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In this paper, we propose to solve the problem of increasing system memory usage due to an increase in the number of mapping information management when using a NAND flash memory-based storage device in an existing sector-based file system. The proposed technique is to store only mapping information in page units based on index blocks and manage them in block units. To this end, the proposed technique uses a sequential offset for storing and managing a plurality of mapping information in one page in a small block, and a reverse offset for a spare page corresponding to a change in mapping information in the block. Through this, the proposed technique has the advantage that the number of block-unit deletions is less than that of the existing technique, and the system memory usage required for mapping information management is low. Reduced by about 32%.

In this study, we propose an improvement method that can create U-Net model which detect fine concrete cracks by applying a weighted loss function. Because cracks in concrete are a factor that threatens safety, it is important to periodically check the condition and take prompt initial measures. However, currently, the visual inspection is mainly used in which the inspector directly inspects and evaluates with naked eyes. This has limitations not only in terms of accuracy, but also in terms of cost, time and safety. Accordingly, technologies using deep learning is being researched so that minute cracks generated in concrete structures can be detected quickly and accurately. As a result of attempting crack detection using U-Net in this study, it was confirmed that it could not detect minute cracks. Accordingly, as a result of verifying the performance of the model trained by applying the suggested weighted loss function, a highly reliable value (Accuracy) of 99% or higher and a harmonic average (F1_Score) of 89% to 92% was derived. The performance of the learning improvement plan was verified through the results of accurately and clearly detecting cracks.

In this paper, we proposes a method to automatically construct SHACL schemas for RDF knowledge graphs(KGs) generated by Direct Mapping(DM). DM and SHACL are all W3C recommendations. DM consists of rules to transform the data in an RDB into an RDF graph. SHACL is a language to describe and validate the structure of RDF graphs. The proposed method automatically translates the integrity constraints as well as the structure information in an RDB schema into SHACL. Thus, our SHACL schemas are able to check integrity instead of RDBMSs. This is a consideration to assure database consistency even when RDBs are served as virtual RDF KGs. We tested our results on 24 DM test cases, published by W3C. It was shown that they are effective in describing and validating RDF KGs.

In this study, we propose a crack detection method using limited data with a U-Net based image inpainting technique that is a modified unsupervised anomaly detection method. Concrete cracking occurs due to a variety of causes and is a factor that can cause serious damage to the structure in the long term. In general, crack investigation uses an inspector’s visual inspection on the concrete surfaces, which is less objective in judgment and has a high possibility of human error. Therefore, a method with objective and accurate image analysis processing is required. In recent years, the methods using deep learning have been studied to detect cracks quickly and accurately. However, when the amount of crack data on the building or infrastructure to be inspected is small, existing crack detection models using it often show a limited performance. Therefore, in this study, an unsupervised anomaly detection method was used to augment the data on the object to be inspected, and as a result of learning using the data, we confirmed the performance of 98.78% of accuracy and 82.67% of harmonic average (F1_Score).

In this paper, we propose to study the factors affecting the user's intention to use smart music platform, and on the basis of studying the impact of service quality on the user's intention to use, such as perceived usability, perceived ease, perceived entertainment and perceived cost, respectively. Based on this, the impact factors model on the usage intention of smart music platform users was presented, and 398 questionnaires were collected through a survey of university students majoring in Chinese music, and the collected data were obtained by conducting frequency analysis, reliability analysis, exploratory factor analysis, correlation analysis, and structural equation model analysis using spss20.0 and amos20.0. The results show that: Quality of service has a positive effect on perceived usefulness, perceived ease of use, perceived entertainment and perceived cost. A study found that perceived usefulness, perceived ease of use, and perceived entertainment have a positive effect on users' intention of use and perceived cost has a negative effect on their intention of use. Through this conclusion, the entrepreneur presented an important meaning in promoting sustainable development of smart music platforms by improving the operation and profit model of smart music platforms.

The DDS discovery is a behind-the-scenes way in which DDS objects on different nodes find out each other in a same domain. If the DDS discovery takes a long time, the preparation time for DDS communication is also delayed. And if the DDS discovery between several nodes fails, DDS communication between nodes related to them would be also failed. This problems can be a big cause of overall system performance degradation. Therefore, the improvement of performance for the DDS discovery gives the effect that improves the performance of the entire system. In this paper, I propose an efficient new method which improves the performance and reduces the time of DDS discovery. I simulate both the origin and the new proposed method for DDS discovery, and I compare the result of performance. This result will help for improving a DDS discovery in a large-scale system.

With the development of wearable devices, individuals' health status can be checked in real time and risks can be predicted. For example, an application has been developed to detect an emergency situation of a patient with heart disease and contact a guardian through analysis of health data such as heart rate and electrocardiogram. However, health data is seriously damaging when it is leaked as it relates to life. Therefore, a method to protect personal information is essential in collecting health data, and this study proposes a method of collecting data while protecting the personal information of the data owner through a LDP(Local Differential Privacy). The previous study introduced a technique of transmitting feature point data rather than all data to a data collector as an algorithm for searching for fixed  feature points. Next, this study will explain how to improve the performance by up to 75% using an algorithm that finds the optimal number of feature points .

Although various information and communication technologies occupy a place in daily life in the face of the fourth industrial revolution, the contents related to information security in elementary and secondary education courses are mainly related to personal information protection, and the contents and countermeasures of rapidly changing security threats are low in textbooks, and they are far behind the changes. To improve this, this paper suggests that education contents related to information security are included in elementary school real and middle school information textbooks, educational contents related to wireless network and PC security are included to cope with rapidly changing security threats that may arise from the age of the Internet of Things, non-face-to-face classes, and case-based information ethics education can be organized to eradicate curiosity about hacking. Through this paper, we will help prevent information security accidents by establishing basic security measures on our own and strengthening security awareness in the information age.

In this paper, we propose a technique for blockchain service replication and recovery using kubernetes(BR2K) that robustly executes blockchain services based on replication and supports systematic recovery in case of the service failure. Blockchain services are being developed and applied in various fields such as administration, finance, and medical systems based on the features of blockchain, such as decentralization, high security, and data integrity. In such areas where service continuity is important, it is necessary to provide robustness for execution of blockchain services, and a recovery plan for service failure is also required. To this end, BR2K provides an execution replication technique that systematically supports the sustainable execution of blockchain application services. Also, it introduces a robust container registry based on the blockchain service registry, systematically supporting the recovery of service failures by using it. In addition, Truffle, a blockchain service development framework, is extended to utilize the Kubernetes container management tool, and BR2K provides a technique for rapidly deploying blockchain services using the extended framwork.

Social reviews such as SNS feeds and blog articles have been widely used to extract keywords reflecting opinions and complaints from users’ perspective, and often include proper nouns or new words reflecting recent trends. In general, these words are not included in a dictionary, so conventional morphological analyzers may not detect and extract those words from the reviews properly. In addition, due to their high processing time, it is inadequate to provide analysis results in a timely manner. This paper presents a method for efficient keyword extraction from social reviews based on the notion of cohesion scoring. Cohesion scores can be calculated based on word frequencies, so keyword extraction can be performed without a dictionary when using it. On the other hand, their accuracy can be degraded when input data with poor spacing is given. Regarding this, an algorithm is presented which improves the existing cohesion scoring mechanism using the structure of a word tree. Our experiment results show that it took only 0.008 seconds to extract keywords from 1,000 reviews in the proposed method while resulting in 15.5% error ratio which is better than the existing morphological analyzers.

This study was conducted to identify differences in Practical Performance of Nurse between Comprehensive Nursing Care Service Ward and General Service Ward. The subjects of this study were 185 nurses from S hospital, Comprehensive Nursing Care service operating hospital, located in D city. This study used the measuring tool “Nursing Professionalism Scale” developed by Yoon etc(2005) and “Practical Performance Scale” developed by Lee etc(2005). The collected data were analyzed by descriptive statistics, t-test, ANOVA, Duncan test, Pearson’s correlation coefficients and multiple regression using SPSS 20.0 version. As a result of the study, Comprehensive Nursing Care Service Ward nurses have higher Nursing Professionalism than General Service Ward nurses. Also, Nursing Professionalism has an effect on improvement of Practical Performance on Both ward nurses. Therefore, the study can be applied to improve the Practical Performance of the nurses through the establishment of the Nursing Professionalism.

The purpose of this study was to development a uniform shirt for high school boys aged 16-18 in the 7th Human Dimension Survey data of Size Korea. The upper body was analyzed to classify the upper body shape and to understand the characteristics of the body by type. Through this, we wanted to obtain the basic data necessary for the development of school uniform shirts. For data analysis, SPSS Ver. 26.0 program was used. In high school boys, there was no significant difference in height by age, but in width, thickness, length, circumference, shoulder slope, and weight, there were significant differences by age. The upper body types were categorized into four types: long shoulder skinny type, long upper body obese type, short shoulder normal type, and long shoulder normal type. Based on the size and body type data extracted from this study, it is thought that the development of uniform shirts with excellent fit should be realized through practical fashion development and construction of a size system.

In this paper, we propose to evaluate the potential anti-inflammatory properties of root bark extract of Cudrania (C.) tricuspidata on lipopolysaccharide (LPS)-induced inflammation in macrophages of apolipoprotein E (ApoE) knockout (ApoE -/- ) mice, murine model of atherosclerosis. Atherosclerosis is a chronic vascular inflammatory disease. C. tricuspidata is a small tree of the Moraceae family and its extract has anti-inflammatory activities. However, its role in the progress of atherosclerosis is not yet clear. To determine anti-inflammatory effects of C. tricuspidata in atherogenesis, we applied LPS in peritoneal macrophages of ApoE -/- mice and measured cell viability by CCK-8 and expression of pro-inflammatory cytokines by qRT-PCR following treatment with root bark extract of C. tricuspidata. Research data was expressed as differences between the cells treated with LPS and root bark extract and the cells treated with LPS alone (control) by a two-tailed non-parametric Mann–Whitney U-test using GraphPad Instat program. No cytotoxic effect was observed when the cells were treated with the extract at concentrations ≤ 100 ㎍/mL. The expression of inflammatory cytokines, including MCP-1, IL-1β, IFN-γ, TNF-α, and IL-6 were inhibited by the extract. These results indicated that the extract has an anti-inflammatory effect and therefore a possible role in the treatment of atherosclerosis.

In this paper, we design 4-layer TCP/IP that utilizes minimal memory and processor resources in Internet of Things(IoT) systems. The TCP/IP designed in this paper has the following characteristics. First, memory resource is minimized by using minimal memory allocation. Second, processor resource is minimized by using minimal memory copy. Third, the execution time of the TCP/IP can be completed in a deterministic time. Fourth, there is no memory leak problem. The standard in minimal resources for memory and processor derived in this paper can be used to check whether the network subsystems of the already implemented IoT systems are efficiently implemented. As the result of measuring the amount of memory allocation and copy of the network subsystem of Zephyr, an open source IoT kernel recently released by the Linux Foundation, we found that it was bigger than the standard in minimal resources derived in this paper. The network subsystem of Zephyr was improved according to the design proposed in this paper, confirming that the amount of memory allocation and copy were decreased by about 39% and 67%, respectively, and the execution time was also reduced by about 28%.

In this paper, we propose to analyze the impact of perceived over qualification on boundary spanning behavior and job performance. A total of 373 questionnaires were collected from corporate researchers developing VR technology in China to achieve the purpose of this study. The data collected through the survey were analyzed with frequency analysis, reliability analysis, positive factor analysis, structural equation model, etc. using statistical programs SPSS V.22 and AMOS V. 22. The empirical analysis of this study confirms the following findings. First, perceived over qualification is a positive influence on job performance. Second, perceived over qualification to have a positive influence on boundary spanning behavior. Third, boundary spanning behavior is to have a positive effect on job performance. Through the concluding and discussion sections, in-depth discussions on the theoretical implications, practical implications and limitations of the research and its future direction were presented.

The purpose of this study was to investigate the relationship between self-esteem, quality of life, and depression of nursing students, and to determine the effect on depression. The subjects of the study were 311 nursing students and collected data from November 20 to December 5, 2017. Data analysis was performed using the SPSS 21.0 program, t-test, ANOVA, Pearson correlation and multiple linear regression analysis. As a result, there were significant differences in college life satisfaction among general characteristics. Self-esteem was 3.37, quality of life was 3.54, and depression was 16.52. Depression was found to have a significant negative correlation with quality of life. The most significant influence on depression was quality of life, and the explanatory power was 48.2%. Based on the results of this study, it is necessary to develop and apply intervention programs to prevent depression of nursing students.

In this paper, we propose the basic data for cancer patient management by secondary analysis of data from the National Health and Nutrition Survey(KNHANES) to identify factors related to suicidal thinking of cancer patients over 19 years of age in Korean adults lapse of time. The data were analyzed using the IBM SPSS WIN 22.0 program in order to analyze the demographic, health, and mental characteristics of the subjects in 2009 and 2017. It was analyzed using logistic regression analysis. As a result of the study, the factors related to suicidal thinking in cancer patients were activity restriction and experience of depression in 2009(Negelkerke R 2 =.384), and age, marital status, activity restriction, and experience of depression in 2017(Negelkerke R 2=.525). This study is meaningful in that the factors related to suicidal thoughts in cancer patients were identified according to the lapse of time, and the changes in the related factors were confirmed. Development and application of an intervention program to prevent suicide in cancer patients are necessary.

The purpose of this study is to confirm the general characteristics of 119 paramedics who are treating early emergency patients and to confirm the relationship between job stress and job satisfaction and to examine the effect of stress on satisfaction, a questionnaire survey was conducted on 365 paramedics in four Chungcheong provinces. The reliability of the job stress tool was Cronbach α = .87. The job satisfaction tool was Cronbach α = .84. The collected data were analyzed by SPSS WIN 18.0 program. There were differences among the sub - variables of general characteristics, but the general characteristics excluding academic ability were less correlated with job stress, and job satisfaction was higher when the subjects' age, number of dispatches and field hours were smaller. Job stress was found to be low when stress was high on first aid, dispatch, transport, medical guidance, conflicts and emergencies excluding partners. To reduce job stress of 119 paramedics, it is recommended to provide institutional support and education to improve the ability to recruit new emergency personnel and to provide emergency medical care and guidance because of diversification of dispatch methods and appropriate stress management.

The purpose of this study is to identify the effects of stress and sleep quality on depression during clinical practice of nursing students. The subjects of the study were third and fourth graders who experienced clinical practice for more than a semester among nursing students at C University in one region. A total of 107 people were analyzed. Most of the nursing students experienced more than moderate stress and depression during clinical practice, and the quality of sleep was low. During clinical practice, the stress of nursing students showed a weak correlation with the quality of sleep(r=.393, p<.001), and depression showed a strong net correlation with stress(r=.588, p<.001), the quality of sleep(r=.591, p<.001). Factors affecting depression during clinical practice were stress and the quality of sleep. Therefore, effective management methods that can relieve the stress of nursing college students during clinical practice and improve the quality of sleep and active nursing strategies that can prevent depression should be sought.

According to the ‘low self-esteem hypothesis’, low self-esteem plays a causal role in aggression among adolescents, whereas ‘threatened egotism theory’ postulates that aggression is related to a highly favorable view of the self. The primary purpose of the present study was to investigate the effect of self-esteem on aggression among adolescents. Based on the theoretical background, a research model was constructed. The present study analyzed the 5th and 6th wave data from Korea Children and Youth Panel Study (KCYPS). The results showed that self-esteem had a significant negative effect on aggression among high school students. Finally, research implications which contribute to enhancing self-esteem as well as decreasing aggression were also discussed.

This article proposes the unified an arm’s length price of transfer pricing for thin capitalization since the scope of permanent establishment has been enlarged under Digital Economy and the implementation of Blackchain system to resolve the drawback of finding an arm’s length price. The rule of current thin capitalization runs against the non-discrimination of taxation of the tax treaties and the national treatment which deals fairly with goods, sercice and capital money within the country under the treaty of commerce and navigator. In addition, the information of comparable uncontrolled debt are not available of current system to prove the debt which is not subject to the rule of thin capitalization. The united an arm’s length price of transfer pricing for thin capitalization can apply to foreign investment as well as domestic corporations, thereby resolving the problem of the non-discrimination of taxation of the tax treaties and the treaty of commerce and navigation. The availability of transaction level data through Blockchain platform to decide whether the debt can be subject to thin capitalization can resolve the issue of comparable uncontrolled debt transaction which can’t be found in current business transactions. This article should shed light on the proposing of the unified an arm’s length price of transfer pricing for thin capitalization and Blockchain system to prevent the income shifting. This propose provide implication for policymakers on current system of thin capitalization and arm’s length principles.

This study is to evaluate the effectiveness of problem-solving ability by applying a team-based learning model to the classes of humanities and social science students, and to conduct a structural model analysis on the relationship between sub-factors. Team-based learning was conducted six times in six teams with 30 students in the second and third grades of the humanities and social sciences. The problem solving ability score of the target students was significantly higher after team-based learning and was statistically significant. There was no problem in normality with the latent variables, which are the sub-factors of problem solving ability, and the factor load value was statistically significant at the .001 level in the confirmatory factor analysis of the observed variables for the latent variables, which was a valid model. A good level of fitness was also shown in the verification of the fitness of the research model. As a result, it was analyzed that latent variables of cause analysis, problem clarification, planning execution, performance evaluation, and alternative development had an indirect or direct influence on each other.

The purpose of this study is to define how middle school students’ motivation of participation in Judo as a recreational sport activity influences their exercise flow and psychological happiness. To achieve that, this researcher conducted a questionnaire survey with middle school students who participated in 2020 National Amateur Judo Event held in Donghae-si, Gangwon-do from Jan. 18 to 20, 2020, for three days. Of the collected questionnaire copies, the questionnaire copies with insincere or insufficient answers were excluded, and 253 copies were used for data analysis. The results of the study are presented as follows: Firstly, middle school students’ participation motivation in Judo as a recreational sport activity positively influenced their exercise flow. Secondly, participation motivation in Judo as recreational sport activity positively affected psychological happiness. Thirdly, middle school students’ exercise flow to Judo as a recreational sport activity positively influenced their psychological happiness. Therefore, instructors for the recreational sport activity need to develop detailed methods or programs to improve students’ personality and leadership beyond Judo skills in order to achieve positive and smooth communication with participants.

The purpose of this study is to conduct body shape management on women for a certain period of time to determine the structural relationship between the latent variables of life habits, social support, and life satisfaction and the impact on the quality of life. Body shape management was performed with chiropractic adjustments and myofascial relaxation therapy, and a physical therapist with 25 years of experience was used as an expert. The subject of the study was a sample of women in their 20s to 60s residing in Gwangju Metropolitan City, and women who participated in body shape management procedures more than 20 times for the study were asked to fill out a questionnaire using a self-evaluation writing method. The final analysis target was 100 people who made it reasonable to analyze the data. As a result of the study, it was found that the quality of life of women related to health can vary depending on the presence and degree of body shape management. In addition, the degree of life satisfaction varies according to the level of lifestyle and social support, and the direct, indirect, and total effects of the latent variables related to the quality of life were all significant. In this study, the usual body shape management that can improve the quality of life of women gives meaning to the opportunity for women to have desirable lifestyle and to give them a recognition that values quality of life.

Elevators, an important vertical means of transportation used daily, have enriched the city into a state-of-the-art giant skyscraper forest. The purpose of this study is to analyze problems about elevator safety and present engineering and legal improvement measures. The research method adopted the important engineering elements that make up elevator safety and the elevator safety law and the method of analyzing the papers already studied. Based on his experience as a policy advisor to the Korea Elevator Safety Authority, he analyzed the problems of the related statutes, focusing on the construction, electrical, electronic, information and communication, and the elevator safety law, which comprise the elevator safety system. As a result of the research, it was suggested that the so-called legal engineering system should be established through the convergence of laws and disciplines related to elevator safety. This study is expected to be an alternative to establishing an engineering and legal convergence system for elevator safety in the future.

Countries around the world have already taken direct and indirect measures to warn of the harmful effects of mobile phone electromagnetic waves. On the other hand, in the Republic of Korea the installation of Wi-Fi has been expandedwithout restrictions by location, and there is a widespread atmosphere of protesting human rights violations even if young students cannot use mobile phones, ignoring problems caused by the use of mobile phones. Human brain cells are increasingly exposed to electromagnetic waves of mobile phones as the penetration rate of smartphones grows.In order to solve the long-lasting question of whether electromagnetic waves from mobile phones will harm the human body, many studies are being conducted in various countries around the world, andthe recently published findingshave warned of the potential for harm. The labeling of electromagnetic waves alone is not sufficient to raise awareness about the dangers of electromagnetic waves. It is necessary that the Republic of Korea organize and operate a national electromagnetic wave research center in line with its status as an IT powerhouse, along with the revision of the Radio Wave Act, which directly warns the public about the hazards of mobile phone electromagnetic waves and can directly impose obligations on the mobile phone industry.

In this study, to investigate the relationship between early morning delivery's logistics service quality (order quality, delivery quality, and after service quality) and customer satisfaction, and the moderating effect of eco-friendly attitude, the constructs were made up based on previous studies. A survey was conducted on early morning delivery users, and 210 questionnaires were used for empirical analysis. The collected data was analyzed by SPSS 25.0 and AMOS 21.0. The results are as follows: first, it was found that the logistics service quality has a positive effect on customer satisfaction. Second, it was found that the delivery quality has the greatest effect on customer satisfaction. Third, as a result of testing the moderating effect of eco friendly attitudes in the relationship between the logistics service quality and customer satisfaction, in the case of the order quality among the logistics service quality, the differences between the groups were identified according to eco-friendly attitudes. In conclusion, the implications and limitations of this study are presented.

Medical tourism refers to visiting overseas to receive medical services and tourism at the same time. In other words, it can be said that it is a tourism activity that combines medical service, various cultural activities, leisure, and shopping. As such, medical tourism is not limited to simple medical services, but is a new high-value-added industry that creates new profits by fusion with tourism services. Many countries are making continuous efforts to foster their own tourism industry by attracting foreign tourists. Therefore, in order to secure competitiveness in dental services among the medical tourism industry in Korea, this study was to examine the relationship between dentist's treatment, hospital facilities, dental staff, and patient satisfaction. As a result, it was found that the dentist's treatment had a positive effect on both the staff of the dental facility in the hospital and the satisfaction of the patient.

In this paper, I propose an efficient brand identity strategy by topic modeling the Instagram posts, one of SNS(Social Network Service) having more than 1billion world-wide and 500 million daily users. Since the 92% age groups of the Instagram is 18~50 years old (59% 18~29y and 33% 30~49), I set research analysis target three mobile commerce sites to dress and cosmetics sales sites that sale apparels cosmetics and gadgets that recently opened and have operated marketing on diverse channel including SNS. By topic modeling SNS posts for 6 months after launching the site that tagged each m-commerce site brand name or company name, I validate companies’ brand identity strategy works effectively and suggest moderation of strategy for brand image. As a result, I found one of three mobile commerce site has different brand image by users and need different identity set up.

In this paper, we propose an effective software education model for youths with disability. This software education model consists of a four-step process. In the first step, it draws the education curriculum of the software education for different types of disabled youths based on the results of comparative analysis of software education field in special education curriculum. In the second step, it suggests achievement standards for effective software education for the disabled students by classifying students with intellectual disabilities and visual, hearing, and physical disabilities without any multiple disabilities. In the third step, the study developed a modular textbook comprised of unplugged activities using coding robot Albert, physical computing, and block/text coding with the reflection of the characteristic of each type of disability. In the fourth step, it applied the textbook to the school field and educated disabled students focusing on experience to allow them to think logically and by stages about different problems they face in daily lives. In addition, by analyzing the results of youths' performance evaluation and surveys, it was shown that 82.3% of developmental disabilities, 78.8% of visual impairments, 90.9% of hearing impairments, and 78.8% of physically disabilities achieved achievements above the “medium” level. These results prove that the software education model for youths with disabilities proposed in this paper is very effective in improving computational chinking of youths with disabilities.

In this paper, we propose an efficient dynamic workload balancing strategy which improves the performance of high-performance computing system. The key idea of this dynamic workload balancing strategy is to minimize execution time of each job and to maximize the system throughput by effectively using system resource such as CPU, memory. Also, this strategy dynamically allocates job by considering demanded memory size of executing job and workload status of each node. If an overload node occurs due to allocated job, the proposed scheme migrates job, executing in overload nodes, to another free nodes and reduces the waiting time and execution time of job by balancing workload of each node. Through simulation, we show that the proposed dynamic workload balancing strategy based on CPU, memory improves the performance of high-performance computing system compared to previous strategies.