• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.6
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• pp.259-265
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• 2000

The purpose of this paper is to detect and identify topological errors in order to maintain a reliable database for the state estimator. In this paper, a two stage estimation procedure is used to identify the topology errors. At the first stage, the WSAV state estimator which has characteristics to remove bad data during the estimation procedure is run for finding out the suspected branches at which topology errors take place. The resulting residuals are normalized and the measurements with significant normalized residuals are selected. A set of suspected branches is formed based on these selected measurements; if the selected measurement is a line flow, the corresponding branch is suspected; if it is an injection, then all the branches connecting the injection bus to its immediate neighbors are suspected. A new WLAV state estimator adding the branch flow errors in the state vector is developed to identify the branch topology errors. Sample cases of single topology error and topology error with a measurement error are applied to IEEE 14 bus test system.

• ETRI Journal
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• v.33 no.3
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• pp.423-433
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• 2011

This paper introduces an adaptive and integrated utterance verification (UV) framework using minimum verification error (MVE) training as a new set of solutions suitable for real applications. UV is traditionally considered an add-on procedure to automatic speech recognition (ASR) and thus treated separately from the ASR system model design. This traditional two-stage approach often fails to cope with a wide range of variations, such as a new speaker or a new environment which is not matched with the original speaker population or the original acoustic environment that the ASR system is trained on. In this paper, we propose an integrated solution to enhance the overall UV system performance in such real applications. The integration is accomplished by adapting and merging the target model for UV with the acoustic model for ASR based on the common MVE principle at each iteration in the recognition stage. The proposed iterative procedure for UV model adaptation also involves revision of the data segmentation and the decoded hypotheses. Under this new framework, remarkable enhancement in not only recognition performance, but also verification performance has been obtained.

• The Korean Journal of Applied Statistics
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• v.22 no.4
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• pp.723-733
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• 2009

The crucial problems of K-means clustering are deciding the number of clusters and initial centroids of clusters. Hence, the steps of K-means clustering are generally consisted of two-stage clustering procedure. The first stage is to run hierarchical clusters to obtain the number of clusters and cluster centroids and second stage is to run nonhierarchical K-means clustering using the results of first stage. Here we provide automated K-means clustering procedure to be useful to obtain initial centroids of clusters which can also be useful for large data sets, and provide software program implemented using R.

• Archives of Plastic Surgery
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• v.40 no.5
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• pp.553-558
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• 2013

Background Skin-sparing mastectomy with immediate breast reconstruction is increasingly becoming a proven surgical option for early-stage breast cancer patients. Areola-sparing mastectomy (ASM) has also recently become a popular procedure. The purpose of this article is to investigate the reconstructive and aesthetic issues experienced with one-stage nipple and breast reconstruction using ASM. Methods Among the patients who underwent mastectomy between March 2008 and March 2010, 5 women with a low probability of nipple-areolar complex malignant involvement underwent ASM and immediate breast reconstruction with simultaneous nipple reconstruction using the modified C-V flap. The cosmetic outcomes of this series were reviewed by plastic surgeons and patient self-assessment and satisfaction were assessed via telephone interview. Results During the average 11-month follow-up period, there were no cases of cancer recurrence, the aesthetic outcomes were graded as excellent to very good, and all of the patients were satisfied. Two patients developed a gutter-like depression around the reconstructed nipple, and one patient developed skin erosion in a small area of the areola, which healed with conservative dressing. The other complications, such as necrosis of the skin flap or areola, seroma, hematoma, or fat necrosis did not occur. Conclusions Since one-stage nipple and breast reconstruction following ASM is an oncologically safe, cost-effective, and aesthetically satisfactory procedure, it is a good surgical option for early breast cancer patients.

• Archives of Plastic Surgery
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• v.51 no.1
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• pp.118-125
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• 2024

Tamai zone 4 replantation, defined as the replantation at a level proximal to the flexor digitorum superficialis' insertion and distal to where the common digital artery branches into the proper digital artery, has poor functional results because making orthosis and rehabilitation protocols that protect the bone and the flexor and extensor tendons simultaneously difficult. Two cases of Tamai zone 4 replantation are presented: one case of an index finger replantation at the proximal phalanx and a case of ring finger replantation at the proximal interphalangeal joint. The author did not repair the flexor tendon intentionally in the primary replantation and performed two-stage flexor tendon reconstruction later. The total active motions (TAMs) at the last follow-up were 215 and 180 degrees, respectively, with the latter distal interphalangeal joint being an arthrodesis. Both cases had no extension lag in the proximal interphalangeal joint. These results were much better than those in previous reports, in which the mean TAM was 133 degrees or less. The good results appeared to be mainly due to the reasonable and clear postoperative rehabilitation protocols made by the proposed procedure. This procedure may be useful for obtaining reproducible functional results even in Tamai zone 4 replantation.

• Proceedings of the Safety Management and Science Conference
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• 2001.05a
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• pp.77-81
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• 2001

Burn-in is a test procedure to find and eliminate the inherent initial failure of a product during or at the final stage of production process. Software testing is the validation and verification process which is used to cut off the faults from a software. The two have the common function and objective of "debugging". This article summarizes some significant models on the optimal hardware and software burn-in time, and provides the relevant paper lists. The need for the development of the unified burn-in policy of a hardware-software system is addressed.addressed.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.446-450
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• 1987

In this paper, overdetermined method is used for high resolution spectral estimation in case of short data record length. To reduce the computational effort and to obtain recursive form of estimation algorithm, we modify data matrix to have near-Toeplitz structure. Then, new recursive algorithm is derived in the form of fast Kalman algorithm. Two stage procedure is used for the estimation of ARMA parameters. First AR parameters are estimated by using overdetermined modified Yule-walker equation, and then MA parameters are implicitly estimated by estimating numerator spectral coefficients(NS).

• Communications for Statistical Applications and Methods
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• v.7 no.1
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• pp.297-312
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• 2000

A three stage sampling procedure designed to estimate the difference betweentwo normal means is proposed and evaluated within a unified decision-theoretic framework. Both point and fixed-width confidence interval estimation are combined in a single decision rule to make full use of the available data. Adjustments to previous solutions focusing on only one of the latter objectives are indicated. The sensitivity of the confidence interval for detecting shifts in true mean difference is also investigated Numerical and simulation studies are presented to supplement the theoretical results.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.4
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• pp.232-239
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• 1988

The approximate overdetermined method is proposed for high resolution spectral estimation in case of short data record length or narrow band signal. And a new recursive AR parameter estimation is derived in the form of fast algorithm. For ARMA spectral estimation, two stage procedure is used in estimating ARMA parameters. First AR parameters are estimated by using the modified Yule-Walker equations, and then MA parameters are implicitly estimated by estimating numerator spectral(NS) coefficients.

• Korean Management Science Review
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• v.27 no.3
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• pp.15-31
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• 2010

We consider a reverse logistics network design problem for recycling. The problem consists of three stages of transportation. In the first stage products are transported from retrieval centers to disassembly centers. In the second stage disassembled modules are transported from disassembly centers to processing centers. Finally, in the third stage modules are transported from either processing centers or a supplier to a manufacturer, a recycling site, or a disposal site. The objective is to design a network which minimizes the total transportation cost. We design a cooperative coevolutionary algorithm to solve the problem. First, the problem is decomposed into three subproblems each of which corresponds to a stage of transportation. For subproblems 1 and 2, a population of chromosomes is constructed. Each chromosome in the population is coded as a permutation of integers and an algorithm which decodes a chromosome is suggested. For subproblem 3, an heuristic algorithm is utilized. Then, a performance evaluation procedure is suggested which combines the chromosomes from each of two populations and the heuristic algorithm for subproblem 3. An experiment was carried out using test problems. The experiments showed that the cooperative coevolutionary algorithm generally tends to show better performances than the previous genetic algorithm as the problem size gets larger.