• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.46 no.6
• /
• pp.1-8
• /
• 2009

Detecting entry and exit zones in a view covered by multiple cameras is an essential step to determine the topology of the camera setup, which is critical for achieving and sustaining the accuracy and efficiency of multi-camera surveillance system. In this paper, a graph theoretic clustering method is proposed to detect zones using data points which correspond to entry and exit events of objects in the camera view. The minimum spanning tree (MST) is constructed by associating the data points. Then a set of well-formed clusters is sought by removing inconsistent edges of the MST, based on the concepts of the cluster balance and the cluster density defined in the paper. Experimental results suggest that the proposed method is effective, even for sparsely elongated clusters which could be problematic for expectation-maximization (EM). In addition, comparing to the EM-based approaches, the number of data required to obtain stable outcome is relatively small, hence shorter learning period.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.426-430
• /
• 2005

The computer practicing class advances to reach the ultimate goal of learning through the comprehensive learning of theory. Moreover, the improved function and environment of computer makes it easy for students to access a variety of information. However, students are likely to get into the internet and other things mainly for fun during the computer practicing class, and the multi-tasking may distract the concentration of students and degrade their performance. Computers for practice purpose need to be controlled to minimize such distraction. In this dissertation, we monitor and control computers which are used by students for the purpose of practicing, realize the function of transfer and deletion of file, whole shutdown of computer and screen capture. We also applied the class based on current way and realized program, and assigned the practice work on the basis of what was learned during the class. We intend to understand the relation between the concentration of students and their performance by assigning practice work related to survey after the class, capture file and log file

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.2
• /
• pp.640-645
• /
• 2011

The purpose of this article is to investigate ways of making the cloze test more valid as an English proficiency test so that it can provide a better format for the cloze test especially to the non-native teachers in EFL environments. This investigation identifies ways of validity in terms of materials, deletion rates, item characteristics and scoring methods used in cloze tests. An increase in test validity can be accomplished by knowing how the four factors affect the cloze test results and how to manipulate them. Practical suggestions are provided for teachers to design a cloze test. Teachers can develop the reliability and validity of cloze tests by manipulating the four factors. In seeking a more valid and reliable cloze format, this research gives some suggestions based on a literature review. We can conclude that a cloze test can be valid only when teachers are aware of the factors which affect the test result and the ways to handle the factors to make the test appropriate for their test purposes.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.2
• /
• pp.8-15
• /
• 2018

Hollow Core Slab is a very efficient system that can reduce weight and its use has increased. Void slab is a concrete slab that has voids substituted with void material. Because of its saved volume of concrete, void slab can reduce weight of slabs. Also, it can't only save concrete but also can reduce carbon-emission. However, because of the unclear bearing strength at the part of void substituted with voiding material, several problems occur in constructing field. In this study, void slab including void material was built and local bearing strength test was carried out for 3 types of load(truck load, support load and Jack support load). As a result, bearing strength of void neck and upper void material is more than allowable load. And also, bearing strength of specimens with using deck and not using deck are also over allowable loads.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.9
• /
• pp.898-903
• /
• 2010

Popularity of smartphones such as Google Android phones and Apple iphones, is increasing the demand on more reliable high performance file system for flash memory. In this paper, we propose two techniques to improve the performance of YAFFS (Yet Another Flash File System), while enhancing the reliability of the system. Specifically, we first propose to manage metadata and user data separately on segregated blocks and indexing information piggy-back technique for reducing mount time and also enhancing performance. Second, we tailor the wear-leveling to the segregated metadata and user data blocks. Performance evaluation results based on real hardware system with 1GB NAND flash memory show that the YAFFS with our proposed techniques realized outperforms the original YAFFS by six times in terms of mount speed and five times in terms of benchmark performance, while reducing the average erase count of blocks by 14%.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.12
• /
• pp.2241-2248
• /
• 2007

This paper proposes the web-based virtual collaboration among experts. The proposed system supports the presentation tool using Synchronous Multimedia Integration Language(SMIL) which is the easy and efficient way of adding multimedia to presentations. The presentation gives essential information to the participants before actual discuss. The participants use texts in discussing over the presented medical image. The spatial elements such as point or line, and some type of marker with their relative participants' comments can be set or removed dynamically to represent areas of interest in digital images. XML files are used for recording experts' opinions as well as the spatial elements that are associated with digital images during the discussion and stored for future reference. The participants can also set and reset a polygon in the image to select the interested area and refer to the stored relating information.

• Journal of Korea Society of Industrial Information Systems
• /
• v.24 no.2
• /
• pp.1-14
• /
• 2019

Since most documents used in web, XML, office applications are tree-structured, diff, merge, and version control for tree-structured documents in multi-user environments are crucial tasks. However research on edit scripts which is a basis for them is in primitive stage. In this paper, we present a document model for understanding the change of tree-structured documents as edit scripts are executed, and propose a method of switching adjacent edit operations on tree-structured documents based on the analysis of the effects of edit operations. Mostly, edit scripts which are produced as the results of diff on tree-structured documents only consist of basic operations such as update, insert, delete. However, when move and copy are included in edit scripts, because of the characteristics of their complex operation, it is often that edit scripts are generated to execute in two passes. In this paper, using the proposed method of switching edit operations, we present an algorithm of transforming the edit scripts of X-treeESgen, which are designed to execute in two passes, into the ones that can be executed in one pass.

• Journal of Broadcast Engineering
• /
• v.23 no.6
• /
• pp.886-895
• /
• 2018

In this paper, we introduce a technique to detect the video forgery by using the regularity that occurs in the video compression process. The proposed method uses the hierarchical regularity lost by the video double compression and the frame deletion. In order to extract such irregularities, the depth information of CU and TU, which are basic units of HEVC, is used. For improving performance, we make a depth map of CU and TU using local information, and then create input data by grouping them in GoP units. We made a decision whether or not the video is double-compressed and forged by using a general three-dimensional convolutional neural network. Experimental results show that it is more effective to detect whether or not the video is forged compared with the results using the existing machine learning algorithm.

• Journal of the Korea Computer Graphics Society
• /
• v.25 no.1
• /
• pp.13-22
• /
• 2019

In this paper, we propose a new method to improve the details of the fluid surface by removing liquid sheets that are over-preserved in particle-based water simulation. A variety of anisotropic approaches have been proposed to address the surface noise problem, one of the chronic problems in particle-based fluid simulation. However, a method of stably expressing the preservation and breakup of the liquid sheet has not been proposed. We propose a new framework that can dynamically add and remove the water particles based on anisotropic kernel and density to simultaneously represent two features of liquid sheet preservation and breakup in particle-based fluid simulations. The proposed technique well represented the characteristics of a fluid sheet that was breakup by removing the excessively preserved liquid sheet in a particle-based fluid simulation approach. As a result, the quality of the liquid sheet was improved without noise.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.19 no.5
• /
• pp.151-166
• /
• 2009

To prove the integrity of digital evidence on the investigation procedure, the data which is using the MD 5(Message Digest 5) hash-function algorithm has to be discarded, if the integrity was damaged on the investigation. Even though a proof restoration of the deleted area is essential for securing the proof regarding a main phase of a case, it was difficult to secure the decisive evidence because of the damaged evidence data due to the difference between the overall hash value and the first value. From this viewpoint, this paper proposes the novel model for the mobile forensic procedure, named as "E-Finder(Evidence Finder)", to ,solve the existing problem. The E-Finder has 5 main phases and 15 procedures. We compared E-Finder with NIST(National Institute of Standards and Technology) and Tata Elxsi Security Group. This paper thus achieved the development and standardization of the investigation methodology for the mobile forensics.