• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.39-44
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• 2013

Seat is the part relevant to comfortableness and safety among automotive parts directly. It also should have sufficient stiffness and strength to satisfy these conditions and ensure the safety of passenger. Automotive seat is modelled with 3D and is simulated with structural analyses about three kinds of experiments by before and after gap, side gap, before and after moment strength. As analysis result, deformation angles of $0.038^{\circ}$ and $0.04^{\circ}$ are respectively shown at before and after gap test, side gap test. Through before and after the moment strength test, maximum total deformations of 0.18946mm and 3.2482mm are respectively shown at front and rear loads. By the study result of no excessive deformation and no fracture at automotive seat frame, the sufficient rigidity and strength to guarantee the safety of passenger can be verified.

• Korean Institute of Interior Design Journal
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• v.15 no.1 s.54
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• pp.39-46
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• 2006

There lies more subjectivity in the methods and process of showing the Koreaness, and design methods cannot be defined with only one answer key, which is probable to cause much difficulty. Until now, the traditional Korean features have been tried by quite a few designers whose approaches deserves for the reference to understand the trends of expressing the Koreaness and develop the ways of its expression. Therefore, this study first considers the trial processes of design methods in reconsidering the Koreaness done by many artists in terms of previous studies and researches. Then this tries to make a frame to analyze the Koreaness theoretically after studying the approaches knowledge about traditional architecture designs widely used as design concepts, and to examine specific cases which reflects them in their interior architecture. All of these studies are aimed at get the understandings on trends and methods demonstrating the Koreaness in modern interior design. This study ranges from the artists, who have made efforts to express Koreaness in 1990s and after, to their artworks. As study methods, pre-study and reference researches had been done to examine the knowledge factors on the ground of the theory of D.G Jansson, to give a theory to the understanding of its methods and tendencies, and to build the frame for case analysis. As a result, in traditional architecture, spacial design gets the prominent priority and other factors are not far from different. In formative approachesthe expression inclination on material factor is outstanding. Consequently, these two approaches have analytic elements in difference but spacial design and materiality have prominently in common to express the Koreaness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4751-4755
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• 2011

This study investigates the plastic suspension assembly which is installed on inside of vehicle seat and support passenger's back to supply the comfortable ride performance. It aims to develop the structural design in order to support driver's back uniformly and assemble seat back frame with plastic suspension effectively. The part of suspension is designed by considering the body pressure distribution of driver and it has the same size as the practical model on simulation analysis. It is confirmed that the analysis result of plastic suspension approaches the practical measured values and the better body pressure distribution can be obtained as compared with the existing wire type.

• International Journal of High-Rise Buildings
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• v.7 no.4
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• pp.375-387
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• 2018

This paper presents a review on progressive collapse mechanism of steel framed buildings exposed to fire. The influence of load ratios, strength of structural members (beam, column, slab, connection), fire scenarios, bracing systems, fire protections on the collapse mode and collapse time of structures is comprehensively reviewed. It is found that the key influencing factors include load ratio, fire scenario, bracing layout and fire protection. The application of strong beams, high load ratios, multi-compartment fires will lead to global downward collapse which is undesirable. The catenary action in beams and tensile membrane action in slabs contribute to the enhancement of structural collapse resistance, leading to a ductile collapse mechanism. It is recommended to increase the reinforcement ratio in the sagging and hogging region of slabs to not only enhance the tensile membrane action in the slab, but to prevent the failure of beam-to-column connections. It is also found that a frame may collapse in the cooling phase of compartment fires or under travelling fires. This is because that the steel members may experience maximum temperatures and maximum displacements under these two fire scenarios. An edge bay fire is more prone to induce the collapse of structures than a central bay fire. The progressive collapse of buildings can be effectively prevented by using bracing systems and fire protections. A combination of horizontal and vertical bracing systems as well as increasing the strength and stiffness of bracing members is recommended to enhance the collapse resistance. A protected frame dose not collapse immediately after the local failure but experiences a relatively long withstanding period of at least 60 mins. It is suggested to use three-dimensional models for accurate predictions of whether, when and how a structure collapses under various fire scenarios.

• Physical Therapy Korea
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• v.31 no.2
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• pp.131-141
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• 2024

Background: Standing frames are a common intervention for children with cerebral palsy (CP), yet there is a lack of standardized dosing recommendations, impeding the enhancement of treatment outcomes in this population. Objects: This paper aims to optimize dosing strategies for standing frame programs in children with CP. It evaluates effective durations and frequencies for using standing frames to improve gait, hip joint integrity, functional activities, joint range of motion, and muscle tone. The goal is to provide evidence-based clinical recommendations to guide practitioners in treating pediatric CP patients. Methods: A comprehensive research was conducted across seven databases, yielding 23 studies meeting inclusion criteria. Strength of evidence was assessed using established tools. Clinical recommendations were formulated based on the amalgamation of existing evidence. Results: The paucity of evidence-based dosing recommendations for children with CP supported standing device is highlighted in this review. Key findings suggest that standing frames implemented 5 days per week demonstrate positive effects on gait (45 minutes/day, 3 times/week), hip joint integrity (60 minutes/day), functional activities (60 minutes/day in 30° to 60° of bilateral hip abduction), joint range of motion (60 minutes/day), and muscle tone (30 minutes/day). Conclusion: This systematic review of the treatment regimens for children with CP is providing useful insights to the dosing strategies of standing frames. The evidence supports a 30-60 minutes per day and 3-5 days a week intervention with specified durations for optimal outcomes. In enhancing the effectiveness of standing frames, as well as promoting evidence-based practices in the management of children with CP, these clinical recommendations offer guidance for practitioners.

• Journal of the Korean Society for information Management
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• v.24 no.4
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• pp.53-72
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• 2007

This study is designed to assess whether storyboard surrogates are useful enough to be utilized for indexing sources as well as for metadata elements using 12 sample videos and 14 participants. Study shows that first, the match rates of index terms and summaries are significantly different according to video types, which means storyboard surrogates are especially useful for the type of videos of conveying their meanings mainly through images. Second, participants could assign subject keywords and summaries to digital video, sacrificing a little loss of full video clips' match rates. Moreover, the match rate of index terms (0.45) is higher than that of summaries (0.40). This means storyboard surrogates could be more useful for indexing videos rather than summarizing them. The study suggests that 1)storyboard surrogates can be used as sources for indexing and abstracting digital videos; 2) using storyboard surrogates along with other metadata elements (e.g., text-based abstracts) can be more useful for users' relevance judgement; and 3)storyboard surrogates can be utilized as match sources of image-based queries. Finally, in order to improve storyboard surrogates quality, this study proposes future studies: constructing key frame extraction algorithms and designing key frame arrangement models.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2A
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• pp.154-167
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• 2006

Today's IEEE 802.11 WLANs(Wireless LANs) provide multiple transmission rates so that different rates can be exploited in an adaptive manner depending on the underlying channel condition in order to maximize the system performance. Many rate adaptation schemes have been proposed so far while most(if not all) of the commercial devices implement a simple open-loop rate adaptation scheme(i.e., without feedback from the receiver), called ARF(Automatic Rate Fallback) due to its simplicity. A key problem with such open-loop rate adaptation schemes is that they do not consider the collision effect, and hence, malfunction severely when many transmission failures are due to collisions. In this paper, we propose a novel rate-adaptation scheme, called CARA(Collision-Aware Rate Adaptation). The key idea of CARA is that the transmitter station combines adaptively the Request-to-Send/Clear-to-Send(RTS/CTS) exchange with the Clear Channel Assessment(CCA) functionality to differentiate frame collisions from frame transmission failures cause by channel errors. Therefore, compared with other open-loop rate adaptation schemes, CATA is more likely to make the correct rate adaptation decisions. Through extensive simulation runs, we evaluate our proposed scheme to show that our scheme yields significantly higher throughput performance than the existing schemes in both static and time-varying fading channel environments.

• Journal of Communications and Networks
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• v.12 no.4
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• pp.289-307
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• 2010

The problem of model selection arises in a number of contexts, such as subset selection in linear regression, estimation of structures in graphical models, and signal denoising. This paper studies non-asymptotic model selection for the general case of arbitrary (random or deterministic) design matrices and arbitrary nonzero entries of the signal. In this regard, it generalizes the notion of incoherence in the existing literature on model selection and introduces two fundamental measures of coherence-termed as the worst-case coherence and the average coherence-among the columns of a design matrix. It utilizes these two measures of coherence to provide an in-depth analysis of a simple, model-order agnostic one-step thresholding (OST) algorithm for model selection and proves that OST is feasible for exact as well as partial model selection as long as the design matrix obeys an easily verifiable property, which is termed as the coherence property. One of the key insights offered by the ensuing analysis in this regard is that OST can successfully carry out model selection even when methods based on convex optimization such as the lasso fail due to the rank deficiency of the submatrices of the design matrix. In addition, the paper establishes that if the design matrix has reasonably small worst-case and average coherence then OST performs near-optimally when either (i) the energy of any nonzero entry of the signal is close to the average signal energy per nonzero entry or (ii) the signal-to-noise ratio in the measurement system is not too high. Finally, two other key contributions of the paper are that (i) it provides bounds on the average coherence of Gaussian matrices and Gabor frames, and (ii) it extends the results on model selection using OST to low-complexity, model-order agnostic recovery of sparse signals with arbitrary nonzero entries. In particular, this part of the analysis in the paper implies that an Alltop Gabor frame together with OST can successfully carry out model selection and recovery of sparse signals irrespective of the phases of the nonzero entries even if the number of nonzero entries scales almost linearly with the number of rows of the Alltop Gabor frame.

• The Journal of the Korea Contents Association
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• v.6 no.9
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• pp.98-107
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• 2006

By improving performance of mobile machine(3D engine, 3D accelerator chip set, etc) and developing wireless network technology, a demand for actual contents of users is being increased rapidly. But, there are some difficulties yet for the speedy development of actual contents because of the limitation of development resources that is dependent on each mobile device's different performance. In general, much of the animated character-creation work for mobile environment is still done manually by experienced animator with the method of key frame processing. However, it needs a lot of time and more costs for creating motion. Additionally, it is possible to cause a distortion of motion. In this paper, I solved the difficulties by using a optical motion capture system, it was able to acquire accurate motion data more easily and quickly, and then it was possible to make 3D dance contents efficiently. Also, I showed techniques of key reduction and controlling frame number for using huge amounts of motion capture data in mobile environment which requires less resources. In making 3D dance contents, using an optical motion capture system was verified that it was more efficient to make and use actual-reality contents by creating actual character motion and by decreasing processing time than existing method.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.4
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• pp.367-375
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• 2002

Inverse kinematics is a very useful method for control]ing the posture of an articulated body. In most inverse kinematics processes, the major matter of concern is not the posture of an articulated body itself but the position and direction of the end effector. In some applications such as 3D character animations, however, it is more important to generate an overall natural posture for the character rather than place the end effector in the exact position. Indeed, when an animator wants to modify the posture of a human-like 3D character with many physical constraints, he has to undergo considerable trial-and-error to generate a realistic posture for the character. In this paper, the Inductive Inverse Kinematics(IIK) algorithm using a Uniform Posture Map(UPM) is proposed to control the posture of a human-like 3D character. The proposed algorithm quantizes human behaviors without distortion to generate a UPM, and then generates a natural posture by searching the UPM. If necessary, the resulting posture could be compensated with a traditional Cyclic Coordinate Descent (CCD). The proposed method could be applied to produce 3D-character animations based on the key frame method, 3D games and virtual reality.