• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.5
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• pp.24-30
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• 1996

In this paper, we propose a fast code acquisition method that can reduce drastically the mean acquisition time of the direct sequence spread spectrum (DS-SS) system by using and integrated search and verification (ISV) scheme. The proposed method performs simultaneously the search and verification processes at every search cell, through storing sufficiently long signal samples enough to perform the verification process form the previously received samples. We analyze and acquisition performance in the case of Gaussian channel to evaluate theacquisition perfomrance of the proposed method. From the simple numericl analysis result, we have shown that the acquisition performance of the proposed method is better than that of the conventional serial search method, and the performance improvement becomes more prominent as the channel environment becomes degraded.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.10
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• pp.595-602
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• 2003

This Paper presents an efficient hybrid techniques for a standard cell placement. The prototype tool adopts a middle-down methodology in which an n${\times}$m grid is imposed over the layout area and cells are assigned to bins forming a global placement. The optimization technique applied in this phase is based on the Relaxation-Based Local Search (RBLS) framework [12］in which a combinatorial search mechanism is driven by an analytical engine. This enables a more global view of the problem and results in complex modifications of the placement in a single search“move.”Details of this approach including a novel placement legalization procedure are presented. When a global placement converges, a detailed placement is formed and further optimized by the optimal interleaving technique[13］. Experimental results on MCNC benchmarking circuits are presented and compared with the Feng Shui's results in［14］. Solution Qualifies are almost the same as the Feng Shui's results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.1A
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• pp.65-76
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• 2004

In this paper, a novel preamble structure, including a synchronization preamble and a cell search preamble, is proposed for OFDM-based cellular systems. An efficient algorithm for downlink synchronization and cell searching using the preamble is also proposed. The synchronization process includes the initial symbol timing estimation using continuously, or at least, periodically transmitted downlink signal, frame synchronization, the fine symbol timing estimation, and the frequency offset estimation using the synchronization preamble, and the cell identification using the cell searching preamble. Performance of each synchronization and cell searching step is analyzed and the analytic results including the overall performance of the synchronization and cell searching are verified by computer simulation. It is shown that the proposed preamble with the corresponding synchronization and cell searching algorithm can provide very robust synchronization and cell searching capability even in bad cellular environments.

• Journal of Communications and Networks
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• v.2 no.1
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• pp.58-68
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• 2000

In this paper we introduce the correlation-aided distributed sample acquisition (CDSA) scheme for fast cell search in IMT-2000 W-CDMA cellular system. The proposed scheme incorporates the state symbol correlation process into the comparison-correction based synchronization process of the original DSA scheme to enable fast acquisition even under very poor channel environment. for its realization, each mobile station (MS) has to store in its memory a set of state sample sequences. which are determined by the long-period scrambling sequences used in the system and the sampling interval of the state samples. CDSA based cell search is carried out in two stages : First, the MS first acquires the slot timing by using the primary synch code (PSC) and then identifies the igniter code which conveys the state samples of the current cell . Secondly. the MS identifies the scrambling code and frame timing by taking the comparison-correction based synchronization approach and, if the identification is not done satisfactorily within preset time. it initiates the state symbol correlation process which correlates the received symbol sequence with the pre-stored state sample sequences for a successful identification. As the state symbol SNR is relatively high. the state symbol correlation process enables reliable synchronization even in very low chip-SNR environment. Simulation results show that the proposed CDSA scheme outperforms the 3GPP 3-step approach, requiring the signal power of about 7 dB less for achieving the same acquisition time performance in low-SNR environments. Furthermore, it turns out very robust in the typical synchronization environment where large frequency offset exists.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1309-1314
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• 2007

The assignment of cells to reporting or non-reporting cells is an NP-hard problem having an exponential complexity in the Reporting Cell Location Management (RCLM) system. Frequent location update may result in degradation of quality of service due to interference. Miss on the location of a mobile terminal will necessitate a search operation on the network when a call comes in. The number of reporting cells and which cell must be reporting cell should be determined to balance the registration (location update) and search (paging) operations to minimize the cost of RCLM system. T1is paper compares Max-Min ant system (MMAS), rank-based ant system (RAS) and hybrid method of MMAS and RAS that generally used to solve combinatorial optimization problems. Experimental results demonstrate that hybrid method of MMAS and RAS is an effective and competitive approach in fairly satisfactory results with respect to solution quality and execution time for the optimal design of location management system.

• Biomedical Science Letters
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• v.12 no.3
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• pp.139-143
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• 2006

Jopock (Jpk) has previously been ascertained that induces both bacterial and mammalian cell death. The Escherichia coli cells expressing Glutathion S-transferase (GST) fused Jpk showed elongated phenotype and inhibited cell growth which led eventual cell death. In an attempt to search the genetic suppressor of the lethal protein Jpk in bacterial cells, we constructed a unidirectional protein expression vector inserting tac promoter next to the C-terminus Jpk in pGEX-Jpk. The function of additional tac promoter was confirmed by substituting lac promoter in Plac-TOPO plasmid. The cells harboring plac- TOPO, which regulates $lacZ{\alpha}$ gene expression under lac promoter, formed blue colonies in 5-bromo-4-3 $indolyo-{\beta}-D-galactoside$ (X-gal) plate. When lac promoter was changed to tac promoter, same results were observed. Since the addition of tac promoter did not affect the toxic effect of Jpk, the pGEX-Jpk-ptac could be a useful vector for the screening of suppressor(s) for Jpk, in which GST-Jpk and a putative Jpk-suppressing protein are coexpressing from two unidirectional tac promoters, which response to the same inducer, $isopropyl-{\beta}-D-thiogalactopyranoside (IPTG)$.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4997-4999
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• 2015

Advanced oral squamous cell carcinoma (SCC) is a possible risk factor for myiasis, a parasitic infestation of vital tissue of humans or other mammals by dipterous larvae (maggots). Oral myiasis is a rare entity, and is mostly associated with various medical and anatomical conditions, such as neglected mandibular fracture, lip incompetence, cerebral palsy, poor oral hygiene, suppurative lesions, and cancerous wounds. Larvae cause itching and irritation due to their crawling movements and can destroy vital tissues, inducing serious or even life-threating hemorrhage. The aim of the present article was to highlight the occurrence of oral myiasis in association with squamous cell carcinoma and also to highlight the treatment and preventive approaches for such cases. A literature search was performed using MEDLINE for articles published in English relating to the occurrence of oral myiasis in oral SCC. Our search revealed 6 reports on myiasis associated with oral SCC. The surgical debridement of infected tissue with the removal of maggots is the treatment of choice in most cases of oral myiasis.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.386-386
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• 2000

Cell mapping is a powerful computational technique for analyzing the global behavior of nonlinear dynamic systems. It simplifies the task of analyzing a continuous phase space by partitioning it into a finite number of disjoint cells and approximating system trajectories as cell transitions. A cell map for the system is then constructed based on the allowable control actions. Next search algorithms are employed to identify the optimal or near-optimal sequence(s) of control actions required to drive the system from each cell to the target cell by an "unravelling algorithm." Errors resulting from the cell center-point approximation could be reduced and eliminated by fuzzifying the bonders of cells. The dynamic system control method based on the cell mapping has been demonstrated for a motor control problem.l problem.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.2
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• pp.155-164
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• 2000

Recently Fiber-optic Micro-cellular Wireless Network is considered to solve frequent handoffs and local traffic unbalance in microcellular systems. In this system, central station which is connected to several microcells by optical fiber manages the channels. We propose an efficient sectorization algorithm which dynamically clusters the microcells to minimize the blocked and handoff calls and to balance the traffic loads in each cell. The problem is formulated as an integer linear programming. The objective is to minimize the blocked and handoff calls. To solve this real time sectorization problem the Tabu Search is considered. In the tabu search intensification by Swap and Delete-then-Add (DTA) moves is implemented by short-term memory embodied by two tabu lists. Diversification is considered to investigate proper microcells to change their sectors. Computational results show that the proposed algorithm is highly effective. The solution is almost near the optimal solution and the computation time of the search is considerably reduced compared to the optimal procedure.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.1
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• pp.217-222
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• 2014

In this paper, I propose an efficient data search system using data partitioning algorithm in Microsoft Excel. I propose searching algorithm to retrieve data quickly using VBA functioning in the Excel. This algorithm is to specify the sheet you are looking for. Once the sheet is specified, the algorithm searches the beginning and the end of the data in the sheet. The algorithm compares intermediate values and key words, from the starting position of the cell. In this way, it will search data to the end. This proposed algorithm was implemented and tested in the Excel system using VBA program. The experimental results showed that the performance was better than that of the conventional sequential search method.