• Journal of Ceramic Processing Research
• /
• v.20 no.5
• /
• pp.484-489
• /
• 2019

VO2 is an attractive candidate as a transition metal oxide switching material as a selection device for reduction of sneak-path current. We demonstrate deposition of nanoscale VO2 thin films via thermal atomic layer deposition (ALD) with H2O reactant. Using this method, we demonstrate VO2 thin films with high-quality characteristics, including crystallinity, reproducibility using X-ray diffraction, and X-ray photoelectron spectroscopy measurement. We also present a method that can increase uniformity and thin film quality by splitting the pulse cycle into two using scanning electron microscope measurement. We demonstrate an ON / OFF ratio of about 40, which is caused by metal insulator transition (MIT) of VO2 thin film. ALD-deposited VO2 films with high film uniformity can be applied to next-generation nonvolatile memory devices with high density due to their metal-insulator transition characteristic with high current density, fast switching speed, and high ON / OFF ratio.

• Journal of The Korean Society of Integrative Medicine
• /
• v.12 no.2
• /
• pp.111-119
• /
• 2024

Purpose : This study aimed to demonstrate the effects of visiting cognitive activities using brain training on cognition, subjective memory complaints and depression among elderly participants residing in community living in Gwangmyeong city. Methods : Over a 14-month period (October 2022 to December 2023), four brain training instructors visited the homes of older adults and conducted the intervention using a brain training kit. The participants included 32 elderly individuals aged 65 years and older, who were living in Gwangmyeong city. The assessments were conducted by an occupational therapist, a nurse and a social worker at the Gwangmyeong dementia relief center. These assessments included the following the subjective memory complaints questionnaire (SMCQ), short geriatric depression scale-Korean (SGDS-K), a cognitive impairment screening test (CIST), the consortium to establish a registry for Alzheimer's disease-Korean (CERAD-K). The participants were divided into three groups (A: 20-30 points, B: 10-19 points, C: 1-9 points) based on the CIST score. For data analysis, descriptive statistics and wilcoxon signed-rank test were performed using SPSS 24.0, and the statistical level was at a=.05. Results : The results of the intervention showed that the SMCQ score of group A improved significantly (p<.05), the CIST score of group B also improved significantly (p<.05). However, the SGDS-K score of group C improved, but did not demonstrate statistical significance (p=.080). Conclusion : The visiting cognitive activities using brain training produced significant effects on cognition, depression, and subjective memory disorders, depending on the cognitive level of the elderly participants. In the future, it will be necessary to demonstrate the effects according to cognitive level in various aspects with more elderly people.

• Structural Engineering and Mechanics
• /
• v.90 no.6
• /
• pp.611-633
• /
• 2024

This study intends to investigate the response of multi-cell (MC) beams to flexural loads in which the primary reinforcement is composed of both metallic and non-metallic materials. "Multi-cell" describes beam sections with multiple longitudinal voids separated by thin webs. Seven reinforced concrete MC beams measuring 300×200×1800 mm were tested under flexural loadings until failure. Two series of beams are formed, depending on the type of main reinforcement that is being used. A control RC beam with no openings and six MC beams are found in these two series. Series one and two are reinforced with metallic and non-metallic main reinforcement, respectively, in order to maintain a constant reinforcement ratio. The first crack, ultimate load, deflection, ductility index, energy absorption, strain characteristics, crack pattern, and failure mode were among the structural parameters of the beams under investigation that were documented. The primary variables that vary are the kind of reinforcing materials that are utilized, as well as the kind and quantity of mesh layers. The outcomes of this study that looked at the experimental and numerical performance of ferrocement reinforced concrete MC beams are presented in this article. Nonlinear finite element analysis (NLFEA) was performed with ANSYS-16.0 software to demonstrate the behavior of composite MC beams with holes. A parametric study is also carried out to investigate the factors, such as opening size, that can most strongly affect the mechanical behavior of the suggested model. The experimental and numerical results obtained demonstrate that the FE simulations generated an acceptable degree of experimental value estimation. It's also important to demonstrate that, when compared to the control beam, the MC beam reinforced with geogrid mesh (MCGB) decreases its strength capacity by a maximum of 73.33%. In contrast, the minimum strength reduction value of 16.71% is observed in the MC beams reinforced with carbon reinforcing bars (MCCR). The findings of the experiments on MC beams with openings demonstrate that the presence of openings has a significant impact on the behavior of the beams, as there is a decrease in both the ultimate load and maximum deflection.

• Journal of the Optical Society of Korea
• /
• v.17 no.2
• /
• pp.136-141
• /
• 2013

A method to determine the transverse magnification (TM) of an imaging system is discussed. This method is different in that TM can be determined accurately by using distortion analysis. We demonstrate the validity of the method via numerical simulation with accompanying experimental data for a thick bi-convex lens.

• Honam Mathematical Journal
• /
• v.28 no.1
• /
• pp.165-183
• /
• 2006

In this article, we try to show that concepts and principles in probability can be taught vividly through the use of the Monte Carlo method to students who have difficulty with probability in the classrooms. We include some topics to demonstrate the application of a wide variety of real world problems that can be addressed.

• Proceedings of the IEEK Conference
• /
• 1998.10a
• /
• pp.1297-1300
• /
• 1998

In this paper, we discuss the identification of a chaotic system using chaotic neural networks. Because of selfconnections in neuron itself and interconnections between neurons, chaotic neural networks identifiers show good performance in highly nonlinear dynamics such as chaotic system. Simulation results are presented to demonstrate robustness of chaotic neural networks identifier.

• Proceedings of the Optical Society of Korea Conference
• /
• 1990.02a
• /
• pp.121-125
• /
• 1990

Optical Hough transform technique is introduced to obtain the straight line features in parallel from the input scene images. Experimental results are also provided to demonstrate the advantage of such optical parallel processor over the digital one. Peaks in optical Hough space are free from quantization noise and thus easy to detect.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1999.10a
• /
• pp.495-498
• /
• 1999

This paper examines a diagnostic model based on the concept of rule and fuzzy pattern recognition. One example is presented to demonstrate the feasibility of the model in diagnosing crack formations in reinforced concrete structures and the result by the expert system is generally satisfactory

• Proceedings of the Korean Society of Computational and Applied Mathematics Conference
• /
• 2003.09a
• /
• pp.8.1-8
• /
• 2003

We prove that m-step walks and self-avoiding walks on the 2D triangle lattices can be uniquely characterized (canonized) with no more than m Euclidian distances. We also demonstrate that these canonical distances can be obtained with O(n) physical measurements.

• Journal of KSNVE
• /
• v.4 no.1
• /
• pp.59-69
• /
• 1994

A new LMS algorithm titled constrained LMS' is proposed for problems with constrained structure. The conventional LMS algorithm can not be used because it destroys the constrained structures of the weights or parameters. Proposed method uses error-back propagation, which is popular in training neural networks, for error minimization. The illustrative examplesare shown to demonstrate the applicability of the proposed algorithm.