• Journal of Power Electronics
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• v.16 no.2
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• pp.447-454
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• 2016

A single-ended primary-inductor converter (SEPIC) features low input current ripple and output voltage up/down capability. However, the switching devices in a two-level SEPIC suffer from high voltage stresses and switching losses. To cope with this drawback, this study proposes a three-level SEPIC that uses a low voltage-rated switch and thus achieves better switching performance compared with the two-level SEPIC. The three-level SEPIC can reduce switch voltage stresses and switching losses. The converter operation and control method are described in this work. The experimental results for a 500 W prototype converter are also discussed. Experimental results show that unlike the two-level SEPIC, the three-level SEPIC achieves improved power efficiency with balanced capacitor voltages.

• Asia pacific journal of information systems
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• v.20 no.1
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• pp.33-56
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• 2010

The current business environment has been characterized as less munificent, highly uncertain and constantly evolving. In this environment, the company with dynamic capability is reported to be more successful than others in building competitive advantage. Dynamic capability focuses on the link between a dynamically changing environment, strategic agility, architectural reconfiguration, and value creation. Being characterized to be flexible and adaptive to market circumstance changes, an organization with dynamic capability is described to have high resource fluidity, which represents business process, resource allocation, human resource management and incentives that make business transformation faster and easier. Successful redeployment of the resources for dynamic adaptation requires organizational forms and reward systems to be well aligned with firm's technological infrastructures and business process. The alignment is considered to be an executive level commitment. Building dynamic capability is knowledge driven; relying on new knowledge to reconfigure firm's resources. Past studies established the link between the effective execution of a knowledge-focused strategy and relevant setting of architectural elements such as human resources, structure, process and information systems. They do not, however, describe in detail the underlying processes by which architectural elements are adjusted in coordinated manners to build knowledge-driven dynamic capability. In fact, understandings of these processes are one of the top issues in IT management. This study analyzed how a Korean corporation with a knowledge-focused strategy aligned its architectural elements to develop the dynamic capability and thus create value in the dynamically changing markets. When the Korean economy was in crisis, the company implemented a knowledge-focused strategy, restructured the organization's architecture by which human and knowledge resources are identified, structured, integrated and coordinated to identify and seize market opportunity. Specifically, the following architectural elements were reconfigured: human resource, decision rights, reward and evaluation systems, process, and IT infrastructure. As indicated by sales growth, the reconfiguration helped the company create value under an extremely turbulent environment. According to Ancona et al. (2001), depending on the types of lenses the organization uses, different types of architecture will emerge. For example, if an organization uses political lenses focusing on power, influence, and conflict. the architecture that leverage power and negotiate across multiple interest groups would emerge. Similarly, if an organization uses economic lenses focusing on the rational behavior of organizational actors making choices based on the costs and benefits of action, organizational architecture should be designed to motivate and provide incentives for the actors (Smith, 2001). Compared to this view, information processing perspectives consider architecture to be designed to maximize the capacity of information processing by the actors. Using knowledge lenses, the company studied in this research established architectural elements in a manner that allows the firm to effectively structure knowledge resources to form dynamic capability. This study is revelatory single case with a historic perspective. As a result of this study, a set of propositions and a framework are derived, which can be used for architectural alignment.

• Communications of Mathematical Education
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• v.22 no.3
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• pp.369-382
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• 2008

We discuss the effect of ability grouping calculus courses based upon student's proficiency of the subject and their collective examination of midterms and finals among mid-level and low-level classes. We assess incoming freshmen at Seoul National University of Technology(SNUT) of their proficiency in calculus and assign them to the appropriate levels within the course(i.e., high-level, mid-level, low-level). We found that this was beneficial to both students and instructors. Instructors can easily determine the pace in which each class should be kept, and students can quickly adapt to the learning environment.

• Journal of Korean Society for Quality Management
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• v.52 no.2
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• pp.357-376
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• 2024

Purpose: The purpose of this study is to design an objective and comparable diagnostic system for diagnosing the technology level of military maintenance depots and verify its actual applicability. Methods: Literature Review, Capability Maturity Model Integration, Analytic Hierarchy Process. Results: Military maintenance depot maintenance quality level diagnosis items, Maintenance quality level by maintenance technology area, Guidelines for diagnosing maintenance quality level, Quality level comparison results by area and implications for improvement. Conclusion: In order to systematically evaluate the maintenance quality of military maintenance depots, this study was conducted with the goal of designing an overall maintenance quality diagnosis system, including diagnosis areas, diagnosis items, and a diagnosis score award system, by improving the existing evaluation method. In addition, the newly developed maintenance quality diagnosis system was applied to actual evaluation activities and the results were returned to members, confirming the usefulness of the developed maintenance quality diagnosis system in the field.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.10
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• pp.73-80
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• 1995

In this paper, a synthesis tool using matrix operations for designing multi-level Reed Muller circuits is described which has been named as MRM (Multi-level Reed Muller Minimizer). The synthesis method which uses matrix operations has advantages in effectively minimizing chip area, delay optimization and fault detection capability. However, it uses only truth-table type maps for inputs, synthesizing only small circuits. To overcome the weakness, our method accepts two-level description of a logic function. Since the number of cubes in the two-level description is small, the input matrix becomes small and large circuits can be synthesized. To convert two-level representations into multi-level ones, different input patterns are extracted to make a map which can be fed to the matrix operation procedure. Experimental results show better performance than previous methods. The matrix operation method presented in this paper is new to the society of Reed Muller circuits synthesis and provides solid mathematical foundations.

• Communications for Statistical Applications and Methods
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• v.18 no.3
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• pp.377-389
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• 2011

A higher quality level is generally perceived by customers as improved performance by assigning a correspondingly higher satisfaction score. The third generation index $C_{pmk}$ is more powerful than two useful indices $C_p$ and $C_{pk}$ that have been widely used in six sigma industries to assess process performance. In actual manufacturing industries, process capability analysis often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Since these characteristics are related, it is a risky undertaking to represent the variation of even a univariate characteristic by a single index. Therefore, the desirability of using vector-valued process capability index(PCI) arises quite naturally. In this paper, we consider more powerful vector-valued process capability index $C_{pmk}$ = ($C_{pmkx}$, $C_{pmky}$)$^t$ that consider the univariate process capability index $C_{pmk}$. First, we examine the process capability index $C_{pmk}$ and plug-in estimator $\hat{C}_{pmk}$. In addition, we derive its asymptotic distribution and variance-covariance matrix $V_{pmk}$ for the vector valued process capability index $C_{pmk}$. Under the assumption of bivariate normal distribution, we study asymptotic confidence regions of our vector-valued process capability index $C_{pmk}$ = ($C_{pmkx}$, $C_{pmky}$)$^t$.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.3
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• pp.474-485
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• 2008

The purpose of this study is to examine the determinants and elements to enhance Korean international competitiveness, employing Porter's(1998) Diamond Model. Half of the 500 leading apparel exporters that were members of the Korea Apparel Industry Association in 2003 were selected as the target of this research. From May to June of 2003, survey questionnaires were sent to executives of these 250 companies in person or by telephone, e-mail, or fax. Seventy questionnaires were used for the final data anlysis. The items used were Reliability, Categorical Regression, and Frequency, using SPSS 11.5. The results were as follows: First, as a result of analyzing the influence of international competitiveness in Korean apparel industry, the firm's strategy, structure, and rivalry was the most influential factor. Others were related and supporting industries, government, chance, demand conditions, and factor conditions. Also, the elements that affect Korean international competitiveness were listed as the level of price competition in foreign markets, the level of labor cost, export marketing capacity, and exchange fluctuation. The most important element to improve the international competitiveness of the Korean apparel industry was a demand growth rate of the overseas markets(Demand Conditions), followed by the level of the labor costs(Factor Conditions), the capability of internationalization(Firm Strategy, Structure, and Rivalry), the change of currency(Chance), the quality and management of products(Demand Conditions), the capability of planning products(Firm Strategy, Structure, and Rivalry), free trade from 2005(Chance), and global sourcing strategy(Firm Strategy, Structure, and Rivalry). Korea's main rival country in apparel related and supporting industry factors is China. However, Korea has a higher level of technology development, quality, and price level than China.

• The Journal of Korean Academic Society of Nursing Education
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• v.28 no.4
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• pp.400-410
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• 2022

Purpose: This study aimed to understand the keywords and major topics of the educational goals and objectives of nursing educational institutions in South Korea. Methods: From May 10 to May 20, 2022, the educational goals and objectives of all 201 nursing educational institutions in South Korea were collected. Using the NetMiner program, degree and degree centrality, semantic structure, and topic modeling were analyzed. Results: The top keywords and semantic structures of educational goals included 'respect for human (life)-spirit-science-based on, global-competency-professional nurse-nursing personnel-training, professional-science-knowledge-skills, and patients-therapeutic care-relationship.' The educational goals' major topics were clients well-being based on science and respect for human life, a practicing nurse with capabilities and spirit, fostering a nursing personnel with creativity and professionalism, and training of global nurses. The top keywords and semantic structures of the educational objectives included 'holistic care-nursing-research-action-capability, critical thinking-health-problem solving-capability, and efficiency-communication-collaboration-capability.' The educational objectives' major topics were 'nursing professionalism, communication and problem-solving capability; a change of healthcare environments and a progress of nursing practices; fostering professional nurses with creativity and global capability; and clients' health and nursing practice.' Conclusion: Educational goals in nursing presented specific nursing values and concepts, such as respect for human life, therapeutic care relationships, and the promotion of well-being. Educational objectives in nursing presented the competencies of nurses as defined by the Korean Accreditation Board of Nursing Education (KABONE). Recently, the KABONE announced new program outcomes and competencies, which will require the revision of educational goals. To achieve those educational objectives, it is suggested that the expected level of competencies be clearly defined for nursing graduates.

• Korean Journal of Construction Engineering and Management
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• v.15 no.6
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• pp.3-15
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• 2014

Ever expanding overseas construction is one of the most important issues for Korean construction companies. Among these issues, strategies for overseas plant construction have widely been discussed, because the plant construction has features of low competitiveness and high ripple effects when compared with other construction sectors. In this sense, the purpose of this research is to evaluate the CM capability of Korean construction industry for overseas plant construction. Fourteen construction business functions and four techniques were defined first. Based on these functions and techniques, CM capability was quantified for As-Is (2013), To-Be (2018) and Gap analyses. Findings of this research reveal that 1) capability for construction is quite competent, 2) capabilities for planning, design management, contracting, and risk management are found to be relatively low, where higher value can be added. In addition, it is found that R&D needs to be extended to develop systemized management techniques. It is also required to secure specialists and original technologies at national industrial level.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.407-412
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• 2000

Response surface method is employed in optimizing the acoustic performance of automotive engine-cooling axial fans. The effects of modifications in blade geometry on noise reduction are investigated. Taking the far-field noise level as the objective, a quadratic response surface is constructed utilizing D-Optimality condition as the candidate-points selection criteria. It is shown that the quadratic model exhibits an excellent fitting capability resulting in the blade design with low far-field noise level.