• Journal of Ocean Engineering and Technology
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• v.34 no.3
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• pp.167-179
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• 2020

Recently, the increasing importance of artificial intelligence (AI) technology has led to its increased use in various fields in the shipbuilding and marine industries. For example, typical scenarios for AI include production management, analyses of ships on a voyage, and motion prediction. Therefore, this study was conducted to predict a response amplitude operator (RAO) through AI technology. It used a neural network based on one of the types of AI methods. The data used in the neural network consisted of the properties of the vessel and RAO values, based on simulating the in-house code. The learning model consisted of an input layer, hidden layer, and output layer. The input layer comprised eight neurons, the hidden layer comprised the variables, and the output layer comprised 20 neurons. The RAO predicted with the neural network and an RAO created with the in-house code were compared. The accuracy was assessed and reviewed based on the root mean square error (RMSE), standard deviation (SD), random number change, correlation coefficient, and scatter plot. Finally, the optimal model was selected, and the conclusion was drawn. The ultimate goals of this study were to reduce the difficulty in the modeling work required to obtain the RAO, to reduce the difficulty in using commercial tools, and to enable an assessment of the stability of medium/small vessels in waves.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.34 no.4
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• pp.204-214
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• 2023

Digital therapy using extended reality (XR) holds great promise for addressing the mental health needs of adolescents and young adults. This study addresses a notable research gap in South Korea by systematically reviewing XR-based digital therapy for the mental health of South Korean adolescents and young adults. We analyzed 26 studies encompassing various aspects, including study type, publication date, research field, research methodology, data sources, program types, program content, sample characteristics, target population, assessment tools, and program effectiveness. Notably, 46.15% of the studies employed an experimental design, whereas over 53% utilized non-experimental approaches. Experimental studies lacked a genuine design, standardized questionnaires, and control variables. Similarly, non-experimental studies failed to report specific literature selection criteria. Consequently, future studies should adopt rigorous methodologies to enhance reliability and validity. Moreover, over 85% of the 26 studies focused solely on virtual reality and did not incorporate augmented or mixed reality. This study identifies the limitations of the previous research. These findings emphasize the need for structured investigations to advance the development of XR-based digital therapy to promote mental health in adolescents and young adults in South Korea.

• Journal of Environmental Science International
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• v.16 no.12
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• pp.1451-1462
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• 2007

Heavy metal concentrations in the soil were investigated for the abandoned Samkwang metal mine, Cheongyang-Gun, Chungnam Province, Korea. The concentrations of heavy metal(As, Cd, Cu, Ni, Pb, Zn) were determined in mine soils collected at the abandoned mine sites to obtain a general classification and specification of the pollution in this highly polluted region. The results estimated with the normal test and basis statistic on the central tendency and variation showed that the distribution of heavy metal concentration had significantly different at the range of all locations. The range of spatial distribution on the relationship of heavy metal concentration and pH was $4.8{\sim}8.8$ and heavy metal concentration on the type of land use was highest in forest land, and also Ni and Zn in farm and rice field showed the high concentration. The distribution of heavy metal concentration on the depth of a soil showed that the metal concentrations in subsoil were higher than of those in surface soil, while the concentration of Cu and Ni had no significant difference on the depth of soil. Results from the correlation analysis using the data except the extreme and unusual data revel that Zn-Cd(r=0.867), Zn-As(r=0.797), Zn-Pb(r=0.764), Cu-Cd(r=0.673), Cu-As(r=0.614) and Zn-Ni(r=0.605) were the most important parameters in assessing variations of heavy metal in soil. To discriminate pattern differences and similarities among samples, principal factor analysis(PFA) and cluster analysis(CF) were performed using a correlation matrix. This study suggests that PFA and CF techniques are useful tools for identification of important heavy metal and parameters. This study presents the necessity and usefulness of multivariate statistical assessment of complex databases in order to get better information about the quality of soil and gives the basis information to clean up the abandoned mine sites.

• International Journal of Computer Science & Network Security
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• v.22 no.2
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• pp.91-100
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• 2022

To support early intervention, it is necessary to develop programming system tools that enable accurate, valid, and reliable assessments and can help achieve reasonable, generalizable, and measurable goals. This study examined the Assessment, Evaluation, and Programming System (AEPS) used by associations of children with disabilities in Saudi Arabia to assess its suitability for children with intellectual disabilities. A group of 16 specialists with different professional backgrounds (including special education, physiotherapy, occupational therapy, speech therapy and psychology) from 11 associations of children with disabilities took part in semi-structured personal interviews. The study concluded that AEPS is generally suited for use with children with intellectual disabilities. However, its suitability depends on the type and severity of the child's disability. The more severe the disability, the less effective the AEPS is likely to be. On the basis of this finding the researchers formed interdisciplinary teams to organise and integrate the children's learning and assess the benefits of AEPS, including its accuracy and ability to achieve adaptive, cognitive, and social targets, enhance family engagement and learning and develop basic development skills. This study also identified obstacles associated with the use of AEPS. These include the lack of comprehensiveness and accuracy of the goal, lack of precision and non-applicability to large movements and the fact that it cannot be used with all children with intellectual disabilities. In addition, the research showed that non-cooperation within the family is a major obstacle to the implementation of the AEPS. The results of this study have several implications.

• Computers and Concrete
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• v.21 no.4
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• pp.407-417
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• 2018

Concrete which is a composite material is one of the most important construction materials. Compressive strength is a commonly used parameter for the assessment of concrete quality. Accurate prediction of concrete compressive strength is an important issue. In this study, we utilized an experimental procedure for the assessment of concrete quality. Firstly, the concrete mix was prepared according to C 20 type concrete, and slump of fresh concrete was about 20 cm. After the placement of fresh concrete to formworks, compaction was achieved using a vibrating screed. After 28 day period, a total of 100 core samples having 75 mm diameter were extracted. On the core samples pulse velocity determination tests and compressive strength tests were performed. Besides, Windsor probe penetration tests and Schmidt hammer tests were also performed. After setting up the data set, twelve artificial intelligence (AI) models compared for predicting the concrete compressive strength. These models can be divided into three categories (i) Functions (i.e., Linear Regression, Simple Linear Regression, Multilayer Perceptron, Support Vector Regression), (ii) Lazy-Learning Algorithms (i.e., IBk Linear NN Search, KStar, Locally Weighted Learning) (iii) Tree-Based Learning Algorithms (i.e., Decision Stump, Model Trees Regression, Random Forest, Random Tree, Reduced Error Pruning Tree). Four evaluation processes, four validation implements (i.e., 10-fold cross validation, 5-fold cross validation, 10% split sample validation & 20% split sample validation) are used to examine the performance of predictive models. This study shows that machine learning regression techniques are promising tools for predicting compressive strength of concrete.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.4
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• pp.412-422
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• 2009

This study was conducted to assess exposure to musculoskeletal disorder(MSD) risk factors in hospital personnel who performed non-routinized work tasks. A tool ("PATH-KOSHA" version) was newly revised from PATH(Posture, Activity, Tools and Handling) method and uploaded into a personal digital assistant(PDA). The version was used, on a basis of direct-observation, to collect PATH data at the 2 hospital settings in different regions. Job analysis was performed to get various information (e.g., work and rest time, task type) as well. The data collected were visually checked for data cleaning and stored for future data analysis. A total of 1,992 PATH observations were made for 37 hospital workers. Exposure levels varied across 18 items of the MSD risk factors. The highest percent time spent on non-neutral postures was 53% for wrist deviation, followed by 47%(pinch grip), 35%(trunk posture), 23%(neck posture), and 20%(shoulder/arm posture). The highest percent time spent among hand activity level(HAL) variables was 55% for HAL-cat2 (HAL: 3.3 - <6.7). The percent time of items with respect to both loads with more than 5kg and contact stress was less than 4%. Vibration was not exposed in the study workers. Different aspects were discussed for findings. The study results showed that wrist deviation was highest in percent time spent on awkward posture while HAL-cat2 was highest in hand repetition. The study suggests that distal upper extremity posture and HAL should be primarily addressed and controlled in non-routinized work including the hospital settings.

• Journal of Software Assessment and Valuation
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• v.16 no.2
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• pp.1-8
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• 2020

The similarity detection to plagiarism or duplication of computer programs requires a different type of analysis methods and tools according to the programming language used in the implementation and the sort of code to be analyzed. In recent years, the similarity appraisal for the object code in the embedded system, which requires a considerable resource along with a more complicated procedure and advanced skill compared to the source code, is increasing. In this study, we described a method for analyzing the similarity of functional units in the assembly language through the conversion of object code using the reverse engineering approach, such as the reverse assembly technique to the object code. The instruction and operand table for comparing the similarity is generated by using the syntax analysis of the code in assembly language, and a tool for detecting the similarity is designed.

• Journal of the Korean School Mathematics Society
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• v.17 no.3
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• pp.337-358
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• 2014

The purpose of this study is to investigate how storytelling is embodied in the Mathematics I textbooks for first grade high school students in the 2009 revised curriculum and the perception of secondary math teachers and students of those books. Furthermore, in order to have some implications on newly ongoing textbook development, this thesis sets up the following goals for inquiry into the effect on storytelling. First, are there any noticeable differences among the 10 types of mathematics I textbooks for high school first graders in the 2009 revised curriculum? Second, what do teachers and students think of textbooks which apply storytelling techniques? The results are as follows. The frequency of storytelling types that appeared in the textbooks is as follows: real-life connection type and inter-scholarship type take up 47.55% and 24.51% respectively, followed by decision-making type with 10.52%, math history type with 10.17% and tool-using type with 7.05%. Within the contents, math history type showed up on reading material from every textbook. And it is worth considering that real-life-connection type has the most various topics and is mainly for arousing interest and checking up on some concepts. However, inter-scholarship type is usually related to science, and decision-making type is included for error analysis and tool-using type for reading materials about math programs. The results of this study suggest that many of the teachers who participated showed some kind of understanding of storytelling but there were not many who are actually incorporating that into their own classes. It is also essential that we develop textbooks that are effective for storytelling classes, hold regular symposiums as well as teacher training, and create tools for proper assessment. Furthermore, students think that textbooks based on storytelling would have positive effects as long as they are supported by enough time, a sufficient number of classes and tests with validity.

• Child Health Nursing Research
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• v.9 no.2
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• pp.149-161
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• 2003

Purpose: The purpose of this study is to identified patterns and trend of studies and to analyzed the nursing research related to the mother-child interaction in Korea and to improve direction of nursing research in mother-child interaction in Korea. Method: The research studies related to the mother-child interaction were selected from the Korean Nurses Academic Society Journal, and from dissertation, which were conducted between 1961 and 2002 with the consideration of the condition and the cultural specialty of Korea. The total numbers of the studies were 34. These studies were classified according to 1)time of publication or presentation, 2)research design, 3)type of interaction objects, 4)measurement tool, and 5)chief content of studies. Ressult: 1) Until 1984, there was no research studies related to mother-child interaction. The number of studies on the mother-child interaction on the mother-child interaction has been increased rapidly after 1985. The mother-child interaction studies were 13(38.2％) from the doctoral dissertation, 4(11.8％) from the Master's theses and 17(50％) other papers were published in academic journals. 2) Experimental studies of research design was used in these research studies was 13(38.2％). Descriptive studies was 8(23.6％), correlational studies was 4(11.8％) and comparative studies was 4(11.8％). Qualitative study was just one(2.9％) and literature review was 4(11.8％). Especially experimental studies has been increased. 3) Participants of these studies were mother and infant 29(85.5％), father and infant 2(5.9％), mother and fetus 2(5.9％) and nurse and infant 1(2.9％) 4) Utilization of instruments as follows: 13 studies used Walker et al(1986)'s MIPIS (Mother-Infant Play Interaction Scale), 6 studies used Barnard(1978)'s NCAFS (Nursing Child Assessment Feeding Scale), 4 studies used NCATS(Nursing child Assessment Teaching Scale) for assessing mother-infant interaction. 3 studies used Stainton(1981)'s Parent-Infant Interaction Scale. Choi(1987), Kim(1999) and Kim and Son(1997) used measurement tool researcher made which was modified from NCATS (Nursing child Assessment Teaching Scale) and AMIS(Assessment of Mother-Infant Sensitivity Scale). Other tools used to survey influencing factors of interaction. 5) Content of the research studies were classified 3 different types, such as ① studies about the mother-child interactions' pattern, ② studies about influencing factors of the mother-child interaction, ③ studies about effect of nursing intervention program to improve the mother-child interaction. Conclusion: Therefore we make following suggestions which are made based on the above research analysis : 1) In the future research studies need to compare with other area of discipline in mother-child interaction. 2) More attention and in depth research is needed to validate in terms of research design and statistical data analysis. 3) It is important to develop the instruments which is culturally acceptable in Korea society. 4) The results of correlational studies and experimental studies needs to the integrated by meta analysis.

• Environmental Mutagens and Carcinogens
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• v.23 no.2
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• pp.56-62
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• 2003

The liver progenitor cells could form a potential target cell population fore both tumor-initiating and -promoting chemicals. Induction of drug-metabolizing and antioxidant enzymes, including AhR-dependent CYP1A1, NQO-1 and AKR1C9, was detected in the rat liver epithelial WB-F344 "stem-like" cells. Additionally, WB-F344 cells express a functional, wild-type form of p53 protein, a biomarker of genotoxic events, and connexin 43, a basic structural unit of gap junctions forming an important type of intercellular communication. In this cellular model, two complementary assays have been established for detection of the modes of action associated with tumor promotion: inhibition of gap junctional intercellular communication (GJIC) and proliferative activity in confluent cells. We found that the PAHs and PCBs, which are AhR agonists, released WB-F344 cells from contact inhibition, increasing both DNA synthesis and cell numbers. Genotoxic effects of some PAHs that lead to apoptosis and cell cycle delay might interfere with the proliferative activity of PAHs. Contrary to that, the nongenotoxic low-molecular-weight PAHs and non-dioxin-like PCB congeners, abundant in the environment, did not significantly affect cell cycle and cell proliferation; however both groups of compounds inhibited GJIC in WB-F344 cells. The release from contact inhibiton by a mechanism that possibly involves the AhR activation, inhibition of GJIC and genotoxic events induced by environmental contaminants are three important modes of action that could play an important role in carcinogenic effects of toxic compounds. The relative potencies to inhibit GJIC, to induce AhR-mediated activity, and to release cells from contact inhibition were determined for a large series of PAHs and PCBs and their metabolites. In vitro bioassays based on detection of events on cellular level (deregulation of GJIC and/or proliferation) or determination of receptor-mediated activities in both ?$stem-like^{\circ}{\times}$ and hepatocyte-like liver cellular models are valuable tools for detection of modes of action of polyaromatic hydrocarbons. They may serve, together with concentration data, as a first step in their risk assessment.