• Journal of Communications and Networks
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• v.14 no.2
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• pp.206-212
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• 2012

In this paper, in order to effectively apply unitary space-time modulation to the direct-sequence spread-spectrum multiple-access (DSSS-MA) networks, we propose a low-rate, noncoherent, unitary, and space-time modulated DSSS system supporting any number of transmit antennas based on Walsh matrices. The proposed scheme simultaneously performs bandwidth spreading and space-time coding and outperforms those using high-rate, conventional unitary space-time constellations. Furthermore, the proposed scheme allows for a simple detector structure based on fast Walsh transforms.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.3
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• pp.109-124
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• 2016

The objective of this paper is to find the density, stiffness, and strength of truss-wall diamond corrugation model combined with pinwheel truss inside space. The truss-wall diamond corrugation (TDC) model is defined as a unit cell coming from solid-wall diamond corrugation (SDC) model. Pinwheel truss-wall diamond corrugation (P-TDC) model is made by TDC connected with pinwheel structure inside of the space. Derived ideal solutions of P-TDC is based on truss-wall and pinwheel truss model at first. And then it is compared with Gibson-Ashby's ideal solution. To validate the ideal solutions of the P-TDC, ABAQUS software is used to predict the density, strength, and stiffness, and then each of them are compared to the ideal solution of Gibson-Ashby with a log-log scale. Applied material property is stainless steel 304 because of having cost effectiveness. Applied parameters for P-TDC are 1 thru 5 mm diameter within fixed opening width as 4mm. In conclusion, the relative Young's modulus and relative yield strength of the P-TDC unit model is reasonable matched to the ideal expectations of the Gibson-Ashby's theory. In nearby future, P-TDC model is hoped to be applied to make sandwich core structure by advanced technologies such as 3D printing skills.

• Journal of the Institute of Convergence Signal Processing
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• v.3 no.1
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• pp.87-92
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• 2002

Placement is an important step in the physical design of VLSI circuits. It is the problem of placing a set of circuit modules on a chip to optimize the circuit performance. The most popular algorithms for placement include the cluster growth, simulated annealing and integer linear programming. In this paper we propose a stochastic evolution algorithm searching solution space for the placement problem, and then compare it with simulated annealing by analyzing the results of each implementation.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_1
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• pp.149-161
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• 2020

We describe a new approach to implement of trajectory control and track record of articulated manipulator based on monitoring simulator for smart factory. The learning control algorithm was applied in implementation real-time control to provide enhanced motion control performance for robotic manipulators. The proposed control scheme is simple in structure, fast in computation, and suitable for real-time control. Moreover, this scheme does not require any accurate dynamic modeling, or values of manipulator parameters and payload. Performance of the proposed controller is illustrated by simulation and experimental results for robot manipulator consisting of six joints at the joint space and Cartesian space.by monitoring simulator.

• International Journal of Advanced Culture Technology
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• v.7 no.2
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• pp.113-124
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• 2019

Stanley Kubrick's 1968 film titled 2001: A Space Odyssey has generally been considered as a monumental piece of mainstream epic science-fiction. However, this film can be evaluated as having properties of experimental cinema by boldly trying technical innovation and aesthetic experiment in various aspects. From the filmmaker's process to filmic structure, technical innovations, screening method, $mise-en-sc\grave{e}ne$, cinematic style and its (auto-)reflexivity, 2001: A Space Odyssey is highly experimental. We will attempt to separate out aspects of 2001: A Space Odyssey that derive explicitly from traditions in experimental cinema, whether adopting those traditions or innovating within them, by identifying the film's experimental strategies and relating them to other experimental films that came before and after. This will show that the purely formal characteristics of the film's conception carry meanings on their own relating to Kubrick's personal expression, ideas about cinema and philosophy that go beyond the scope of the film's narrative.

• Korea Science and Art Forum
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• v.34
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• pp.133-148
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• 2018

Korea's housing structure is predicted that one-person housing will be the most common type of housing in Korea. Therefore, this study intends to derive contents for designing a one-person housing space considering the life of a rapidly increasing one-person householder. For this purpose, this study objectively derives the social, economic and cultural influencing factors of one-person households through big data analysis, and analyzed the correlation between contents using social network analysis methodology. In this paper, 60 core contents related to one person housing space were derived by applying big data analysis methodology. And through social network analysis, the most influential contents were derived from the space editing and space composition categories. This means that the residential space is an important part of the design idea that can flexibly respond to changes in the user's life. Based on this study, future research will focus on the concept and design methodology of one-person housing space.

• Journal of Computing Science and Engineering
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• v.11 no.1
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• pp.32-38
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• 2017

Determining the correct word sense among ambiguous senses is essential for semantic analysis. One of the models for word sense disambiguation is the word space model which is very simple in the structure and effective. However, when the context word vectors in the word space model are merged into sense vectors in a sense inventory, they become typically very large but still suffer from the lexical scarcity. In this paper, we propose a word sense disambiguation method using word embedding that makes the sense inventory vectors compact and efficient due to its additive compositionality. Results of experiments with a Korean sense-tagged corpus show that our method is very effective.

• Journal of information and communication convergence engineering
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• v.21 no.2
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• pp.117-129
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• 2023

High-utility itemset mining (HIUM) has emerged as a key data-mining paradigm for object-of-interest identification and recommendation systems that serve as frequent itemset identification tools, product or service recommendation systems, etc. Recently, it has gained widespread attention owing to its increasing role in business intelligence, top-N recommendation, and other enterprise solutions. Despite the increasing significance and the inability to provide swift and more accurate predictions, most at-hand solutions, including frequent itemset mining, HUIM, and high average- and fast high-utility itemset mining, are limited to coping with real-time enterprise demands. Moreover, complex computations and high memory exhaustion limit their scalability as enterprise solutions. To address these limitations, this study proposes a model to extract high-utility frequent closed itemsets based on an improved cumulative summary list structure (CSLFC-HUIM) to reduce an optimal set of candidate items in the search space. Moreover, it employs the lift score as the minimum threshold, called the cumulative utility threshold, to prune the search space optimal set of itemsets in a nested-list structure that improves computational time, costs, and memory exhaustion. Simulations over different datasets revealed that the proposed CSLFC-HUIM model outperforms other existing methods, such as closed- and frequent closed-HUIM variants, in terms of execution time and memory consumption, making it suitable for different mined items and allied intelligence of business goals.

• Journal of Digital Convergence
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• v.15 no.1
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• pp.11-22
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• 2017

The purpose of the study is to come up with counter plans to the spatial change caused by an aging society. To achieve the purpose of this study, research methods are conducted in the literature survey and the census data are compared. This study focuses on an aging society, the current status of space and related problems, based on political economic spatial concepts, and then presents five countermeasures as follows. First, the planning considering the aging populations. Second, increase in total fertility rate and increase population absorption. Third, increased economic vitality of the elderly due to increased participation in the production of senior citizens. Forth, establishment and implementation of regional development plan for the elderly. Fifth, needs to transform the spatial policies of the aged to prepare a large gap in space. The result of this paper proposes the need to change the living space policies and planning to avoid mismatching between them, reducing the aging speed simultaneously. The study is expected to contribute to the establishment of a space plan for areas where the aging population is rapidly increasing.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.9
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• pp.794-806
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• 2017

It is essential to protect the national space assets and space environment safely as a space development country from the continuously increasing space debris. And Active Debris Removal(ADR) is the most active way to solve this problem. In this paper, we studied the Artificial Neural Network(ANN) for a stable recognition model of vision-based space debris tracking system. We obtained the simulated image of the space environment by the KARICAT which is the ground-based space debris clearing satellite testbed developed by the Korea Aerospace Research Institute, and created the vector which encodes structure and color-based features of each object after image segmentation by depth discontinuity. The Feature Vector consists of 3D surface area, principle vector of point cloud, 2D shape and color information. We designed artificial neural network model based on the separated Feature Vector. In order to improve the performance of the artificial neural network, the model is divided according to the categories of the input feature vectors, and the ensemble technique is applied to each model. As a result, we confirmed the performance improvement of recognition model by ensemble technique.