• Journal of IKEEE
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• v.26 no.3
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• pp.355-363
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• 2022

Korea is pursuing a plan to switch and expand energy sources with a focus on renewable energy with the goal of becoming carbon neutral by 2050. As the instability of energy supply increases due to the intermittent nature of renewable energy, accurate prediction of the amount of renewable energy generation is becoming more important. Therefore, the government has opened a small-scale power brokerage market and is implementing a system that pays settlements according to the accuracy of renewable energy prediction. In this paper, a prediction model was implemented using a statistical model and an artificial intelligence model for the prediction of solar power generation. In addition, the results of prediction accuracy were compared and analyzed, and the revenue from the settlement amount of the renewable energy generation forecasting system was estimated.

• Journal of IKEEE
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• v.26 no.3
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• pp.364-372
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• 2022

This paper proposes the design and implementation results for human and object classification systems utilizing frequency modulated continuous wave (FMCW) radar sensor. Such a system requires the process of radar sensor signal processing for multi-target detection and the process of deep learning for the classification of human and object. Since deep learning requires such a great amount of computation and data processing, the lightweight process is utmost essential. Therefore, binary neural network (BNN) structure was adopted, operating convolution neural network (CNN) computation in a binary condition. In addition, for the real-time operation, a hardware accelerator was implemented and verified via FPGA platform. Based on performance evaluation and verified results, it is confirmed that the accuracy for multi-target classification of 90.5%, reduced memory usage by 96.87% compared to CNN and the run time of 5ms are achieved.

• Journal of Industrial Convergence
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• v.20 no.10
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• pp.39-49
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• 2022

The purpose of this study was to systematic review about randomized controlled trials the characteristics and effect of non-pharmacological intervention on depressive symptom in elderly with mild cognitive impairment. We searched studies published from January 2011 to July 2021 in 3 databases. A total 1,455 studies were found and included 11 studies in final analysis. Methodological quality was assessment with the Cochrane's RoB(risk of bias) tool. Geriatric Depression Scale(GDS) was the most used as the assessment tool for identifying the depressive symptom. Intervention were yoga, psychosocial intervention, cognitive training, health education, multi-component intervention, game training, aerobic/pulmonary physiotherapy, art therapy, music reminiscence activity, memory specificity training, cognitive stimulation therapy and SWTW(sleep well, think well) program. Among the intervention programs, yoga, multi-component intervention and game training were effective in improving depressive symptom. This study provided a clinical evidence for planning and implementing intervention on depressive symptom in elderly with mild cognitive impairment.

• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.191-200
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• 2022

Constrained Application Protocol (CoAP) is a standardized protocol by the Internet Engineering Task Force (IETF) for the Internet of things (IoT). IoT devices have limited computation power, memory, and connectivity capabilities. One of the significant problems in IoT networks is congestion control. The CoAP standard has an exponential backoff congestion control mechanism, which may not be adequate for all IoT applications. Each IoT application would have different characteristics, requiring a novel algorithm to handle congestion in the IoT network. Unnecessary retransmissions, and packet collisions, caused due to lossy links and higher packet error rates, lead to congestion in the IoT network. This paper presents an adaptive congestion control protocol for CoAP, Adaptive Congestion Control with a Backoff algorithm (ACCB). AACB is an extension to our earlier protocol AdCoCoA. The proposed algorithm estimates RTT, RTTVAR, and RTO using dynamic factors instead of fixed values. Also, the backoff mechanism has dynamic factors to estimate the RTO value on retransmissions. This dynamic adaptation helps to improve CoAP performance and reduce retransmissions. The results show ACCB has significantly higher goodput (49.5%, 436.5%, 312.7%), packet delivery ratio (10.1%, 56%, 23.3%), and transmission rate (37.7%, 265%, 175.3%); compare to CoAP, CoCoA+ and AdCoCoA respectively in linear scenario. The results show ACCB has significantly higher goodput (60.5%, 482%,202.1%), packet delivery ratio (7.6%, 60.6%, 26%), and transmission rate (40.9%, 284%, 146.45%); compare to CoAP, CoCoA+ and AdCoCoA respectively in random walk scenario. ACCB has similar retransmission index compare to CoAp, CoCoA+ and AdCoCoA respectively in both the scenarios.

• Journal of Audiology & Otology
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• v.24 no.4
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• pp.167-173
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• 2020

Background and Objectives: Top-down restoration of distorted speech, tapped as phonemic restoration of speech in noise, maybe a useful tool to understand robustness of perception in adverse listening situations. However, the relationship between phonemic restoration and speech perception in noise is not empirically clear. Subjects and Methods: 20 adults (40-55 years) with normal audiometric findings were part of the study. Sentence perception in noise performance was studied with various signal-to-noise ratios (SNRs) to estimate the SNR with 50% score. Performance was also measured for sentences interrupted with silence and for those interrupted by speech noise at -10, -5, 0, and 5 dB SNRs. The performance score in the noise interruption condition was subtracted by quiet interruption condition to determine the phonemic restoration magnitude. Results: Fairly robust improvements in speech intelligibility was found when the sentences were interrupted with speech noise instead of silence. Improvement with increasing noise levels was non-monotonic and reached a maximum at -10 dB SNR. Significant correlation between speech perception in noise performance and phonemic restoration of sentences interrupted with -10 dB SNR speech noise was found. Conclusions: It is possible that perception of speech in noise is associated with top-down processing of speech, tapped as phonemic restoration of interrupted speech. More research with a larger sample size is indicated since the restoration is affected by the type of speech material and noise used, age, working memory, and linguistic proficiency, and has a large individual variability.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.3
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• pp.1-11
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• 2022

Purpose: This place, which is currently becoming an issue due to historical preservation and landscape protection, is also a place where urban residents around Taereung actually visit often. Thus, this study aims to analyze the importance of the evaluating factors in creating a relatable image of the city. Methods: Evaluation items were selected by reviewing related books and research literatures and reassessing the reviewed items through an expert group interview (FGI). For the selected evaluation items, the relative importance of the evaluation items for the place image was analyzed by applying the hierarchical analysis technique (AHP) to each user group. Result: A place becomes a memory in people's experiences and time, and it has the image and identity of the region where those experiences and memories are found again as a space called "place". The method of analyzing the importance of evaluation items between place images used in this study quantified the factors recognized as abstract images and identified the degree of influence between elements, but has limitation in that it targeted specific places. However, the analysis method on the place image recognition suggests the use of itemized variables for characteristics between place images, so future research on the identity of other place images can be conducted together. Also, the evaluation method of the image that recognizes the place has an objective meaning in that it can measure the image of the place quantitatively. In the future, it can be applied in creating an image forming factor or urban identity for place recognition in many regions

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1142-1147
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• 2022

The edges of image should be detected first so that the objects in the image can be identified. An hardware-implemented edge detection algorithm outperforms its software version. Sobel operation is the most suitable algorithm for an hardware implementation of edge detection. And lots of works have been done to perform Sobel operations efficiently on FPGA-based hardware. This work proposes how to implement fast edge detection circuit on FPGA, which is based on the conventional circuit for edge detection using Sobel operator. The newly proposed circuit is suitable for processing images when the images are stored in memory devices and outperforms the conventional one with little additional FPGA resources. Both the conventional circuit and the proposed circuit were implemented on an FPGA. And the result showed that the proposed circuit almost doubles the performance in processing images and needs little additional FPGA resources.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1196-1204
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• 2022

In this paper, we propose an optimization algorithm that maximizes the network lifetime in wireless ad-hoc networks using the broadcast transmission method. The optimization algorithm proposed in this paper applies tabu search algorithm, a metaheuristic method that improves the local search method using the memory structure. The proposed tabu search algorithm proposes efficient encoding and neighborhood search method to the network lifetime maximization problem. By applying the proposed method to design efficient broadcast routing, we maximize the lifetime of the entire network. The proposed tabu search algorithm was evaluated in terms of the energy consumption of all nodes in the broadcast transmission occurring in the network, the time of the first lost node, and the algorithm execution time. From the performance evaluation results under various conditions, it was confirmed that the proposed tabu search algorithm was superior to the previously proposed metaheuristic algorithm.

• Journal of architectural history
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• v.31 no.3
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• pp.41-52
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• 2022

This study explains the han-ok. in Gae-sung, which was antique and traditional city. In view of the fact that these were located in Gae-sung in North Korea hence direct investigate is not possible. Since there was no comprehensive study of Gaeseong han-ok, we have no choice but to rely on fragmentary records and memory of Gaeseong people. In accordance from the Japanese colonial era's surveys and sketches as well as how they were illustrated in the novel. Hark back to the peoples' thought of the han-ok years when they ran the survey in 1920s, the results were as follows: First, there are many houses so various classes in Mi-Mang. Jeon Cheo-man's house was a representative example of a rich family in Gae-sung, Jeon Je-seong(Jeon's 2^nd son)'s house was located in Si-jeon(government licensed-markets) near by the South gate. In particular, Jeon Yi-seong(Jeon's 3rd son)'s house was in rural areas. He managed on immense ginseng field and worker's houses. Hae-ju's house was a small house off the track. Second, the outer house is low and the main house is high and neat. Lastly, it was confirmed that it corresponded to sketches recorded by architects, such as neat housekeeping, long stones used for various purposes, invisible flat gates, the appearance of old and old houses and the composition of each room.

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.348-358
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• 2022

The purpose of this study is to produce visual content for effective education of Passive verbs and Causative verbs in Korean language education for foreigners. Passive verbs and causative verbs are contents that must be taught to intermediate level learners. However, it is recognized as a difficult item for both learners and Korean teachers because the realization pattern is complicated, and there is no rule to explain the combination relationship between the action and the instruction by suffix. In this article, the use of nonverbal information that can improve the learning effect was considered. Providing verbal and non-verbal information together in language education can be expected to improve learners' communication skills. In particular, visual content is non-verbal information that can positively affect memory enhancement, playback, and transition. Therefore, this study attempted to plan and produce picture cards as visual materials. The picture card, produced with a focus on the correct education of Korean Passive verbs, will efficiently and significantly make Korean Passive verbs and Causative verbs teaching and learning by suffixes.