• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.2
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• pp.76-83
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• 2022

Since the 3D printing mortar is exposed to the atmosphere immediately after printing, moisture is largely evaporated from the surface of the layer. The evaporation of moisture on the surface of the layer greatly causes drying shrinkage and increases the risk of cracking and damage to the structure due to drying shrinkage. This study experimentally evaluated the shrinkage behavior of the initial age using the mortar used for 3D printing. The change in shrinkage was evaluated by comparing the shrinkage of the specimen cured by the sealing method and the atmospheric exposure method. In addition, compared with the case where type 1 cement was used 100%, the shrinkage amount was evaluated when 20% of fly ash was replaced and 10% of silica fume was used. In particular, the effect of three chemical admixtures applied using 3D printing on shrinkage was evaluated experimentally. When fly ash and silica fume were used, the shrinkage amount increased by 60 - 110% compared to the case when type 1 cement was used. The application of viscosity modifiers and shrinkage reducers reduced the shrinkage by at least 18% and at most 70% depending on the curing conditions. The temperature of the specimen temporarily decreased to 15 ℃ at the beginning of curing, and the correlation between the internal temperature of the specimen and the shrinkage behavior was observed.

• KIPS Transactions on Software and Data Engineering
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• v.11 no.7
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• pp.291-298
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• 2022

In this paper, we present a method for dependency parsing with chunking in Korean. Dependency parsing is a task of determining a governor of every word in a sentence. In general, we used to determine the syntactic governor in Korean and should transform the syntactic structure into semantic structure for further processing like semantic analysis in natural language processing. There is a notorious problem to determine whether syntactic or semantic governor. For example, the syntactic governor of the word "먹고 (eat)" in the sentence "밥을 먹고 싶다 (would like to eat)" is "싶다 (would like to)", which is an auxiliary verb and therefore can not be a semantic governor. In order to mitigate this somewhat, we propose a Korean dependency parsing after chunking, which is a process of segmenting a sentence into constituents. A constituent is a word or a group of words that function as a single unit within a dependency structure and is called a chunk in this paper. Compared to traditional dependency parsing, there are some advantage of the proposed method: (1) The number of input units in parsing can be reduced and then the parsing speed could be faster. (2) The effectiveness of parsing can be improved by considering the relation between two head words in chunks. Through experiments for Sejong dependency corpus, we have shown that the USA and LAS of the proposed method are 86.48% and 84.56%, respectively and the number of input units is reduced by about 22%p.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.251-258
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• 2022

Donghae Port is adjacently located to a residential area wherein 26,933 generations are creating a living environment. The areas comprise Song-jeong village (5,754 generations) and Bukp-yeong village (21,179 generations). Major cargoes handled in Donghae Port are dusty limestone, cement, anthracite, and bituminous coal, etc. In the process of handling such cargoes, air pollutants including oxide dust and fine dust which adversely impact the living conditions and health of residents are generated, causing air pollution in the vicinity of the port. Currently, Donghae Port is making an effort to improve the operation environment of the infrastructure and equipment in stages, for the purpose of reducing air pollutant emissions caused by the port industries in a long-term perspective. In this study, the sphere of influence of fine dust exposure and the degree of air pollution in the surrounding area were analyzed such as the state of fine dust concentration and diffusion in the vicinity of Donghae Port, fine dust diffusion pattern and spatial distribution of high-concentration considering wind direction and speed characteristics during the day and seasonal cycles. A more effective plan to reduce the concentration of fine dust in nearby areas by combining reduction plan, is being developed in terms of improvement regarding port infrastructure and equipment, and reduction measures considering the characteristics of the atmosphere environment according to the daytime, nighttime and season.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.493-499
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• 2022

The standards pertaining to the quality of discharged water in sewage treatment plants are strengthening, and accordingly, facilities in sewage treatment plants are being upgraded. In addition, the discharge water quality of sewage treatment plants must be maintained at a high level, and efficient sewage treatment plant operations have thus emerged as a very important issue. For the efficient operation of sewage treatment plants, this study applied a basic blowing amount calculation method based on sewage facilities to evaluate the required oxygen amount and blowing amount according to inflow water quality by logicizing various influencing factors. As a result of calculating the amount of air blown by applying actual April water quality data from sewage treatment plant A to the blower demand calculation developed through this study, it was found that the average amount of air blown was reduced by about 12%. When the blower demand calculation developed here is applied to an actual sewage treatment plant, the amount of air blown can be controlled based on the inflow water quality. This can facilitate the realization of an autonomous control of sewage treatment plants, in contrast to the existing sewage treatment operation method that relies on operational experience of operator. In addition, it is expected that efficient sewage treatment plants can be operated by reducing blowing amounts and power costs, which will contribute to both energy and carbon savings.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.69-77
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• 2022

Physical experiment through MBL has been used in many schools for a long time since students can check the experiment results immediately and conduct the experiment easily. However, conducting the experiment, not knowing the principle of the device or simply concentrating on the derived data has been raised as the problem of MBL experiment. To supplement this problem, this study measured the acceleration of gravity with the picket fence method, which is often used in MBL experiment, utilizing Arduino, calculated the error rate through a comparison to the actual acceleration of gravity and discussed the educational application of the experiment to measure it. As a result of the experiment, the error rate between the acceleration of gravity calculated by the experiment and the actual acceleration of gravity was about 1%, so it turned out that relatively accurate measurements were possible. Also, the sample mean of the experimental value was included in the confidence interval of 95%, so it could be concluded that it was a significant experiment. In addition, this study showed the possibility of the educational application of the experiment to measure it through the following: It can supplement the structural disadvantages of MBL; it can consider the interaction between Physics and Math; it is possible to converge with information course in STEAM education; and it is inexpensive to be equipped with the equipment. Hopefully, the physical experiment utilizing Arduino will further be revitalized in science gifted education based on this study.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.63-72
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• 2022

With the advent of cryptocurrencies such as Bitcoin in 2009, the paradigm of money, a means of payment, has been changing significantly. And it has a great impact on our daily lives. Thus central banks have attempted various analyzes on the issuance and impact of digital currencies including electronic payments but a study on which issuance method is suitable is insufficient. In this study, the issuance of digital currency was analyzed compared to the electronic payments which are currently used. As a result, the account-based model did not show any significant differences from the current RTGS(real-time gross settlement systems) and retail payment systems. But the token-based model is expected that it can improve the efficiency of finance and induce technological innovation in the financial field. However, it was analyzed that this model would weaken the intermediary function of financial institutions such as loans due to the characteristics of digital signature technology. In addition, in order to protect consumers against security attacks such as hacking and phishing of CBDCs, legal and institutional supports similar to the current electronic payment method are required, and continuous technology development efforts are also required for the CBDC issuance model to maintain convenience and anonymity equivalent to cash.

• Journal of Music and Human Behavior
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• v.19 no.1
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• pp.93-112
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• 2022

The purpose of this study was to compare participants' perceived emotion following harmonic changes in music. In this study, 144 participants, aged 19 to 29 years, listened to music online that included low to high harmonic progression in tonal music (major-minor). After listening to each piece of music, participants were asked to rate 4 items using a 7-point Likert scale: emotional potency, arousal, degree to which the harmony impacted the listener's emotions, and listener's preference for the music. There were significant differences between each of the four items upon the level of harmonic progression. When the participants were divided into two groups (i.e., those with a background in music and those with no background in music), there was a significant difference between the groups in terms of emotional potency, but there was no significant interaction effect. This study confirmed that various emotional responses in listeners can be induced by controlling the exogenous variables in musical excerpts. Based on this, it is expected that the harmonic progression level can be provided to the client to be used as an effective therapeutic tool in music therapy intervention.

• Journal of Korea Entertainment Industry Association
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• v.14 no.1
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• pp.61-73
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• 2020

The purpose of this study is to investigate the relationship between educational attainment, history, tourism, psychological benefits, educational benefits, and hedonic benefits on visitors 'intention, and to provide Suwon Hwaseong' We propose a suggestion point. The implications of this study are as follows. First, the participants of Suwon Hwaseong Fortress are not only aware of the fact that the meaning of Mars is simply a stone build-up, but also a place to learn Korean history, experience various cultural experiences and attractions, Should be developed and made available to tourists. Second, the officials of Suwon Hwaseong Fortress should develop educational materials to understand the history of Mars as the representative history of Korean history. Furthermore, contents that show the superiority of Suwon Hwaseong in comparison with various world cultures It is necessary to provide policy support so that it can be developed and provided. Third, the officials of Suwon Hwaseong Fortress will have to worry about the development of culture prototype that can be excavated as a tourism factor when visitors visit and how to provide contents. In order to make sure that tourists do not inconvenience during sightseeing, It should be enough. Finally, the officials of Suwon Hwaseong should provide various entertainment factors around Hwaseong, and should try to create a desire to visit Hwaseong through a systematic PR method.

• Journal of Korea Entertainment Industry Association
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• v.14 no.1
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• pp.167-177
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• 2020

This study purposes to analyze the changes of the pain care awareness and health related quality of life of the people with the chronic low back pain through the participation in the kinesio-taping self application education program. A total of 30 people with chronic LBP participated and they divided into experimental(n=15) and control group(n=15). An experimental group participated in the Kinesio-taping education program for 4 weeks and a control group was treated by a therapist. Through these, the pain care awareness and health related quality of life were analyzed. In the care of the health care awareness, the canadian Occupational Performance Measure was used to assess the subjects' performance and satisfaction. The short form-8 health survey was used to the health related quality of life. The results of the health care awareness and health related quality of life were increased in the experimental group and the statistically significant difference showed between group. This education program is a meaningful method to improve the health related quality of life from the pain care in the daily life by itself. Thus, the kinesio-taping self application education program should be considered for the people with the chronic low back pain.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.375-382
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• 2020

The purpose of this study was to examine the awareness and performance of hand washing in some health-related college students and to provide basic data on the management of hand washing through the difference and correlation between awareness and performance. This study collected data from 367 questionnaires excluding non-response and unfaithful responses from health-related college students in nursing, physiotherapy and occupational therapy. The survey tool was a Likert 5-point scale self-filled questionnaire that examined general characteristics, hand washing awareness and performance. The general characteristics of the subjects were calculated by frequency analysis, and one-way ANOVA, awareness and performance were analyzed by Pearson's correlation. There was a significant difference in the awareness of hand washing in some health-related college students in the presence or absence of infection education and in all areas except gender. According to the characteristics of the health department, the awareness and performance of hand washing showed a significant difference in the order of physical therapy, occupational therapy, and nursing. There was a significant difference in hand washing awareness in grade characteristics and no significant difference in performance. There was a high correlation between awareness and performance of hand washing.