KJC Korea
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In this paper, we propose an efficient disk buffer replacement policy which improves hit ratio and reduces writing operations of flash based storages. The flash based storage has many advantages, including a small form factor, non-volatility and high reliability, but there are problems caused by own limitations, like not-in-place update, short life cycle and asymmetric I/O latencies. To redeem these problems, this paper proposes the write weighted probability of reference(2WPR) policy. 2WPR policy predicts re-referencing probability and calculates localities of each page. Furthermore, by weighting write operations to every pages, 2WPR can reduce write operations to flash based storage. In addition, we can improve the performance with higher hit ratio and reduce the number of write operations and consequently shorten the latencies of each operation. The results show that our policy provides improvements of up to 10% for the hit ratio with the reduction of up to 5% for the flash writing operation compared with other policies.

Modern GPU can execute general purpose computation on the graphic processing unit, and provide high performance by exploiting many core on GPU. To run AES algorithm efficiently, parallel computational resources are required. However, computational resource of CPU architecture are not enough to cryptographic algorithm such as AES whereas GPU architecture has mass parallel computation resources. Therefore, this paper reduce the time to execute AES by employing parallel computational resource on GPGPU. Unfortunately, AES cannot utilize computational resource on GPGPU since it isn’t suitable to GPGPU architecture. In this paper, IPC based dynamic SM management technique are proposed to efficiently execute AES on GPGPU. IPC based dynamic SM management can increase and decrease the number of active SMs by using IPC in run-time. According to simulation results, proposed technique improve the performance by increasing resource utilization compared to baseline GPGPU architecture. The results show that AES improve the performance by 41.2% on average.

The use of NAND flash memory is continuously increased with the demand of mobile data in the IT industry environment. However, the erase operations in flash memory require longer latency and higher power consumption, resulting in the limited lifetime for each cell. Therefore, frequent write/erase operations reduce the performance and the lifetime of the flash memory. In order to solve this problem, management techniques for improving the performance of flash based storage by reducing write and erase operations of flash memory with using disk buffers have been studied. In this paper, we propose a CPWL to minimized the number of write operations. It is a disk buffer management that separates read and write pages according to the characteristics of the buffer memory access patterns. This technique increases the lifespan of the flash memory and decreases an energy consumption by reducing the number of writes by arranging pages according to the characteristics of buffer memory access mode of requested pages.

In this paper, we introduce a technique for generating synthetic benchmarks based on time series data. Many of the data measured on IoT devices have a time series characteristic that measures numerical changes over time. However, there is a problem that it is difficult to model the data measured over a long period as generalized time series data. To solve this problem, this paper introduces the BST-IGT model. The BST-IGT model separates the entire data into sections that can be easily time-series modeled, collects the generated data into templates, and produces new synthetic benchmarks that share or modify characteristics based on them. As a result of making a new benchmark using the proposed modeling method, we could create a benchmark with multiple aspects by mixing the composite benchmark with the statistical features of the existing data and other benchmarks.

In this paper, we derive a common computational part in an algorithm that can simultaneously perform multiplication and square over finite fields, and propose a low-area bit-parallel systolic array that reduces hardware through sequential processing. The proposed systolic array has less space and area-time (AT) complexity than the existing related arrays. In detail, the proposed systolic array saves about 48% and 44% of Choi-Lee and Kim-Kim’s systolic arrays in terms of area complexity, and about 74% and 44% in AT complexity. Therefore, the proposed systolic array is suitable for VLSI implementation and can be applied as a basic component in hardware constrained environment such as IoT.

In this study, we solve an online multi-object problem which finds object states (i.e. locations and sizes) while conserving their identifications in online-provided images and detections. We handle this problem based on a tracking-by-detection approach by linking (or associating) detections between frames. For more accurate online association, we propose novel online appearance learning with discrete fourier transform and partial least square analysis (PLS). We first transform each object image into a Fourier image in order to extract meaningful features on a frequency domain. We then learn PLS subspaces which can discriminate frequency features of different objects. In addition, we incorporate the proposed appearance learning into the recent confidence-based association method, and extensively compare our methods with the state-of-the-art methods on MOT benchmark challenge datasets.

In this paper, we propose a pipe leak detection system through data collection using low-power wireless acoustic sensor modules and data analysis using deep auto-encoder. Based on the Fourier transform, we propose a low-power wireless acoustic sensor module that reduces data traffic by reducing the amount of acoustic sensor data to about 1/800, and we design the system that is robust to noise generated in the audible frequency band using only 20kHz~100kHz frequency signals. In addition, the proposed system is designed using a deep auto-encoder to accurately detect pipe leaks even with a reduced amount of data. Numerical experiments show that the proposed pipe leak detection system has a high accuracy of 99.94% and Type-II error of 0% even in the environment where high frequency band noise is mixed.

In this paper, we proposes to develop an online academic vocabulary dictionary as a way of educating academic vocabulary for content-oriented Korean language education. Various academic languages exist in the content-based Korean language teaching materials they encounter when studying at university. You cannot understand or produce academic text without knowing the academic vocabulary. Therefore, one of the tasks of Korean language education has become to improve educational efficiency by preparing a method for academic vocabulary education that is most suitable for them in consideration of their own. Prior to the development of the online academic vocabulary dictionary, the institute conducted a basic study on how the content should be contained in the online dictionary. Online academic vocabulary dictionaries allow students to naturally link their limited education into and out of the classroom, thereby overcoming the limitations of vocabulary education at the educational scene and maximizing their educational effectiveness.

The definition of educational games, the importance of game development, and the characteristics of educational games are described. The design of the screen used in the game and the algorithm used are described. We explained the game implementation in the system environment and experiment, and the questionnaire showed whether there is nonviolence of the game, games preferred by children, game benefits, and fun elements of the game. The superiority of the game was described by comparing and analyzing the educational shooting game proposed in this paper with the existing game. The existing children's games had many shortcomings in terms of commercial and educational aspects, but the proposed games proved to be less violent and have educational effects.

In this paper, we propose an efficient session management scheme for low-latency communications in 5G systems. The main idea of the proposed scheme is to prevent unnecessary reattempt signalling overhead when the session establishment for low-latency communications fails. Also, this method avoids network resource waste and battery drain of mobile devices. If a UE(User Equipment) fails to establish an Always-on PDU session for low-latency communications with the 5G systems because of network failure or resource unavailability, the proposed method prevents the UE’s re-establishment of the Always-on PDU session by the specific information in the NAS(Non-Stratum) message from the 5G systems. Through simulation, we show that the proposed efficient session management scheme (ESMS) minimizes unnecessary signalling overhead and improves battery efficiency of mobile devices compared to existing legacy mechanism in 5G systems.

The telecare medical information system (TMIS) supports convenient and rapid health-care services. A secure and efficient authentication and key agreement scheme for TMIS provides safeguarding electronic patient records (EPRs) and helps health care workers and medical personnel to rapidly making correct clinical decisions. Giri et al. proposed an RSA-based remote user authentication scheme using smart cards for TMIS and claimed that their scheme could resist various malicious attacks. In this paper, we point out that their scheme is still vulnerable to lost smart card attacks and replay attacks and propose an improved scheme to prevent the shortcomings. As compared with the previous authentication schemes for TMIS, the proposed scheme is more secure and practical.

In this paper, we propose a scheme that minimizes the energy imbalance problem of solar-powered wireless sensor network (SP-WSN) using both a mobile sink capable of wireless power transfer and an efficient clustering scheme (including cluster head election). The proposed scheme charges the cluster head using wireless power transfer from a mobile sink and mitigates the energy hotspot of the nodes nearby the head. SP-WSNs can continuously harvest energy, alleviating the energy constraints of battery-based WSN. However, if a fixed sink is used, the energy imbalance problem, which is energy consumption rate of nodes located near the sink is relatively increased, cannot be solved. Thus, recent research approaches the energy imbalance problem by using a mobile sink in SP-WSN. Meanwhile, with the development of wireless power transmission technology, a mobile sink may play a role of energy charging through wireless power transmission as well as data gathering in a WSN. Simulation results demonstrate that increase the amount of collected data by the sink using the proposed scheme.

In this paper, we propose the terminal authentication system using blockchain and TOTP(Time-based One-time Password Algorithm) to sustain a continuous authentication between user device and service device. And we experiment this system by using door-lock as a terminal of IoT(Internet of Things). In the future, we can apply this result to several devices of IoT for convenience and security. Although IoT devices frequently used everyday require convenience and security at the same time, it is difficult for IoT devices having features of the low-capacity and light-weight to apply the existing authentication technology requiring a high amount of computation. Blockchain technology having security and integrity have been used as a storage platform, but its authentication cannot be performed when the terminal cannot access any network. We show the method to solve this problem using Blockchain and TOPT.

The text ranking algorithm is a representative method for keyword extraction, and its importance is emphasized highly. In this paper, we compare the performance of recent research and experiments with TF-IDF, SMART, INQUERY and CCA algorithms, which are used in text ranking algorithm.. After explaining each algorithm, we compare the performance of each algorithm based on the data collected from news and Twitter. Experimental results show that all of four algorithms can extract specific words from news data equally. However, in the case of Twitter, CCA has the best performance to extract specific words, and INQUERY shows the worst performance. We also analyze the accuracy of the algorithm through six comparison metrics. The experimental results present that CCA shows the best accuracy in the news data. In case of Twitter, TF-IDF and CCA show similar performance and demonstrate good performance.

The IISS(Integrated Interface Storage System) software uses communication methods such as DSS(Data Sharing Service), UDP to perform the function of sending all messages from the Combat Management System to the analytical computer. Because IISS software handles all message used in the Combat Management System, the source code is large and has a highly dependent feature on message changes. Modification of software is a task that requires a lot of labor, such as series of software reliability test. so research has been conducted to reduce software development costs, including minimizing software modifications. In this paper, We study the method of messages receiving and architectural structure improvement to minimize reliance on message changes in the Combat Management System and improve the modifiability. Reduced message dependency by changing the way DSS and UDP protocols are communicated to Packet Sniffing. In addition, Factory Method Pattern were applied to improve the software design. Test comparing existing software and development elements have confirmed that the software has improved its modifiability and reuse.

In this paper, the development of a system to translate definition of English technical terms of IEV into Korean and implementation of a web system of prototype Korean Electropedia are introduced. The work was consisted of 3 parts. The 1st work was building databases for the translation of English definitions of IEV into Korean. The 2nd work was that Korean TC 1 members translated English terms’ definitions into Korean and modified Korean definitions by significance levels, using developed computer programs and the work database. The last work was to make a document for the report of project and to implement a web system of prototype Korean Electropedia. As a result, 20,996 English definitions of electronical terms were translated into Korean and a prototype web system for Korean Electropedia was implemented. In the future, it is needed to open regular Korean Electropedia and link to IEC’s Electropedia.

In this paper, we propose the moderating effects and mediation effects of social support on the relationship between art therapists' job stress and psychological burnout. Based on the previous studies, this study set up four types of variables: 1) independent variable, 2) moderating variable, 3) mediation variable, and 4) dependent variable. Job stress was identified as an independent variable, social support was identified as both a moderating variable and mediation variable, and psychological burnout was identified as a dependent variable. To empirically conduct this study, a total of 200 questionnaires were distributed to art therapists. Consequently, a total of 150 survey responses were collected. The survey results are as follows. First, there were not differences in job stress, psychological burnout, and social support due to personal environmental factors. This included career, employment type and working hours. Second, the result showed a high-level of correlation among job stress, psychological burnout, and social support. Third, social support was found to have a moderating effect on the relationship between the art therapists' job stress and psychological burnout. Forth, social support was found to have a moderating effect on the relationship between the art therapists' job stress and psychological burnout.

In this paper, we propose an analyze the effects of CPR education for kindergarten students, to determine their role as first responders, and to use them as basic data for the development and activation of CPR education programs for future kindergarten students. Five CPR training sessions were repeated for 10 weeks for children aged 6 and 7 years in kindergarten in J city, and objective data was collected using feedback equipment. The data were analyzed by t-test and paired t-test using SPSS 23.0 for win statistics program. The results showed that chest compression depth, chest compression velocity, and chest compression hand position increased significantly after repeated training. In conclusion, the cardiopulmonary resuscitation training for kindergarten students was effective, and the kindergarten students could play the role of first responders.

In this paper, we purpose to describe the relationship and influencing factors among self-esteem, loneliness on subjective well-being of middle-aged women. The subjects were 157 middle-aged women through convenience sampling residing in S city, C and three G provinces. The data were collected from June 15th to July 31st, 2019. The data were analyzed through t-test, ANOVA, Pearson correlation coefficient and multiple regression with SPSS/WIN 22.0. The result showed self-esteem, loneliness on subjective well-being averaged 31.39(out of 40), 35.37(out of 80), 5.03(out of 7). In term of correlations, subjective well-being of middle-aged women was significantly positively correlated with self-esteem (r=.581, p<.001), and significantly negatively related with loneliness (r =-.621, p<.001)). Variables affecting subjective well-being were self-esteem (β=.324 p<.001), loneliness(β=-.424, p<.001). These variables represented 44.5% of the subject's subjective well-being. These results suggest that development of a intervention program is needed to lowers loneliness and increases self-esteem in order to increase the subjective well-being of middle-aged women.

In this paper, we propose a identity the effect of acculturative stress on life satisfaction with the mediating effect of self-esteem among marriage migrant women participating in Korean traditional dance. Participants of this study were marriage migrant women (experimental group: 28, control group: 30). Surveys that were taken before and after the 3 months of participation in Korean traditional dance were analyzed using SPSS 21.0. Results indicated that acculturative stress had a positive influence on self-esteem and life satisfaction, and self-esteem mediated the effect of acculturative stress on life satisfaction among marriage migrant women who participated in Korean traditional dance. Therefore, this study confirmed that acculturative stress had a direct effect on self-esteem and life satisfaction and had an indirect effect on life satisfaction mediated by self-esteem among marriage migrant women who participated in Korean traditional danc

This study was conducted to identify the effects of the degree of death orientation, attitudes toward withdrawing life-sustaining treatment, and awareness of biomedical ethics on paramedic students’ own biomedical ethics. The participants of this study were 228 paramedic students from a college located in D city. Data were collected from April to June 2019 through a self-report questionnaire. There was a positive correlation between awareness of biomedical ethics and attitude toward withdrawing life-sustaining treatment (r=.63, p<.001). Multiple linear regression analysis showed that the factors affecting students’ awareness of biomedical ethics were religion (β=.12, p=.018) and their attitude toward withdrawal of life-sustaining treatment (β=.61, p<.001), with an explanatory power of 41.0%. Educational programs must focus on attitudes toward withdrawing life-sustaining treatment to improve paramedic students’ awareness of biomedical ethics.

In this study, the inlet duct and guide vane of the gas floating absorption tower were redesigned to improve the desulfurization efficiency so that the exhaust gas can be uniformly introduced into the absorption tower. In order to reduce the sulfur oxide pollutants among the main sources of air pollutants in industrial boilers, the existing equipment is redesigned and solved. For this purpose, change the exhaust gas, the slurry and recycling the adsorbent to improve the removal efficiency of SOx component in the exhaust gas inside the gas floating absorption tower so as to uniformly contact. And the initial design value and CFD value for the pressure loss from the boiler outlet to the gas floating absorption tower outlet are verified. Also, the velocity distribution of the exhaust gas, the concentration distribution of the recycled adsorbent, the liquid slurry behavior, and the pressure loss were compared. The results confirmed that the desulfurization efficiency was improved because the pressure loss from the boiler outlet to the absorption tower outlet was reduced and the deflection of the exhaust gas was minimized.

The purpose of study is to identify the perception of image-making regulations change of airline cabin crew and analyze the relationship among the perception of regulations change, occupational choice motives and career decision of female university students majoring in airline service in Kwang-ju and Jeonnam area. The survey was in 203 for a month from November 18 to December 13, 2019. The collected data were analyzed using ‘SPSS statistics 21.0.’ Analytical methods such as frequency analysis, factor analysis, reliability analysis and multiple regression analysis were used. The findings of this study are presented as follows: Students majoring in airline service are positively aware of image-making regulations changes of airline cabin crew, positive perception of regulation changes has a statistically significant impact on occupational choice motives and career decision, and occupational choice motives have an effects on career decision. In conclusion, the study has implications for providing information to airlines to understand the applicants and to students preparing for employment. However, there is a limitation in that the sample of this study is limited to only female university students majoring in airline services in a specific area, and the size of the sample is not large.

The purpose of this study was to investigate the effect of university students' mobile phone Overdependence on their quality of life. To achieve the purpose of the study, a survey was conducted on 348 male and female students attending a four-year college in C city. Data were analyzed using the structural equation model of SPSS 19.0 and AMOS 18.0. As a result, male students showed higher Overdependence on mobile phone than female students, and male students used games, videos, and searches in order. Academic satisfaction showed higher male and female students in all majors, rather than liberal arts, mobile phone excessive Overdependence appeared to affect academic satisfaction. In addition, the overdependence of mobile phone of university students has a significant effect on academic satisfaction, and academic satisfaction has an effect on life satisfaction. In particular, college students entering adulthood remained intact in their adolescence, affecting college life due to mobile phone overdependence.

In this paper, we propose a classification analysis method for diagnosing and predicting problematic smartphone use in order to provide policy data on problematic smartphone use, which is getting worse year after year. Attempts have been made to identify key variables that affect the study. For this purpose, the classification rates of Decision Tree, Random Forest, and Support Vector Machine among machine learning analysis methods, which are artificial intelligence methods, were compared. The data were from 25,465 people who responded to the ‘2018 Problematic Smartphone Use Survey’ provided by the Korea Information Society Agency and analyzed using the R statistical package (ver. 3.6.2). As a result, the three classification techniques showed similar classification rates, and there was no problem of overfitting the model. The classification rate of the Support Vector Machine was the highest among the three classification methods, followed by Decision Tree and Random Forest. The top three variables affecting the classification rate among smartphone use types were Life Service type, Information Seeking type, and Leisure Activity Seeking type.

As the cosmetics beauty industry grows into a key next-generation industry, the establishment of an industrialization center is needed, but failure to verify the adequacy and feasibility of the investment could lead to financial burdens. In this study, the project costs and facilities of an industrial center are reviewed to analyze its economic feasibility based on the cost estimates, revenue estimates, estimated profit or loss calculations, and estimated operating cash flows. The profit estimation criteria were analyzed by applying 90 per cent of expected orders for research projects (24 billion won) and 12 per cent of rental rates for testing equipment (4.5 billion won for construction), and the benefit/cost ratio is higher than 1.02 per cent and the net present value is higher than '0' won, and the internal rate of return is also more than 5.06 per cent for all three analytical methods. Therefore, in order for the construction of a cosmetics beauty industrialization center to be economically feasible, it is necessary to maintain research project orders of more than 90 percent and return on equipment rent of more than 12 percent, and a strategic approach is needed to diversify business profits.

Cryptocurrency, represented by Bitcoin, initially received little public attention, but recently raised global cryptocurrency investments with recognition of future value. The academic interest in cryptocurrency lies elsewhere. This is because the future value of cryptocurrency is likely to be highly applicable to the technology underlying cryptocurrency. The technology is the blockchain. The purpose of this study is to find out what factors influence logistics companies to adopt blockchain technology. Based on the TOE frame, this study presented expected profit, organizational readiness, technology compatibility, and competitive pressure as factors of adoption of blockchain technology. And the effects of these factors on the adoption intention of logistics companies were analyzed empirically. A survey was conducted on Korean logistics companies. Analysis of the collected data showed that expected profit, organizational readiness, technology compatibility, and competitive pressures influence the intention to adopt blockchain technology. Among them, however, expected profit and organizational readiness were found to have the greatest influence on adoption intention.

In this paper, we propose a direction of teaching method for future generations. In order to suggest such the direction, teaching and learning materials that integrate coding activities and mathematical modeling were developed through top-down and bottom-up processes. Coding and engineering experts and mathematics education experts developed teaching and learning materials through councils (top-down courses) and applied them to 24 high school first graders based on student responses (bottom-up courses). Additionally, the developed curriculum helped students increase interest and motivation and realize conceptual understanding, problem posing, and problem solving in mathematics. On the basis of these results, it provided an idea about how to develop curriculum combining mathematical modeling with coding activities, needed for the fourth industrial revolution.