• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.15-27
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• 2023

The incidence of melioidosis cases caused by the gram-negative pathogen Burkholderia pseudomallei (BP) is seeing an increasing trend that has spread beyond its previously known endemic regions. Biofilms produced by BP have been associated with antimicrobial therapy limitation and relapse melioidosis, thus making it urgently necessary to understand the mechanisms of biofilm formation and their role in BP biology. Microbial cells aggregate and enclose within a self-produced matrix of extracellular polymeric substances (EPSs) to form biofilm. The transition mechanism of bacterial cells from planktonic state to initiate biofilm formation, which involves the formation of surface attachment microcolonies and the maturation of the biofilm matrix, is a dynamic and complex process. Despite the emerging findings on the biofilm formation process, systemic knowledge on the molecular mechanisms of biofilm formation in BP remains fractured. This review provides insights into the signaling systems, matrix composition, and the biosynthesis regulation of EPSs (exopolysaccharide, eDNA and proteins) that facilitate the formation of biofilms in order to present an overview of our current knowledge and the questions that remain regarding BP biofilms.

• Journal of Power Electronics
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• 제9권6호
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• pp.949-959
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• 2009

This paper presents a systematic investigation of the fault-mode behaviors of matrix converter systems. Knowledge about converter behaviors after fault occurrence is important from the standpoint of reliable system design, protection and fault-tolerant control. Converter behaviors have been, in detail, examined with both qualitative and quantitative approaches for key fault types, such as switch open-circuited faults and switch short-circuited faults. Investigating the fault-mode behaviors of matrix converters reveals that converter operation with switch short-circuited faults leads to overvoltage stresses as well as overcurrent stresses on other healthy switching components. On the other hand, switch open-circuited faults only result in overvoltage to other switching components. This study can be used to predict fault-mode converter behaviors and determine additional stresses on remaining power circuit components under fault-mode operations.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.795-802
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• 2001

The commutation and control in matrix converters is more complicated as in voltage source converters. Natural freewheeling paths do not exist and the theoretic absent storage elements result in a direct coupled system of load and line currents as well as voltages. The paper offers an overview about staggered commutation and control policies in matrix converters. Based on the knowledge about load current direction and the signs of the line to line input voltages different multi-step commutation policies were derived. This paper examines the application of that policies in the case of space vector modulation and direct control methods with the focus on the resulting effects to the reference output voltage deviation.

• Journal of Power Electronics
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• 제3권1호
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• pp.24-32
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• 2003

The commutation and control in matrix converters is more complicated as in voltage source converters. Natural freewheeling paths do not exist and the theoretic absent storage elements result in a direct coupled system of load and line currents as well as voltages. The paper offers an overview about staggered commutation and control policies in matrix converters. Based on the knowledge about load current direction and the signs of the line to line input voltages different multi-step commutation policies were derived. This paper examines the application of that policies in the case of space vector modulation and direct control methods with the focus on the resulting effects to the reference output voltage deviation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.237-240
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• 1989

This paper deals with the expert system for power system recognition of energized and deenergized system using circuit breaker information. The basic idea is isolating the system with the system matrix representing the system configuration and the states of the circuit breakers. The knowledge base is composed of these isolated systems and decision rules. The isolated system with the sources is recognized as the energized system and the system without the source as the deenergized system. The rules use the system matrix and the the inference scheme is simplified in a great deal. Above all, the overall searching labor of the rules is independent on the system size and it is possible to expand into the real system and the real time restoration can be carried out easily. The expert system is written in PROLOG.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.734-736
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• 1996

This paper presents a method of calculating a selective number of eigenvalues in power systems, which are rightmost, or are largest modulus. The modified Arnoldi method in conjunction with implicit shift OR-algorithm is used to calculate the rightmost eigenvalues. Algorithm requires neither a prior knowledge of the specified shifts nor the calculation of inverse matrix. The key advantage of the algorithm is its ability to converge to the wanted eigenvalues at once. The method is compared with the modified Arnoldi method combined with S-matrix transformation, where the eigenvalues having the largest modulus are to be determined. The two methods are applied to the reduced Kansai system. Convergence characteristics and performances are compared. Results show that both methods are robust and has good convergence properties. However, the implicit shift OR method is seen to be faster than the S-matrix method under the same condition.

• 경영과학
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• 제24권2호
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• pp.177-196
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• 2007

For better predictions and classifications in customer recommendation, this study proposes an integrative model that efficiently combines the currently-in-use statistical and artificial intelligence models. In particular, by integrating the models such as Association Rule, Frequency Matrix, and Rule Induction, this study suggests an integrative prediction model. Integrated models consist of four models: ASFM model which combines Association Rule(A) and Frequency Matrix(B), ASRI model which combines Association Rule(A) and Rule Induction(C), FMRI model which combines Frequency Matrix(B) and Rule Induction(C), and ASFMRI model which combines Association Rule(A), Frequency Matrix(B), and Rule Induction(C). The data set for the tests is collected from a convenience store G, which is the number one in its brand in S. Korea. This data set contains sales information on customer transactions from September 1, 2005 to December 7, 2005. About 1,000 transactions are selected for a specific item. Using this data set. it suggests an integrated model predicting whether a customer buys or not buys a specific product for target marketing strategy. The performance of integrated model is compared with that of other models. The results from the experiments show that the performance of integrated model is superior to that of all other models such as Association Rule, Frequency Matrix, and Rule Induction.

• 대한수학회보
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• 제47권1호
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• pp.63-71
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• 2010

In this paper, we analyze a zero-knowledge identification scheme presented in [1], which is based on an average-case hard problem, called distributional matrix representability problem. On the contrary to the soundness property claimed in [1], we show that a simple impersonation attack is feasible.

• 중환자간호학회지
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• 제12권1호
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• pp.71-81
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• 2019

Purpose : The purpose of this study was to assess hospital nurses' knowledge, importance and performance in keeping nursing records. Methods: The research design was a descriptive study. The sample for this study was 186 nurses with at least one year of work experience at a hospital with more than 800 beds in Seoul. Knowledge was self-reported using the Nurse Charting Knowledge Scale. Importance and performance were rated on a 4-point scale of 26 items. Data were analyzed by SPSS 21.0 program and IPA. Results: This study showed significant results that knowledge, importance and performance for keeping record are related to each other. The importance and performance of nurse's records were relatively higher than the mean. In the IPA Matrix, there were 2 items requiring improvement, 13 items requiring maintenance, and 11 items with low priority. Conclusion: Therefore, awareness of the importance of record keeping and continuous education on nursing record knowledge should be provided so that nurses can improve their record keeping skills.

• 지식경영연구
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• 제6권2호
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• pp.1-22
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• 2005

Knowledge is recognized as the most important asset among enterprises. Therefore, the necessity of knowledge management is ever on the increase nowadays. While many people have endeavored to develop knowledge storage, sharing and usage, knowledge creation is not sufficiently investigated for practical application, because knowledge creation is largely related to creativity and difficult to establish a systematic methodology. In order to overcome such problems, the creative knowledge creation model is proposed by using the whole brain theory and creative thinking tools. First of all, the creative knowledge creation model is based on the Nonaka's knowledge creation model integrated with the whole brain theory. The whole brain theory is then used as a standard to organize a whole brain team that is composed of members who have diverse thinking patterns. For creative thinking tools, the mandal-art and the contradiction matrix of TRIZ are used for a knowledge conversion. Each process of the creative knowledge creation model is sequentially suggested and several terms are defined. In order to verify the effectiveness of the creative knowledge creation model, the proposed model is applied to the development of a dishwasher with a new concept. According to the order of the proposed method, the model is applied twice in the cycle of spiral evolution. Three kinds of dish-washing methods have been developed using the proposed model. The results of the application are then analyzed and presented.