• International journal of advanced smart convergence
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• v.10 no.1
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• pp.142-150
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• 2021

Open-channel SSD is a new type of Solid-State Disk (SSD) that improves the garbage collection overhead and write amplification due to physical constraints of NAND flash memory by exposing the internal structure of the SSD to the host. However, the host-level Flash Translation Layer (FTL) provided for open-channel SSDs in the current Linux kernel consumes host memory excessively because it use page-level mapping table to translate logical address to physical address. Therefore, in this paper, we implemente a selective mapping table loading scheme that loads only a currently required part of the mapping table to the mapping table cache from SSD instead of entire mapping table. In addition, to increase the hit ratio of the mapping table cache, filesystem information and mapping table access history are utilized for cache replacement policy. The proposed scheme is implemented in the host-level FTL of the Linux kernel and evaluated using open-channel SSD emulator. According to the evaluation results, we can achieve 80% of I/O performance using the only 32% of memory usage compared to the previous host-level FTL.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.723-728
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• 2004

Recently, because of the extensive use of geographic information in the various fields, the requirement for the easy circulation and utilization of the various geographic information among the individuals, organizations, societies and countries is raised. In order to support the interoperability of the heterogeneous geographic information in the various fields, OGC(Open GIS Consortium) proposed the GML(Geography Markup Language) specification that defines the XML encoding rule about the heterogeneous geographic information. In addition, ISO/TC 211 adopted the GML specification to make it as the international standard. Therefore, in this paper, we first analyzed the GML 3.0 specification in detail that can support the interoperability of the heterogeneous geographic information. And then we suggested and applied the mapping rule that define the encoding method to improve the encoding process easily and efficiently. Finally, we designed and implemented the GML 3.0 encoding system using the mapping rule to encode the geographic information that was constructed in spatial databases into the GML 3.0 document. Especially, we used ZEUS as a spatial database system to test our encoding system in this paper.

• Journal of Intelligence and Information Systems
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• v.12 no.2
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• pp.33-48
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• 2006

The Semantic Web and its related technologies have been opening the era of information sharing via the Web. There are, however, several huddles still to overcome in the new era, and one of the major huddles is the issue of information integration, unless a single unified and huge ontology could be built and used which could address everything in the world. Particularly in the e-business area, the problem of information integration is of a great concern for product search and comparison at various Internet shopping sites and e-marketplaces. To overcome this problem, we proposed an ontology-driven mapping algorithm between heterogeneous product classification and description frameworks. We also peformed a comparative evaluation of the proposed mapping algorithm against a well-Down ontology mapping tool, PROMPT.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.56-76
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• 2022

This study shared with community mapping participants spatial analysis information, collected using smart devices, to give them an opportunity to objectively review their opinions. The study examined the impact of sharing such spatial information on residents' decision-making and perceptions. Yeongju-dong in Jung-gu district of Busan Metropolitan City, South Korea was selected for the case study; community mapping was carried out in Yeongju-dong to identify hazardous areas to improve pedestrian safety of primary school students. The community mapping participants drew a preliminary hazard map based on their experience and perception. Then, they drew a second hazard map after being given spatial information on pedestrian safety installations and pedestrian flow collected with smart devices including drones and sensors. Numerous changes in ranking across various sections occurred when the two maps were compared. There was a climb in the ranking of areas where the pedestrian flow was higher and lacked safety installations based on objective measurements over the perceptions of the participating people. Furthermore, according to a survey conducted among the participants, the provision of spatial analysis information using smart devices during community mapping process not only helped them recognize local community problems, but also raised their expectations that their submitted opinions would be reflected in policies. Moreover, the participants demonstrated increased self-confidence and faith in themselves as they were able to have more trust in the outcome they created.

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.4
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• pp.209-215
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• 2009

Reconfigurable array architecture is recently attracting much attention. It is a flexible hardware architecture, which can dynamically change its configuration to execute various functions while maintainning high performance. However, pursuing flexibility and performance at the same time leads to complexity, thereby makes the mapping of applications a difficult process. There have been attempts to use compiler or high level synthesis techniques to solve the problem. In this paper, we propose yet another method, which uses libraries for the mapping to provide an abstracttion of the internal structure and at the same time to reduce the development time and efforts through the automated process. We have selected a JPEG decoder as an example to apply the proposed method. As a result, we obtained about 20% less performance compared to manual mapping but development time is dramatically reduced to less than 1%.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.705-708
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• 2005

Mobile Mapping Systems using the vehicle equipped the GPS, IMU, CCD Cameras is the effective system for the management of the road facilities, update of the digital map, and etc. They must provide users with the sensor data which is acquired by Mobile Mapping Systems in real-time so that users can process what they want by using the latest data. But it' s not an easy process because the amount of sensor data is very large, particularly image data to be transmitted. So it is necessary to reduce the amount of image data so that it is transmitted effectively. In this study, the effective method was suggested for the compression/decompression image data using the Wavelet Transformation and Huffman Coding. This technique will be possible to transmit of the geographic information effectively such as position data, attitude data, and image data acquired by Mobile Mapping Systems in the wireless internet environment when data is transmitted in real-time.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.851-852
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• 2008

In this paper, we propose a tone mapping method using Non-linear Dynamic Range Normalization (NDRN) for High Dynamic Range (HDR) images. HDR images are not suitable for commercial display devices because dynamic range of HDR images do not match with one of Low Dynamic Range (LDR) display devices. To reproduce a tone of HDR images for LDR displays, tone mapping methods have been proposed such as local and global tone mapping. We introduce NDRN to locate mean of HDR images at the center of LDR. NDRN preserves the details for highlight and shadow. By suppressing the significant luminance change in tone mapping, naturalness of original image can be also preserved. The experimental results show that the proposed method preserves details and naturalness of original images.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1165-1168
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• 2003

In this paper, a CLB-based CPLD low-power technology mapping algorithm is proposed. To perform low power technology mapping for CPLD, a given Boolean network have to be represented to DAG. The proposed algorithm are consist of three step. In the first step, TD(Transition Density) calculation have to be performed. In the second step, the feasible clusters are generated by considering the following conditions: the number of output, the number of input and the number of OR-terms for CLB(Common Logic Block) within a CPLD. The common node cluster merging method, the node separation method, and the node duplication method are used to produce the feasible clusters. In the final step, low power technology mapping based on the CLBs is packing the feasible clusters into the several proper CLBs. Therefore the proposed algorithm is proved an efficient algorithm for a low power CPLD technology mapping.

• Journal of applied mathematics & informatics
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• v.20 no.1_2
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• pp.465-478
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• 2006

In this paper, we introduce a new class of completely generalized strongly nonlinear quasivariational inequalities and establish its equivalence with a class of fixed point problems by using the resolvent operator technique. Utilizing this equivalence, we develop a three-step iterative scheme with errors, obtain a few existence theorems of solutions for the completely generalized non-linear strongly quasivariational inequality involving relaxed monotone, relaxed Lipschitz, strongly monotone and generalized pseudocontractive mappings and prove some convergence and stability results of the sequence generated by the three-step iterative scheme with errors. Our results include several previously known results as special cases.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.405-405
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• 2000

We designed the artificial olfactory sensing system (Electronic Nose) using MOS type sensor array fur recognizing and analyzing odour. The response of individual sensors of sensor array, each processing a slightly different response towards the sample volatiles, can provide enough information to discriminate between sample odours. In this paper, we applied clustering algorithm for dimension reduction, such as linear projection mapping (PCA method), nonlinear mapping (Sammon mapping method) and the combination of PCA and Sammon mapping having a better discriminating ability. The odours used are VOC (Volatile chemical compound) and Toxic gases.