• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.21 no.2
• /
• pp.61-66
• /
• 2021

This paper related with the performance comparison of mSE-MMA and mDSE-MMA adaptive equalization algorithm which is possible to reduce the intersymbol interference that occurs in the nonlinear communication channel transmitting 16-QAM signal. This two algorithm is possible to reduce the computational load compared to the current MMA algorithm, it has the degraded equalization performance due to simplified arithmetic in order to applying the mobile communication terminal. In order to improve the performance degradation, they controls the step size according to the existence of arbitrary radius circle of equalizer output compared to transmitted symbol point. The variation of step size according to this principle is applied to the SE-MMA and DSE-MMA, namely mSE-MMA and mDSE-MMA algorithm, the algorithm's performance were compared in the same channel and noise environment by computer simulation. As a result of simulation, the mSE-MMA has more superior to the mDSE-MMA in residual value of every performance index and SER performance, and the vice versa result in convergence speed.

• Science of Emotion and Sensibility
• /
• v.24 no.1
• /
• pp.3-10
• /
• 2021

This study examined the effect of intentional thought avoidance(i.e., thought suppression and thought substitution) using "Think and No Think" task. Two syllable words were selected, and recall test was performed with a single subject group. recall accuracy of them was measured in two recall conditions(cue recall and target recall) and four training conditions(thought, thought suppression, thought substitution, and baseline). The results showed that recall accuracy in cue recall condition was better than in target recall condition, regardless of training conditions, and recall accuracy in thought condition was better than in other training conditions, regardless of recall conditions. Also there was significant interaction between recall and training conditions: For thought suppression. there was no difference between two recall conditions, whereas for thought substitution, recall accuracy in cue recall condition was better than in target condition. These findings indicate that thought avoidance strategies, including both thought suppression and thought substitution, are effective in avoiding the specific thought intentionally, and thought suppression and thought substitution could be applied by different mechanism.

• Journal of the Korea Computer Graphics Society
• /
• v.25 no.3
• /
• pp.31-41
• /
• 2019

A fog screen consists of tiny water drops and the viewers see the image transmitted through the fog screen. In contrast to ordinary screens, the viewers can see the actors passing through the image on the fog screen on stage. In this paper, we describe methods to build a top-down fog screen where fog particles generated in top space fall by gravity forming a flat vertical screen. We use a fog generation technique in which fog particles come out of the water surface when ultrasound vibrators immersed in water tank vibrate. We describe how fog particles form a flat screen while coming out of the fog passage tunnel, by generating guiding winds beside the fog screen. This technique utilizes the principle that fog particles are generated on the surface of a water tank by an ultrasonic vibrator placed in a water tank. The technique of forming a guiding wind on both sides of the passage exit where the fog comes out and the design and manufacturing method of the fog screen generating device are described so that the generated fog group can maintain one plane.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.394-397
• /
• 2014

Most of Koreans have smartphone. By using smartphone, they have done internet-banking, e-commerce and private scheduling. However, convenience of smart phone has been made side effect such as tool of fraud and crime. Especially, Smishing on smartphone has been increased rapidly since 2013. Smishing have utilized social-engineering technique with social issue such as Korean near-sea cruse ship, 'Sewol-Ho', Sinking and traditional thanks-giving holiday, 'Chu-Seok', etc. This paper proposed the oncoming trend of smishing on smartphone after 2014. This paper also analyzed the process and technique of smishing on internal financial fraud. It also covered smartphone forensic for using legal evidence. By discovering the connectivity of smishing and financial fraud, this paper could be reference for social security on smartphone.

• Journal of IKEEE
• /
• v.23 no.3
• /
• pp.805-810
• /
• 2019

We present a time-frequency analysis algorithm based on the multitaper method and the state-space frameworks. In general, time-frequency representations have a trade-off between the time duration and the spectral bandwidth by the uncertainty principle. To optimize the trade-off problems, the short-time Fourier transform and wavelet based algorithms have been developed. Alternatively, the authors proposed the state-space frameworks based on the multitaper method in the previous work. In this paper, we develop a real-time algorithm to estimate variances and spectrum using the state-space framework. We test our algorithm in spectral analysis of simulated data.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.1
• /
• pp.576-581
• /
• 2021

In the post-epidemic era, COVID-19 has not yet been fully controlled. Wearing masks is still the main means of epidemic prevention, and the negative effects brought by masks continue to continue. Wearing a mask for a long time can cause two problems. The first problem is hypoxia, and the other is an increase in psychological stress. To reduce the negative impact of masks, this paper proposes a new breathing mode. It is the "Umm~" vocal breathing mode, which simultaneously solves the two problems of hypoxia and increased stress. This paper explores the reasons why new breathing patterns can relieve stress. Explains the relationship between HRV and stress index and uses SDNN as an indicator to detect stress index to confirm the effectiveness of this breathing pattern. Experimental results prove that the "Umm~" vocal breathing mode can not only relieve the stress induced by wearing a mask. And when not wearing a mask, it can also be used to relieve daily stress. This method that anyone can easily implement should be more popularized.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.25 no.1
• /
• pp.51-58
• /
• 2021

As vertical extension remodeling policy was implemented in 2014, Safety Inspection Manual was established to ensure structural safety during the vertical extension remodeling. In the manual, the story weight for capability evaluation was based on the Safety Inspection Manual for Reconstruction. Although capability evaluation in the vertical extension remodeling is more important than reconstruction, engineering basis for the story weight is insufficient. Therefore it is necessary to improve the method of calculating the story weight. In this study, story importance and story weight were defined through the case analysis of capability evaluation in order to provide engineering basis for story weight. Also, new story weight equation was presented considering the load-bearing ratio of structural members.

• The Mathematical Education
• /
• v.60 no.3
• /
• pp.387-407
• /
• 2021

The present study was conducted on the assumptions that both progressivist and constructivist education emphasized the subjective knowledge of learners and confronted similar problems when the derived educational principles from the two perspectives were adopted and applied to mathematics research and practice. We argue that progressivism and constructivism should have clarified the meaning, purpose, and direction of 'emphasizing subjective knowledge' in application to the particular educational field. For the issue, we reflected Dewey's theory on the application of past progressivism, and aligned with it, we took a critical view of the educational applications of current constructivism. As a result, first, the meaning of emphasizing subjective knowledge is that each of the students constructs a unique mathematical reality based on his or her experience of situations and cognitive structures, and emphasizes our understanding of this subjective knowledge as researchers/observers. Second, the purpose of emphasizing subjective knowledge is not to emphasize subjective knowledge itself. Rather, it concerns the meaningful learning of objective knowledge: internalization of objective knowledge and objectification of subjective knowledge. Third, the application of the emphasis on subjective knowledge does not specify certain teaching/learning methods as appropriate, but orients us toward a genuine learner-centered reform from below. The introspections, we wish, will provide new momentum for discussion to establish constructivism as a coherent theory in mathematics classrooms.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.3
• /
• pp.399-408
• /
• 2022

This paper proposes a corrective control system to achieve fault-tolerant control for input/output asynchronous sequential circuits vulnerable to transient faults violating fundamental mode operations. To overcome non-fundamental mode faults occurring in transient transitions of asynchronous sequential circuits, it is necessary to determine the end of unauthorized state transitions caused by the faults and to stably take the circuit from the faulty state to a desired state that is output equivalent with the normal next stable state. We address the existence condition for a proper output-feedback corrective controller that achieves fault diagnosis and fault-tolerant control for these non-fundamental mode faults. The corrective controller and asynchronous sequential circuit are implemented on field-programming gate array to demonstrate the synthesis procedure and applicability of the proposed control scheme.

• Korean Journal of Construction Engineering and Management
• /
• v.23 no.1
• /
• pp.37-45
• /
• 2022

It is very important to measure the displacement of a structure to evaluate the safety of the structure. This study shows a methodology to measure the displacement to determine the stability of a structure when it is damaged by loads. The methodology used Moiré's phenomenon and was verified through experiments. The experiments utilized pipes to simulate the pipe supports in the construction site and measured the vertical displacement of the Moiré interference patterns according to the horizontal displacement of the pipes. Experiments confirmed that the linear relationship between horizontal displacement of pipes and vertical displacement of Moiré patterns and derive a relational expression. In conclusion, the methodology presented in this work allows us to simultaneously measure a number of vertical members' displacements regardless of distance and determine the safety of the structure.