• Journal of the Ergonomics Society of Korea
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• v.18 no.3
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• pp.127-140
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• 1999

In order to apply three-dimensional images to industries, the possibility of realizing three-dimensional images should be ensured and when operating a task using three-dimensional images, the intention of the observer and the result of operation should be precisely related. The aim of this paper is to investigate the task performance of a human operator during operating a robot manipulator using three-dimensional and two-dimensional image displays. From the result of this research, it was found that the accuracy of robot operation in the case of using three-dimensional displays is much higher than in the case of using two-dimensional displays and the adapting time to the operating task using three-dimensional displays is shorter than that using two-dimensional displays. From such results, we concluded that the application of three-dimensional displays, which can closely reflect real environment, to industries is desirable.

• Geomechanics and Engineering
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• v.21 no.5
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• pp.413-422
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• 2020

The choice of eco-friendly materials for ground improvement is a necessary way forward for sustainable development. Adapting naturally available biopolymers will render the process of soil stabilization carbon neutral. An attempt has been made to use β-glucan, a natural biopolymer for the stabilization of lean clay as a sustainable alternative with specific emphasis on comprehending the effect of confining stresses on lean clay through triaxial compression tests. A sequence of laboratory experiments was performed to examine the various physical and mechanical characteristics of β-glucan treated soil (BGTS). Micro-analysis through micrographs were used to understand the strengthening mechanism. Results of the study show that the deviatoric stress of 2% BGTS is 12 times higher than untreated soil (UTS). The micrographs from Scanning Electron Microscopy (SEM) and the results of the Nitrogen-based Brunauer Emmett Teller (N₂-BET) analysis confirm the formation of new cementitious fibres and hydrogels within the soil matrix that tends to weld soil particles and reduce the pore spaces leading to an increase in strength. Hydraulic conductivity (HC) and compressibility reduced significantly with the biopolymer content and curing period. Results emphases that β-glucan is an efficient and sustainable alternative to the traditional stabilizers like cement, lime or bitumen.

• Journal of Korea Multimedia Society
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• v.18 no.9
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• pp.1091-1097
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• 2015

Internet-of-Things (IoT) becomes one of the most promising future paradigms, which foresees enormous amounts of interoperable things and heterogeneous services. The goal of IoT is to enable all things connected and brings all kinds information and services to people. However, such a great deal of information may lead to cognitive overload or restrain in productivity of people. Thus, it is a necessity to build intelligent mechanisms to assist people in accessing the information or services they needed in a proactive manner. Most of previous related mechanisms are built on well-defined web services and lack of consideration of constrained resources. This paper suggests a services composition method by adapting a hierarchical model, which is a graph-based model composed of four layers: Context Layer, Event Layer, Service Layer and Device Layer. With a such multi-layer graph, service composition can be achieved by the iteration of layer by layer. Then, to evaluate the effectiveness of this proposed hierarchical model, a real-life emergency response dataset is applied and the experimental results are composed with the general probabilistic method and indicate that the proposed method is help for compositing multiple services while considering given context and constrained resources.

• Journal of Environmental Policy
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• v.12 no.3
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• pp.73-96
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• 2013

This aim is to explore the change of lifestyle caused by climate change and develop available adaptation policies against climate threats in Central Asia with the perspective of nomadism, which depends entirely on natural ecosystem. This article also attempts to pinpoint the dynamics between nomadic lifestyle and adaptation options for the resilience of nomadic community against climatic change threats. The adaptation options and opportunities as well as the impacts of land use change and nomadic pastoralists' lifestyle caused by climate change cannot be overemphasized. We suggest that nomadic lifestyle may aggravate the degree of vulnerability to climate change threats, whereas the capacity of nomad to successfully adapting to new environment in developing countries can be superior to that of settler lifestyle in one place in developed countries.

• Journal of Computational Design and Engineering
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• v.3 no.3
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• pp.250-265
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• 2016

Owing to our rapidly aging society, accessibility evaluation to enhance the ease and safety of access to indoor and outdoor environments for the elderly and disabled is increasing in importance. Accessibility must be assessed not only from the general standard aspect but also in terms of physical and cognitive friendliness for users of different ages, genders, and abilities. Meanwhile, human behavior simulation has been progressing in the areas of crowd behavior analysis and emergency evacuation planning. However, in human behavior simulation, environment models represent only "as-planned" situations. In addition, a pedestrian model cannot generate the detailed articulated movements of various people of different ages and genders in the simulation. Therefore, the final goal of this research was to develop a virtual accessibility evaluation by combining realistic human behavior simulation using a digital human model (DHM) with "as-is" environment models. To achieve this goal, we developed an algorithm for generating human-like DHM walking motions, adapting its strides, turning angles, and footprints to laser-scanned 3D as-is environments including slopes and stairs. The DHM motion was generated based only on a motion-capture (MoCap) data for flat walking. Our implementation constructed as-is 3D environment models from laser-scanned point clouds of real environments and enabled a DHM to walk autonomously in various environment models. The difference in joint angles between the DHM and MoCap data was evaluated. Demonstrations of our environment modeling and walking simulation in indoor and outdoor environments including corridors, slopes, and stairs are illustrated in this study.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.245-248
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• 2005

Wireless LANs based on the IEEE 802.11 standard are widely spread for use nowadays. Traffic which are conveyed over the WLANs change rapidly from normal data such as Email and Web pages, to multimedia data of high resolution video and voice. To meet QoS (Quality of Service) required by these multimedia traffic, the IEEE 802 committee recently has developed a new standard, IEEE 802.11e. Current IEEE 802.11e, however, is not sufficient to support service differentiations and network performance enhancements, under a varying network environment experiencing as varying channel characteristics and high network loads. Recently, there have been much research to complement this deficiency of 802.11e standard. This paper surveys these research efforts.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1183-1186
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• 1998

Adaptive nois canceller can extract the noiseremoved spech in noisy speech signal by adapting the filter-coefficients to the background noise environment. A kind of LMS algorithm is one of the most popular adaptive algorithm for noise cancellation due to low complexity, good numerical property and the merit of easy implementation. However there is the matter of increasing misadjustment at voiced speech signal. Therefore the demanded speech signal may be extracted. In this paper, we propose a fast and noise robust wavelet packet adaptive noise canceller with NLMS-SUM method LMS combined algorithm. That is, we decompose the frequency of noisy speech signal at the base of the proposed analysis tree structure. NLMS algorithm in low frequency band can efficiently dliminate the effect of the low frequency noise and SUM method LMS algorithm at each high frequency band can remove the high frequency nosie. The proposed wavelet packet adaptive noise canceller is enhanced the more in SNR and according to Itakura-Satio(IS) distance, it is closer to the clean speech signal than any other previous adaptive noise canceller.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.56-59
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• 1998

The rapid diffusion of the Internet and the World Wide Web is facilitating greater interaction - and potential opportunities for customization - between vendors and customers. For instance, virtual reality and multimedia technologies allow consumers to envision their designed products. The increasing pace of the business environment highlights the need to deploy intelligent systems in all stages of product design and production planning. This paper deals with a system to generate an appropriate product design by adapting customer preferences and constraints using the case based reasoning methodology. Moreover, intelligent agents are integrated with virtual reality technology to provide a friendly user interface.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.3
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• pp.7-12
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• 2008

Today, manufacturers are forced to acknowledge that the life cycles of products are becoming shorter. In the case of the door trim assembly field, the highly frequent introduction of new products and the continuous increase in product varieties leads to the demand for redesigning assembly systems more often. Modular manufacturing systems can be an important issue in helping to overcome these problems. This paper presents the development of a modular assembly system for the door trim, and because it takes the change drives into consideration, this system is highly flexible in adapting to changes in the environment.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.4
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• pp.125-131
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• 2000

In order to collect basic data for the plan, design, and improvement of teenager leisure space as well as to contribute to the preparation of various youth leisure spaces, this study is to examine and analyze leisure space planning factors under the consideration of leisure patterns changing rapidly in youth activities. We used sufficient amount of questionnaires and a physical environment analysis at downtown parks and Tongdaemun fashion complexes where various leisure activities of teenager are happened. In addition, an importance and performance analysis was attempted on planning factors of each derived leisure space. on sequently, effective and efficient preparation of youth leisure space for desirable youth leisure activities should be carried out after finding out characteristics of teenager leisure spaces, deriving and integrating suitable planning factors for each characteristics, and finally adapting such derived planning factors by performance and importance. The future space for youth leisure should be improved and prepared after mature consideration about importance and performance of planning factors, which are suited for leisure patterns and characteristics of teenager leisure spaces.