSs improved as the number of projected images increased. The noise characteristics of the Tomo_×1_half images were the same as those of the Tomo_×1/2_full. Conclusions: To achieve a reduction in the patient dose in tomosynthesis acquisition, we recommend reducing the number of projected images rather than reducing the dose per projection.

• Journal of Auto-vehicle Safety Association
• /
• v.14 no.3
• /
• pp.23-29
• /
• 2022

Among the various functions of ADAS (Advanced Driver Assistance System), the most important and representative function to the safety of vehicle passengers is AEB (Autonomous Emergency Braking system). In South Korea, laws are in progress from 2022 for making it mandatory for passenger vehicles to be installed. And as AEB-equipped vehicles continues to increase in the future, the demand for accident analysis related to the AEB function is expected to increase in the future. In order to find out the operating limits of AEB, it is necessary to consider the situations exceeding the standards covered by EuroNCAP. Therefore we have performed four experiments in this study, including situations encountered in real-word traffic conditions, i.e., an oblique stop of Global Vehicle Target (GVT) and ADAS sensor failures. These experimental results are expected to be of great help in accurate and reliable accident analysis by considering them when analyzing traffic accidents for ADAS vehicles.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.5
• /
• pp.63-68
• /
• 2022

Autonomous driving technology has recently made great progress with the introduction of deep reinforcement learning. In order to effectively use deep reinforcement learning, it is important to select the appropriate activation function. In the meantime, many activation functions have been presented, but they show different performance depending on the environment to be applied. This paper compares and evaluates the performance of 12 activation functions to see which activation functions are effective when using reinforcement learning to learn autonomous driving on highways. To this end, a performance evaluation method was presented and the average reward value of each activation function was compared. As a result, when using GELU, the highest average reward could be obtained, and SiLU showed the lowest performance. The average reward difference between the two activation functions was 20%.

• Journal of Korean Association for Spatial Structures
• /
• v.23 no.4
• /
• pp.97-105
• /
• 2023

The membrane structure should maintain the membrane materials in tension for structural stability guaranty. The anchoring part in the membrane structure is an important part. It has the function to introduce tension into membrane materials and function to transmit stress which membrane materials receives to boundary structure such as steel frames. In this paper, it grasps anchoring system of the anchoring part in the membrane structure concerning the fracturing characteristic condition of membrane structure, and the influence which is caused to yield it designates the stress state when breaking the membrane structure which includes the anchoring part and that stress transition mechanism is elucidated as purpose. This paper follows to previous paper, does 1 axial tensile test concerning the bolting part specimen, grasp of fracturing progress of the bolting part and the edge rope and hardness of the rubber, does the appraisal in addition with the difference of bolt tightening torque. As a result, the influence which the bolt anchoring exerts on the fracturing characteristics of the membrane material in the membrane structure anchoring part is examined.

• Proceedings of the KSME Conference
• /
• 2007.05b
• /
• pp.2678-2683
• /
• 2007

The interaction between metal molecules and liquid metal molecules was modeled in the molecular scale and simulated by the molecular dynamics method in order to understand behaviors of the cluster on metallic surface in collision process. Lennard-Jones potential had been used as intermolecular potential, and only attraction 때 d repulsion had been used for the behavior of the cluster on the metal surface. As results, the behavior of the cluster was so much influenced by the cluster of liquid metal temperature and function of molecules forces, such as attraction and repulsion, in the collision progress. These results of simulation will be the foundation for the micro fabrication manufacturing by using spray application technology.

• Herbal Formula Science
• /
• v.15 no.1
• /
• pp.145-161
• /
• 2007

Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with cutaneous hyperreactivity to environmental triggers. The clinical phenotype that characterizes AD is the product of interactions between susceptible genes, the environmental factors, defective skin barrier function, and immunologic responses. This review summarizes recent progress in our understanding of the immunopathophysiology of AD and the implications for mouse models of AD in drug discovery from medicinal plants.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2000.10a
• /
• pp.432-439
• /
• 2000

According as ground acceleration becomes to exceed gravity acceleration recently, design is impossible or economical efficiency is poor in existing seismic design method. So increase of seismic isolated bridges is currently in progress. However, because base isolation design method is developed in high seismic regions. it may not be compatible in Korea. Therefore, this research has objective to evaluate ductility of pier and response modification factor according to the ductility of pier in seismic isolated bridges and to adapt to seismic characteristics in Korea. For this purpose, nonlinear analysis is accomplished with so many time histories derived from spectral density function compatible with response spectrum described in the design code and base isolation system modeled linear system, bi-linear system, and friction system. Through application of the proposed method, we had result that it may be compatible that response modification factor for the seismic isolated bridges is smaller than half of that for the conventional bridges when natural period of structures exceeds proper level.

• The Journal of Information Technology
• /
• v.8 no.1
• /
• pp.83-93
• /
• 2005

This paper again to present position of a bus that is running in bus government organization small grasp and Can instruct control about the vehicles progress speed in government organization small to bus driver. Therefore, Inform a bus that own wants to ordinary people who carry transfer communication terminal is situated to where present, ad Do by purpose that offer system that inform running information of a bus to ARS and FAX, internet and ordinary people through PC communication. Also, Intelligence style bus control system that see also includes function that do as can guide arrival expectation depot automatically without driver's manufacturing when run a bus.

• Tunnel and Underground Space
• /
• v.7 no.1
• /
• pp.13-19
• /
• 1997

It is necessary to study on thermo-hydro-mechanical effect at rock mass performing project such as radiowaste disposal in deep rock mass. In this study, thermo-hydro-mechanical coupling analysis which is considered interaction and the variation of rock properties induced by temperature increase was performed for the circular shaft when appling temperature of 20$0^{\circ}C$ at the shaft wall. The shaft is diameter of 2 m and under hydrostatic stress of 5 MPa. In the cases, thermal expansion by temperature increase progress from the wall to outward and thermal expansion could induce tensile stress over the tensile strength of rock mass at the wall. When rock properties were given as a function of temperature, thermal expansion increased, tensile stress zone expanded. Lately, water flow is activated by increase of permeability and decrease of viscosity.