• Journal of Communications and Networks
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• v.18 no.5
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• pp.699-712
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• 2016

Recently, greedy algorithm has received much attention as a cost-effective means to reconstruct the sparse signals from compressed measurements. Much of previous work has focused on the investigation of a single candidate to identify the support (index set of nonzero elements) of the sparse signals. Well-known drawback of the greedy approach is that the chosen candidate is often not the optimal solution due to the myopic decision in each iteration. In this paper, we propose a tree search based sparse signal recovery algorithm referred to as the tree search matching pursuit (TSMP). Two key ingredients of the proposed TSMP algorithm to control the computational complexity are the pre-selection to put a restriction on columns of the sensing matrix to be investigated and the tree pruning to eliminate unpromising paths from the search tree. In numerical simulations of Internet of Things (IoT) environments, it is shown that TSMP outperforms conventional schemes by a large margin.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.705-712
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• 2004

In this paper, detection of rotor position at standstill of toroidal switched reluctance motor(TSRM) with built-in search coils using neural network is proposed. When search coils are used as a position sensor, it has many advantages like low cost, decrease in the volume, high robust characteristics and wide applications. However, the initial rotor position detection is very difficult because the search coil's EMF doesn't exist at standstill. In this paper, detection of initial rotor position of TSRM with built-in search coils using neural network is suggested. The experiment for the proposed method are presented. As a result of that, the accuracy and validity of the proposed method is verified.

• Journal of the Korea Society of Computer and Information
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• v.28 no.2
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• pp.1-7
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• 2023

In this paper, we propose a base address candidate selection method using the $gp register and page granularity as a way to build a static analysis environment for firmware based on MIPS architecture. As a way to shorten the base address search time, which is a disadvantage of the base address candidate selection method through inductive reasoning in existing studies, this study proposes a method to perform page-level search based on the $gp register in the existing base address candidate selection method as a reference point for search. Then, based on the proposed method, a base address search tool is implemented and a static analysis environment is constructed to prove the validity of the target tool. The results show that the proposed method is faster than the existing candidate selection method through inductive reasoning.

• The KIPS Transactions:PartD
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• v.11D no.4
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• pp.809-822
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• 2004

In this paper, we propose a concurrency control algorithm based on R-tree for spatial database management system. The previous proposed algorithms can't prevent problem that search operation is to be blocking during update operations. In case of multidimensional indexes like R-tree, locking of update operations may be locked to several nodes, and splitting of nodes have to lock a splitting node for a long time. Therefore search operations have to waiting a long time until update operations unlock. In this paper we propose new algorithms for lock-free search operation. First, we develop a new technique using a linked-list technique on the node. The linked-list enable lock-free search when search operations search a node. Next, we propose a new technique using a version technique. The version technique enable lock-free search on the node that update operations is to be splitting.

• IE interfaces
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• v.15 no.2
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• pp.107-113
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• 2002

Recent reports studied that injuries or deaths frequently occurred in consumer product accidents by product defects. Broadly speaking, product liability is liability which is imposed upon a manufacturer or other seller for personal injury, death, property damage and/or commercial loss arising with respect to a product or service provided by it. In this study, we want to search a method of prevention against appling PL laws. The way was researching on the level of appreciation of PL law, warning messages's means and design criteria for seller or consumer of child toys. As a result, most people didn't understand PL laws. Although they read them before purchasing child toy, many consumers didn't differentiate means of "Notice", "Warning", and "Danger" in warning messages. In addition, they considered important factors in warning messages as notice warning, safety mark(UL, etc), age recommendation and color in order. This study will be effective to search a method of prevention against PL laws.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1646_1647
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• 2009

In this paper, Takagi-Sugeno(T-S) fuzzy controller and search method are developed for efficiency optimization of induction motors(IMs). The proposed control scheme consists of efficiency controller and adaptive backstepping controller. A search controller for which information of input of T-S fuzzy controller is included in efficiency controller that uses a direct vector controlled induction motor. A sliding mode observer is designed to estimate rotor flux and an adaptive backstepping controller is used to control of speed of IMs. Simulation results are presented to validate the proposed controller.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.9
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• pp.1442-1447
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• 1990

In this paper we propose the search algorithm of the boundary nodes that defined as the circuit segmentation when CUT is tested by pseudo-exhaustive testing. The algorithm treats the testability values of the nodes in CUT as the population composed of teh raw data, and after examines the level of significance a and then estimate the confidence interval of teh testability values. Thus One can easily searched the c9oundary nodes and PO of sub circuits. The proposed algorithm has been implemented under UNIX OS with C-language, applied to the combinational logic CUT. As a result, it is shown that the pseudo-exhaustive test patterns are least generated when \ulcornerhas 0.786. We confirmed that the rate of test pattern is 1.22%, compared with exhaustive test.

• Computational Structural Engineering
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• v.23 no.1
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• pp.49-55
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• 2010

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.7 s.361
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• pp.81-89
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• 2007

The Viterbi decoder, which employs the maximum likelihood decoding method, is a critical component in forward error correction for digital communication system. However, lowering power consumption on the Viterbi decoder is a difficult task since the number of paths calculated equals the number of distinctive states of the decoder and the Viterbi decoder utilizes trace-back method. In this paper, we propose a method which minimizes the number of operations performed on the comparator, deployed in the SPEC-T Viterbi decoder implementation. The proposed comparator was applied to the ACSU(Add-Compare-Select Unit) and MPMSU(Minimum Path Metric Search Unit) modules on the decoder. The proposed ACS scheme and MPMS scheme shows reduced power consumption by 10.7% and 11.5% each, compared to the conventional schemes. When compared to the SPEC-T schemes, the proposed ACS and MPMS schemes show 6% and 1.5% less power consumption. In both of the above experiments, the threshold value of 26 was applied.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.9-16
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• 2021

Due to the prolonged infectious disease of COVID-19 worldwide, there are various security threats due to network attacks on Internet of Things devices that are vulnerable to telecommuting. Initially, users of Internet of Things devices were exploited for vulnerabilities in Remote Desktop Protocol, spear phishing and APT attacks. Since then, the technology of network attacks has gradually evolved, exploiting the simple service discovery protocol of Internet of Things devices, and DRDoS attacks have continued to increase. Existing SSDPs are accessible to unauthorized devices on the network, resulting in problems with information disclosure and amplification attacks on SSDP servers. To compensate for the problem with the authentication procedure of existing SSDPs, we propose a hash-based SSDP that encrypts server-specific information with hash and adds authentication fields to both Notify and M-Search message packets to determine whether an authorized IoT device is present.