• Journal of KIISE:Databases
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• v.31 no.6
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• pp.675-683
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• 2004

In main-memory resident index structures, secondary cache misses considerably have an effect on the performance of index structures. Recently, several main-memory resident index structures that consider cache have been proposed to reduce the impact of secondary cache misses. However they still suffer from full secondary cache misses whenever visiting each level of a index tree. In this paper, we propose a new index structure that eliminates cache misses even when visiting each level of index tree. The proposed index structure prefetches the grandchildren of a current node. The basic structure of the proposed index structure is from CSB+-tree that uses the concepts of the node group to increase fan-out. However the insert algorithm of the proposed index structure reduces the cost of a split significantly. Also, we show the superiority of our algorithm through various performance evaluation.

• The KIPS Transactions:PartB
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• v.12B no.2 s.98
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• pp.131-136
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• 2005

Motion Estimation (ME) has been developed to remove redundant data contained in a sequence of image. And ME is an important part of video encoding systems, since it can significantly affect the qualify of an encoded sequences. Generally, ME consists of two stages, the integer pixel motion estimation and the half pixel motion estimation. Many methods have been developed to reduce the computational complexity at the integer pixel motion estimation. However, the studies are needed at the half pixel motion estimation to reduce the complexity. In this paper, a method based on the correlations between integer pixel motion vectors and half pixel motion vectors is proposed for the half pixel motion estimation. The proposed method has less computational complexity than the full half pixel search method (FHSM) that needs the bilinear interpolation of half pixels and examines nine half pixel points to the find the half pixel motion vector. Experimental results show that the speedup improvement of the proposed method over FHSM can be up to $2.5\~80$ times faster and the image quality degradation is about to $0.07\~0.69(dB)$.

• Journal of the Korean Society of Safety
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• v.34 no.6
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• pp.76-87
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• 2019

This study was conducted to check the cabin crew's safety perception in relation to the airline's safety climate and cabin crew's safety action and to verify that the safety perception's mediation effects. The results of the study confirmed that all three factors of the safety climate have a significant impact on safety perception, and among them, safety practice is the most significant. Accordingly, Airlines need to establish a community that enables real-time information exchange for air accidents so that the cabin crew can present real-time examples of safety-related accidents. In addition, it will be necessary to work with external safety agencies to form an active attitude for the establishment of safety procedures in order to prevent recurrence of safety problems while considering the causes of such incidents internally in the event of an airline safety accident. In addition, it was confirmed that safety training was the most significant factor to safety action, among which all three elements of the safety climate had a significant effect on safety action. Therefore, airlines need to expand practical training on aircraft to full-scale safety training to build an immediate resolution for cabin crews in the event of an air accident. In addition, safety training should be established to encourage collaboration among aviation safety-related personnel to participate in safety training together to address aviation safety from a diverse point of view. Safety perception was has a significant effect on safe action. Therefore, airlines should reinforce the airline's safety management system by checking the status of the cabin crew's safety perception extending the level of punishment to the scope of retirement or disqualification to establish a firm awareness of safety. Finally, the safety perception has demonstrated partial mediation effects in relation to the safety climate and safety action. Therefore, the airline needs to improve the duties of the cabin crew that interferes with cabin safety duties. In addition, airlines should utilize advertisements emphasizing that safety is first.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.4
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• pp.213-225
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• 2007

Flash memory is widely used as a storage device for potable equipments such as digital cameras, MP3 players and cellular phones because of its characteristics such as its large volume and nonvolatile feature, low power consumption, and good performance. However, a block in flash memories should be erased to write because of its hardware characteristic which is called as erase-before-write architecture. The erase operation is much slower than read or write operations. FTL is used to overcome this problem. We compared the performance of the existing FTL algorithms on Windows-based OS. We have developed a tool called FTL APAT in order to gather I/O patterns of the disk and analyze the performance of the FTL algorithms. It is the log buffer scheme with full associative sector translation(FAST) that the performance is best.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.6
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• pp.514-530
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• 2005

This paper proposes a compact eAI framework for the integration of various types of applications deployed on different platforms in the Internet. The applications are connected and invoked to achieve a business goal by the coordination of the workflow system in the framework. for the construction of the framework, five sub-modules are elicited and the functions and roles of each module are defined. The elicited five sub-modules include business process modeling tool, eAI platform, business processes transform module, UDDI connection module, and workflow system. In the framework, intra and inter organizational applications can be integrated together across firewalls. In this paper, the extension of a workflow system to implement the framework is also described in detail and the usefulness of the framework is ascertained by implementing an application process within the framework. A full-fledged eAI solution can be constructed by gradually adding supplementary functions within this framework.

• Journal of KIISE:Software and Applications
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• v.31 no.2
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• pp.213-223
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• 2004

In this paper, we propose a new face detection method for real-time applications. It is based on the template-matching and appearance-based method. At first, we apply Min-max normalization with histogram equalization to the input image according to the variation of intensity. By applying the PCA transform to both the input image and template, PC components are obtained and they are applied to the LDA transform. Then, we estimate the distances between the input image and template, and we select one region which has the smallest distance. SVM is used for final decision whether the candidate face region is a real face or not. Since we detect a face region not the full region but within the $\pm$12 search window, our method shows a good speed and detection rate. Through the experiments with 6 category input videos, our algorithm shows the better performance than the existing methods that use only the PCA transform. and the PCA and LDA transform.

• The KIPS Transactions:PartA
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• v.16A no.5
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• pp.339-346
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• 2009

In order to connect web services, clients generally should use heavy frameworks such as .Net framework and Java run-time environment, which require high performance hardware resources like a personal computer. Therefore, it is impossible for sensor nodes to handle web services due to their limited resources. In this paper, a client agent framework is proposed for dynamically connecting web services in the client node with limited resources. A client agent, which is managed by the framework in other server, has full capability for connecting web services, while a real client has a simple connection module with the client agent. In this framework, a client agent is dynamically generated using the WSDL in the web service server. By using the framework, sensor nodes or mobile devices can enhance their functionalities and services by accessing web services with minimum resources.

• The KIPS Transactions:PartA
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• v.13A no.2 s.99
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• pp.177-184
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• 2006

Since well-known explicit methods for cloth simulation were regarded unstable for large time steps or stiff springs, implicit methods have been proposed to achieve the stability. Large time step makes the simulation fast, and large stiffness enables a less elastic cloth property. Also, there have been efforts to devise so-called semi-implicit methods to achieve the stability and the speed together. In this paper we improve Kang's method (Kang and Cho 2002), and thus devise a scalable method for cloth simulation that varies from an almost explicit to a full implicit method. It is almost as fast as explicit methods and, more importantly, almost as stable as implicit methods allowing large time steps and stiff springs. Furthermore, it has a less artificial damping than the previously proposed semi-implicit methods.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.81-94
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• 2007

The purpose of this study was to critically review biomechanical studies on foot orthoses (FO) in normal and diseased foot and provide beneficial information obtained from researches until now and future researching focus. The search was performed by Medline and Embase database including studies published in English from January 1980 to April 2007. The searching terms were foot orthoses, foot orthotics, insoles and shoe insert. 57 studies including 54 journal articles and 3 abstracts were finally selected under the conditions of having clinical trials, FO, control condition, movement, scientific measuring system. The reviewed studies were divided into 10 categories according to subject characteristics; healthy normal, excessive pronation or flexible flat foot, rheumatoid arthritis, diabetes, medial knee osteoarthritis, forefoot varus, plantar fasciitis, patellofemoral syndrome, cavus foot and finite element model. In summary, first, soft and semirigid FOs with some degree of cushioning showed much higher comfort and efficacy than rigid FO. Second, no big differences between prefabricated and custom FO were shown. Third, the full length's FO was preferable to the half length's FO or simple arch supports. Fourth, the wearing of FO combining medial arch supports and metatarsal dome made positive roles to enhance comfort and functionality and redistribute plantar pressure under the foot. Fifth, for patients with knee-related diseases lateral wedges were preferable. Sixth, measuring systems were properly applied according to the types of foot diseases.

• The Plant Pathology Journal
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• v.33 no.4
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• pp.362-369
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• 2017

White root rot disease, caused by the pathogen Rosellinia necatrix, is one of the world's most devastating plant fungal diseases and affects several commercially important species of fruit trees and crops. Recent global outbreaks of R. necatrix and advances in molecular techniques have both increased interest in this pathogen. However, the lack of information regarding the genomic structure and transcriptome of R. necatrix has been a barrier to the progress of functional genomic research and the control of this harmful pathogen. Here, we identified 10,616 novel full-length transcripts from the filamentous hyphal tissue of R. necatrix (KACC 40445 strain) using PacBio single-molecule sequencing technology. After annotation of the unigene sets, we selected 14 cell cycle-related genes, which are likely either positively or negatively involved in hyphal growth by cell cycle control. The expression of the selected genes was further compared between two strains that displayed different growth rates on nutritional media. Furthermore, we predicted pathogen-related effector genes and cell wall-degrading enzymes from the annotated gene sets. These results provide the most comprehensive transcriptomal resources for R. necatrix, and could facilitate functional genomics and further analyses of this important phytopathogen.