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Vol.11 No.4

초록보기
Abstract

In practice, the most important performance parameters for music information retrieval (MIR) service are robustness of fingerprint in real noise environments and recognition accuracy when the obtained query clips are matched with the an entry in the database. To satisfy these conditions, we proposed a conjoined fingerprint algorithm for use in massive MIR service. The conjoined fingerprint scheme uses interhash and intrahash algorithms to produce a robust fingerprint scheme in real noise environments. Because the interhash and intrahash algorithms are masked in the predominant pitch estimation, a compact fingerprint can be produced through their relationship. Experimental performance comparison results showed that our algorithms were superior to existing algorithms, i.e., the sub-mask and Philips algorithms, in real noise environments.

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Abstract

This study examined whether game usage would alleviate players’ aggressive tendencies. Other game-related variables, psychological care factors (adaptive game use tendency, game self-efficacy, and life self-efficacy), and psychological problem factors (loneliness and depression) were controlled for determination of the effect. We drew on the catharsis theory from therapeutic psychology literature to explain how game usage contributes to the alleviation of aggressive tendencies. Over two weeks data were collected from 918 participants online. The results indicated that gaming activity had a significant effect on aggression. Higher levels of game and life self-efficacy, as well as adaptive game use tendencies, decreased the degree of aggression. Likewise, higher levels of loneliness and depression reduced the degree of aggression. Results and implications are discussed.

Hea-Suk Kim(Seoul Women’s University) pp.15-24 https://doi.org/10.5392/IJoC.2015.11.4.015
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Abstract

The purpose of this study was to investigate the effect of the use of video resources on improving listening comprehension. 86 students enrolled in a summer session at a Korean university participated in the study. They were assigned to one of three groups based on the results of their TOEIC test scores: 29 students were assigned to the low group, 29 students to the intermediate group, and 28 students to the advanced group. Each group studied the same lessons using authentic video materials. They were taught for 10 sessions over three weeks. The pre- and post-test design helped to determine whether authentic videos were effective in improving listening skills for all proficiency levels. In addition, a questionnaire investigated students’ perceptions toward using video resources. Paired sample t-tests, ANOVAs, and an ANCOVA were utilized to identify significant differences. It was concluded that in the intermediate and advanced proficiency groups, the students’ listening skills increased significantly after learning with videos. In addition, listening improvements among the intermediate and advanced students were much greater than those of the low proficiency group. As for students’ perceptions toward using video resources for improving their English listening skills, they responded positively. Based on these findings, pedagogical implications are suggested, and future studies will be discussed.

Sun-Hyung Lee(Hoseo University,) ; Choon-Hee Lim(Kunsan National University,) ; (Oregon State Univ.) pp.25-30 https://doi.org/10.5392/IJoC.2015.11.4.025
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Abstract

The objective of this study is to identify the current state of usage and needs for Smart Technology (ST) in the elderly care facilities based on the point of view of staff members. Using survey via mails, data were analyzed with responses from top- or middle-level staff members working in 171 elderly care facilities located in Seoul, Gyeonggi-do, and Chungcheongnam-do. Results indicated that the most needed smart technology was home automation, followed by nurse call system and health monitoring. The technology with the highest feasibility was health monitoring, followed by nurse call system and video phone. Staff members in higher positions working in the elderly care facilities had the highest expectation in improving the image of their facilities by using ST, while they had low expectation for the fact that ST may increase the locus of control of the elderly. This study implies that ST implementations may vary depending on the level of responsibility of staff members and ST how people responsible for the elderly care facilities subjectively perceive the ST.

Soonjoo Park(Eulji University) ; Jung-wha Choi(Eulji University Hospital) pp.31-37 https://doi.org/10.5392/IJoC.2015.11.4.031
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Abstract

The objectives of this study were: 1) to determine smartphone addiction, visual display terminal syndrome (VDTS) related symptoms, and state anxiety among adolescents, and 2) to identify the relationship among these variables. Data were collected via selfadministrated questionnaire survey from May to June, 2013. The survey was carried out with 540 voluntary participants at 13 to 24 years old from middle schools, high schools, and universities in Korea. The presence and severity of smartphone addiction, VDTS symptoms, and state anxiety were measured using Korean Smartphone Addiction Proneness Scale, VDTS Questionnaire, and State Anxiety Inventory, respectively. Data were analyzed by Cohen’s Kappa coefficient, Kruskal-Wallis test, and Mann-Whitney U test. The mean score of smartphone addiction for all students was 2.17 ± 0.51. The mean scores of smartphone addiction depending on school grade were 2.12 ± 0.53, 2.03 ± 0.48, and 2.42 ± 0.43 for middle school, high school, and college students, respectively. Subjects who experienced minor level of VDTS symptoms had a score of 0.49 ± 0.49 for VDTS symptoms. The score was increased when the level of addiction was higher. There were significant differences in VDTS subjective symptoms among smartphone addiction groups (p<.001). High-risk group of smartphone addiction had the highest scores in every subdomain of VDTS symptoms. Differences were also found in state anxiety among the three groups with smartphone addiction. The findings of this study showed that approximately one out of three adolescents might be classified into problematic smartphone users. Therefore, it is important to educate problematic smartphone users about smartphone addiction and VDTS symptoms to prevent further addiction and aggravation of anxiety.

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Abstract

Non-orthogonal multiple access (NOMA) where all users share the entire time and frequency resource has paid attention as one of the key technologies to enhance the spectral efficiency and the total throughput. Nevertheless, as the number of users and SIC error increase, the inter-user interference and the residual interference due to the SIC error also increase, resulting in performance degradation. In order to mitigate the performance degradation, we propose grouping-based NOMA system. In the proposed scheme, all users are divided into two groups based on the distance between the BS and each user, where one utilizes the first half of the bandwidth and the other utilizes the rest in the orthogonal manner. On the other hand, users in each group share the spectrum in the non-orthogonal manner. Grouping users can reduce both the inter-user interference and residual interference due to the SIC error, so it can outperform conventional NOMA system, especially in case that the number of users and the SIC error increase. Based on that, we also present the hybrid operation of the conventional and the proposed NOMA systems. In numerical results, the total throughput of the proposed NOMA systems is compared with that of the conventional NOMA systems with regard to the number of users and SIC error. It is confirmed that the proposed NOMA system outperforms the conventional NOMA system as the number of users and the SIC error increase.

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Abstract

There has been a significant paradigm shift in the book industry from print to digital, with the increased use of electronic books (ebooks) on e-book readers. The major online booksellers and publishers are devoting their energies to the growth of the e-book market, resulting in an upward spiral in e-book usage, and a resultant increase in the number of downloaded e-books in an e-book reader library. However, there are comparatively few features for e-book management and search in most e-book reader libraries, particularly in smartphone environments. In addition, the user interfaces of e-book management in e-book readers are highly diverse, which has led to major usability issues. In this paper, we analyze user preferences for e-book management and search in the libraries of the five most commonly used e-readers for the Android smartphone platform via a questionnaire survey. Then, we suggest ideal alternatives in addition to user-friendly features based on user preferences for managing e-book libraries, to allow users to more easily browse collections, thereby enhancing the usability of e-book readers.

Gururaj Hanchinamani(BVB College of Engineering & Technology) ; Linganagouda Kulkarni(BVB College of Engineering & Technology) pp.56-69 https://doi.org/10.5392/IJoC.2015.11.4.056
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Abstract

This paper proposes an efficient image encryption scheme based on quintuple encryption using two chaotic maps. The encryption process is realized with quintuple encryption by calling the encrypt(E) and decrypt(D) functions five times with five different keys in the form EDEEE. The decryption process is accomplished in the reverse direction by invoking the encrypt and decrypt functions in the form DDDED. The keys for the quintuple encryption/decryption processes are generated by using a Tent map. The chaotic values for the encrypt/decrypt operations are generated by using a Gumowski-Mira map. The encrypt function E is composed of three stages: permutation, pixel value rotation and diffusion. The permutation stage scrambles all the rows and columns to chaotically generated positions. This stage reduces the correlation radically among the neighboring pixels. The pixel value rotation stage circularly rotates all the pixels either left or right, and the amount of rotation is based on chaotic values. The last stage performs the diffusion four times by scanning the image in four different directions: Horizontally, Vertically, Principal diagonally and Secondary diagonally. Each of the four diffusion steps performs the diffusion in two directions (forward and backward) with two previously diffused pixels and two chaotic values. This stage ensures the resistance against the differential attacks. The security and performance of the proposed method is investigated thoroughly by using key space, statistical, differential, entropy and performance analysis. The experimental results confirm that the proposed scheme is computationally fast with security intact.

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Abstract

The development of technology provides and increases security as well as convenience for humans. The development of new technology directly affects the standard of life thanks to smart home automatic control systems. This paper describes a door control, automatic curtain, home security (CCTV, fire, gas, safe, etc.), home control (energy, light, ventilation, etc.) and web-based smart home automatic controller. It also describes the use of ARM (Advanced RISC Machines) for automatic control of home equipment, a Multi-Axes Servo Controller using FPGA (Field Programmable Gate Array) and PLC (programmable logic controller). Additionally, it describes the development of a HTML editor using web auto control software. The tab loading time (7 seconds) is faster when using ARM-based web browser software instead of Chrome and Firefox is used because the browser has a small memory footprint (300M). This system is realized by web auto controller language which controls and uses PLCs that are easier than existing devices. This smart home automatic control technology can control smart home equipment anywhere and anytime and provides a remote interface through mobile equipment.

Dieu Ni Tran(Chonnam National University) ; Tuan Anh Tran(Chonnam National University,) ; Aran Oh(Chonnam National University) ; ; pp.77-85

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