• Journal of Korea Multimedia Society
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• v.14 no.5
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• pp.669-680
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• 2011

R-trees are widely used in various areas such as geographical information systems, CAD systems and spatial databases in order to efficiently index multi-dimensional data. As data sets used in these areas grow in size and complexity, however, range query operations on R-tree are needed to be further faster to meet the area-specific constraints. To address this problem, there have been various research efforts to develop strategies for acceleration query processing on R-tree by using the buffer mechanism or parallelizing the query processing on R-tree through multiple disks and processors. As a part of the strategies, approaches which parallelize query processing on R-tree through Graphics Processor Units(GPUs) have been explored. The use of GPUs may guarantee improved performances resulting from faster calculations and reduced disk accesses but may cause additional overhead costs caused by high memory access latencies and low data exchange rate between GPUs and the CPU. In this paper, to address the overhead problems and to adapt GPUs efficiently, we propose a novel approach which uses a GPU as a buffer to parallelize query processing on R-tree. The use of buffer algorithm can give improved performance by reducing the number of disk access and maximizing coalesced memory access resulting in minimizing GPU memory access latencies. Through the extensive performance studies, we observed that the proposed approach achieved up to 5 times higher query performance than the original CPU-based R-trees.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.62-70
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• 2015

Recently the demand for projected capacitance touch screens is sharply growing especially for large screens for medical devices, PC monitors and TVs. Large touch screens in general need a controller of higher complexity. They usually have a larger number of driving and sensing lines, and hence it takes longer to scan one frame for touch detection leading to a low frame scan rate. In this paper, a novel touch screen control technique is presented, which scans each frame in two steps of simultaneous multi-channel driving. The first step is to drive all driving lines simultaneously and determine which sensing lines have any touch. The second step is to sequentially rescan only the touched sensing lines, and determine exact positions of the touches. This technique can substantially increase the frame scan rate. This technique has been implemented using an FPGA and an AFE board, and tested using a commercial 23-inch touch screen panel. Experimental results show that the proposed technique improves the frame scan rate by 8.4 times for the 23-inch touch screen panel over conventional methods.

• Korean Journal of Clinical Pharmacy
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• v.29 no.2
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• pp.125-132
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• 2019

Objective: To examine the perceptions and attitudes toward spontaneous adverse drug reaction (ADR) reporting system among community pharmacists and identify factors that influence reporting, by implementing a survey. Methods: A structured questionnaire was developed and distributed online. Request for the survey was posted on the website of pharmacy's billing program, and the survey was conducted for 8 days. We collected the participants' response on their work environment, experience of ADR reporting, and their perception and attitude on the reporting system. Multivariate logistic regression was used to evaluate factors influencing ADR reporting. Results: A total of 382 pharmacists participated in the survey. Significant contributing factors for reporting level were age (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.84-0.96), knowledge of reporting method (OR, 53.56; 95% CI, 9.10-315.41), installation of reporting program (OR, 31.92; 95% CI, 4.16-244.75), and encouragement from the Korean pharmaceutical association (OR, 4.13; 95% CI, 1.11-15.35). Regarding the attitude toward spontaneous ADR reporting system, 'lack of time for reporting' (OR, 0.29; 95% CI, 0.15-0.53) and 'complexity of reporting procedure' (OR, 0.51; 95% CI, 0.31-0.84), were associated with a low likelihood of reporting. Conclusion: Our results indicated that the knowledge of ADR reporting method, installation of the reporting program, and encouragement from the Korean Pharmaceutical Association contribute to active reporting. It is necessary to simplify the reporting method, make the ADR reporting program user-friendly, and provide educational interventions to increase participation in spontaneous reporting by the community pharmacists.

• 한국노년학
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• v.28 no.4
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• pp.1147-1164
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• 2008

There has been a sharp increase in the number of grandmothers raising grandchildren in contemporary Korean society. However, little is known about the complexity of the experiences of the custodial grandparenting. Most of the studies mainly examined burden/cost and have paid little attention to the positive aspects of custodial grandparenting. In order to overcome this limitation of previous research, this study aims 1) to examine not only the costs but also the rewards of custodial grandparenting and to explore related factors, 2) to develop the typology based on relative rewards-burden perception of grandmothers about custodial grandparenting and explore the group differences. The data were gathered from 449 grandmothers raising their grandchildren as a primary caregiver, using a structured questionnaire. The data were analyzed using descriptive statistics, correlation, hierarchical multiple regression and ANOVA, with SPSS WIN 12.0 program. Main findings are as follows: First, custodial grandmothers report not only care-giving burden such as physical burnout and economic burden but also various rewards such as joy of watching their grandchildren grow and feeling good about themselves to be a help with their adult children, i.e. grandchildren's father or mother. Second, factors related to the level of perceived cost of grandparenting are different from the factors affecting the positive aspects of grandparenting. Third, results of the two by two cross-tab analysis based on the level of rewards and burden show that about 32 percent of the grandparents belong to Type II group(high rewards-low cost). This result is quite contrary to the assumption of previous research focusing mostly on cost and burden of custodial grandparenting. Fourth, four groups were different in terms of grandmother & grandchildren's characteristics. Implications of these results are discussed.

• Journal of The Korean Association For Science Education
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• v.39 no.1
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• pp.143-160
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• 2019

This study investigated 15 science teachers' perception and practice on free semester and science assessment. We analyzed frequencies of teacher choice for closed questions and used constant comparative method for teacher description and individual interview. Most teachers determined a low ranking for changes in assessment methods and mentioned a lack of objectivity on free semester assessment, unsystematic free semester assessment, and more importance on student activity and interest in science instruction. Most teachers understood process-based assessment as a direction of free semester assessment and teachers mentioned positive aspects for students or teacher difficulties dependent on their perception on process-based assessment. Half of the teachers failed to implement student self-assessment and student peer-assessment due to subjectivity and complexity. Some teachers did not provide feedbacks to students due to a lack of time and did not use certain assessment methods due to a lack of knowledge of the assessment. Teachers who did not have an experience of discussions in a teacher learning community mentioned reasons regarding a small number of the same grade teachers and inactive attitude of colleagues. Teachers who did not participate in professional development programs mentioned a lack of teacher understanding of free semester, participation of the teacher in charge, and teacher choice of participation as reasons.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.1-10
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• 2021

The interest in underwater acoustic sensor networks (UWASNs), along with the rapid development of underwater industries, has increased. To operate UWASNs efficiently, it is important to adopt well-designed medium access control (MAC) protocols that prevent collisions and allow the sharing of resources between nodes efficiently. On the other hand, underwater channels suffer from a narrow bandwidth, long propagation delay, and low data rate, so existing terrestrial node pairing schemes for non orthogonal multiple access (NOMA) cannot be applied directly to underwater environments. Therefore, a multi-dimensional node pairing scheme is proposed to consider the unique underwater channel in UWASNs. Conventional NOMA schemes have considered the channel quality only in node pairing. Unlike previous schemes, the proposed scheme considers the channel gain and many other features, such as node fairness, traffic load, and the age of data packets to find the best node-pair. In addition, the sender employs a list of candidates for node-pairs rather than path loss to reduce the computational complexity. The simulation results showed that the proposed scheme outperforms the conventional scheme by considering the fairness factor with 23.8% increases in throughput, 28% decreases in latency, and 5.7% improvements in fairness at best.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.2
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• pp.45-52
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• 2002

In this contributions, we propose a new MSB(most significant bit) algorithm based on AOP(All One Polynomial) and two parallel semi-systolic architectures to computes $AB^2$over finite field $GF(2^m)$. The proposed architectures are based on standard basis and use the property of irreducible AOP(All One Polynomial) which is all coefficients of 1. The proposed parallel semi-systolic architecture(PSM) has the critical path of $D_{AND2^+}D_{XOR2}$ per cell and the latency of m+1. The modified parallel semi-systolic architecture(WPSM) has the critical path of $D_{XOR2}$ per cell and has the same latency with PSM. The proposed two architectures, PSM and MPSM, have a low latency and a small hardware complexity compared to the previous architectures. They can be used as a basic architecture for exponentiation, division, and inversion. Since the proposed architectures have regularity, modularity and concurrency, they are suitable for VLSI implementation. They can be used as a basic architecture for algorithms, such as the Diffie-Hellman key exchange scheme, the Digital Signature Algorithm(DSA), and the ElGamal encryption scheme which are needed exponentiation operation. The application of the algorithms can be used cryptosystem implementation based on elliptic curve.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.10
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• pp.1517-1524
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• 2022

In this paper, we consider a heterogeneous network (HetNet) consisting of one macro base station and multiple small base stations, and assume the coordinated multi-point transmission between the base stations. In addition, we assume that the channel between the base station and the user consists of path loss and Rayleigh fading. Under these assumptions, we present the energy efficiency (EE) achievable by the user for a given base station and we formulate an optimization problem of dynamic cell selection and transmit power allocation to maximize the total EE of the HetNet. In this paper, we propose an unsupervised deep learning method to solve the optimization problem. The proposed deep learning-based scheme can provide high EE while having low complexity compared to the conventional iterative convergence methods. Through the simulation, we show that the proposed dynamic cell selection scheme provides higher EE performance than the maximum signal-to-interference-plus-noise ratio scheme and the Lagrangian dual decomposition scheme, and the proposed transmit power allocation scheme provides the similar performance to the trust region interior point method which can achieve the maximum EE.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.3
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• pp.1100-1118
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• 2021

In a wide range of ML applications, the training data contains privacy-sensitive information that should be kept secure. Training the ML systems by privacy-sensitive data makes the ML model inherent to the data. As the structure of the model has been fine-tuned by training data, the model can be abused for accessing the data by the estimation in a reverse process called model inversion attack (MIA). Although, MIA has been applied to shallow neural network models of recognizers in literature and its threat in privacy violation has been approved, in the case of a deep learning (DL) model, its efficiency was under question. It was due to the complexity of a DL model structure, big number of DL model parameters, the huge size of training data, big number of registered users to a DL model and thereof big number of class labels. This research work first analyses the possibility of MIA on a deep learning model of a recognition system, namely a face recognizer. Second, despite the conventional MIA under the white box scenario of having partial access to the users' non-sensitive information in addition to the model structure, the MIA is implemented on a deep face recognition system by just having the model structure and parameters but not any user information. In this aspect, it is under a semi-white box scenario or in other words a gray-box scenario. The experimental results in targeting five registered users of a CNN-based face recognition system approve the possibility of regeneration of users' face images even for a deep model by MIA under a gray box scenario. Although, for some images the evaluation recognition score is low and the generated images are not easily recognizable, but for some other images the score is high and facial features of the targeted identities are observable. The objective and subjective evaluations demonstrate that privacy cyber-attack by MIA on a deep recognition system not only is feasible but also is a serious threat with increasing alert state in the future as there is considerable potential for integration more advanced ML techniques to MIA.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.1
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• pp.64-71
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• 2024

The most critical aspect of full-arch prosthodontic treatment is evaluating whether the patient's vertical occlusal dimension is appropriate, and if necessary, restoring it through increasing vertical dimension. If the vertical occlusal dimension is too low, it can lead to reduced chewing efficiency, as well as not only aesthetic concerns but also potential issues like hyperactivity of muscles and posterior displacement of the mandible. This report is about the patient dissatisfied with pronunciation and aesthetics due to an inappropriate vertical occlusal dimension resulting from prior prosthetic interventions, underwent full-arch prosthodontic restoration treatment. Through the utilization of digital diagnostic apparatus, a comprehensive evaluation was undertaken for patient's vertical occlusal dimension, occlusal plane orientation, and the condition of prosthetic restorations. Through 3D facial scanning, the facial landmarks were discerned, and subsequently, the new occlusal plane was established. This provided the foundation for a digitally guided diagnostic wax-up. An elevation of 5 mm from the incisor was determined. Comprehensive dental rehabilitation was then executed for all remaining teeth, excluding the maxillary four incisors. The treatment protocol followed a systematic approach by initially creating implant-supported restorations on both sides of the dental arch to establish a stable occlusal contact. Subsequently, prosthetic restorations for the natural dentition were generated. Diagnostic and treatment planning were established through the utilization of facial scanning. This subsequently led to a reduction in treatment complexity and an expedited treatment timeline.