• Journal of Computing Science and Engineering
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• v.11 no.2
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• pp.69-77
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• 2017

Recent GPUs have adopted cache memory to benefit general-purpose GPU (GPGPU) programs. However, unlike CPU programs, GPGPU programs typically have considerably less temporal/spatial locality. Moreover, the L1 data cache is used by many threads that access a data size typically considerably larger than the L1 cache, making it critical to bypass L1 data cache intelligently to enhance GPU cache performance. In this paper, we examine GPU cache access behavior and propose a simple hardware-based GPU cache bypassing method that can be applied to GPU applications without recompiling programs. Moreover, we introduce a hybrid method that integrates static profiling information and hardware-based bypassing to further enhance performance. Our experimental results reveal that hardware-based cache bypassing can boost performance for most benchmarks, and the hybrid method can achieve performance comparable to state-of-the-art compiler-based bypassing with considerably less profiling cost.

• Proceedings of the Korea Database Society Conference
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• 1997.10a
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• pp.515-523
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• 1997

Maintaining materialized views and/or replica can basically be considered as a client-sewer architecture that extracts the changes of the distributed source data and transfers them to the relevant target sites. View maintenance and materialized views are considered to be important for suggesting solutions to the problems such as a decision support, active databases, a data warehouse, temporal databases, internet applications, etc. In this paper an analysis is addressed that formulates the cost functions and evaluates them as the propagation subjects, objects, and update policies. The propagation subject can be the client side, sewer side, and the third: and the objects can be base tables, semi-base tables, and delta files: And the update policies can be the immediate, deferred and periodic ones, respectively.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.9
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• pp.799-806
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• 2007

Direct Numerical Simulation was carried out to predict mass transfer in turbulent flow around a rotating stepped cylinder. This investigation is a follow-up study of DNS of turbulent flow in Nesic et al. [Corrosion, Vol. 56, No. 10, pp. 1005 - 1014] The original motivation of this work stemmed from the efforts to design a simple device which can generate flows of high turbulence intensity at low cost for corrosion researchers. Two cases were considered; Sc=1 and 10 both at Re=335. Here, Sc and Re stand for Schmidt number and Reynolds number, respectively, based on the step height and the surface speed of the cylinder upstream of the step. Main focus was placed on the correlation between turbulence and mass transfer. The spatio-temporal evolution of concentration field is discussed. The numerical results are qualitatively compared with those of the experiment conducted with a similar flow configuration.

• Architectural research
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• v.7 no.1
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• pp.1-9
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• 2005

The needs of collaboration among design participants spread in different locations is emphasized in the early design stage in order to not only save time and provide places to meet and talk, but also to save cost for those events as well: This is being realized by the Internet, which helps support a networked, integrated real-time multi-user environment. As the base for collaboration activities moves from physical places to cyberspace, the methods of connecting every participant by means of a computer technology have been desired and considered. This study aims at investigating today's collaboration technology in the architectural design process, especially focused on the early stages, in terms of temporal dimensions. In addition, major concepts for and previous efforts and tools of collaborative design have been examined, and a specific recommendation has been proposed for future development of collaborative architectural design systems: That is distributed collaboration, which is accessible and comprehensible to all the professionals in the building design team, which not only allows the sharing of information but also the sharing of understanding, and which facilitates the development of design tools for different aspects of the envisioned collaborative design environment.

• Journal of Ocean Engineering and Technology
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• v.32 no.1
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• pp.62-67
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• 2018

A wave buoy commonly used for measurements in marine environments is very useful for measurements on the sea surface wind and waves. However, it is constantly exposed to external forces such as typhoons and the risk of accidents caused by ships. Therefore, the installation and maintenance charges are large and constant. In this study, we developed a system for monitoring the sea surface wind using marine radar to provide spatial and temporal information about sea surface waves at a small cost. The essential technology required for this system is radar signal processing. This paper also describes the analytical process of using it for monitoring the sea surface wind. Consequently, developing this system will make it possible to replace wave buoys in the near future.

• Journal of Forest and Environmental Science
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• v.32 no.1
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• pp.55-67
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• 2016

This paper investigated policies that drive the sustainable management of Ivorian forest which disappear at an annual rate of 250000 hectares. Based on an inter-temporal model for optimum allocation of forest land to three competing uses, the article found that sustainability depends on the incentive structure, of which forest taxes and fees are a key, though obviously not the sole, component. The study proposed to increase the area fee level by accounting for environmental externalities generated by forest harvesters and farmers. The paper showed that the area fee is a decreasing function of the forest natural rate of regeneration and the reconversion rate of agricultural surfaces. Finally, at the given forest natural rate of regeneration and the reconversion rate of agricultural surfaces, the model argued that the area fee need to be progressive (arithmetic progression) in the context of ecological equilibrium break while it should remain constant in normal situation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.455-459
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• 1997

A methodology which supports the feature used from design to manufacturing for sculptured pocket is newly devlored and present. The information contents in a feature can be easily conveyed from one application to another in the manufacturing domain. However, the feature generated in one application may not be directly suitable for another whitout being modified with more information. Theobjective of the paper is to parsent the methodology of decomposing a bulky feature of sculptured pocket to be removed into compact features to be efficiently machined. In particular, the paper focuses on the two task: 1) to segment horizontally a bulky feature into intermediate features by determining the adequate depth of cut and cutter size and to generate the temporal precedence graph of the intermediate features and 2)to further decompose each intermediate feature vertical into smaller manufacturing features and to apply the variable feed rate to each small feature. The proposed method will provid better efficiency in machining time and cost than the classical method which uses a long string of NC codes necessary to remove a bulky fecture.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.512-519
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• 2002

In this paper, we implemented a loom component to be placed in a window and a looms management system which is able to connect database and to process various queries. The implemented system has aggregate query p개cessing functions for the loom components existing in the selected area by the mouse and it also has high level query processing functions represented with chart and pivot table; it can be used as a decision support system. The proposed system can detect temporal or persistent problems of the looms. Therefore it can be used to raise the productivity and to reduce the cost in textile companies by coping with the situation properly.

• Smart Structures and Systems
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• v.19 no.4
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• pp.383-391
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• 2017

In this paper, we investigate the impacts of network topology on the performance of a distributed estimation algorithm, namely combine-then-adaptive (CTA) diffusion LMS, based on the data with or without the assumptions of temporal and spatial independence with noisy links. The study covers different network models, including the regular, small-world, random and scale-free whose the performance is analyzed according to the mean stability, mean-square errors, communication cost (link density) and robustness. Simulation results show that the noisy links do not cause divergence in the networks. Also, among the networks, the scale free network (heterogeneous) has the best performance in the steady state of the mean square deviation (MSD) while the regular is the worst case. The robustness of the networks against the issues like node failure and noisier node conditions is discussed as well as providing some guidelines on the design of a network in real condition such that the qualities of estimations are optimized.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.5A
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• pp.726-742
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• 2000

A novel rte control algorithm consisting of two major components, i.e. a variable encoding frame rate method and a hybrid DCT/wavelet I-frame coding scheme, is proposed in this work for low bit rate video coding. Most existing rate control algorithms for low bit rate video focus on bit allocation at the macroblock level under a constant frame rate assumption. The proposed rate control algorithm is able to adjust the encoding frame rate at the expense of tolerable time-delay. Furthermore, an R-D optimized hybrid DCT/wavelet scheme is used for effective I-frame coding. The new rate-control algorithm attempts to achieve a good balance between spatial quality and temporal quality to enhance the overall human perceptual quality at low bit rates. It is demonstrated that the rate control algorithm achieves higher coding efficiency at low bit rates with a low additional computational cost. The variable frame rate method and hybrid I-frame coding scheme are compatible with the bi stream structure of H.263+.