• Journal of Power Electronics
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• v.15 no.2
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• pp.530-543
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• 2015

Air-cooling method is adopted on the basis of the requirements for the thermal stability and convenient field use of an electrical source transmitter. The power losses of the transmitter are determined after calculating the losses of the alternating current (AC)-direct current (DC) power supply, the constant-current circuit, and the output circuit. According to the analysis of the characteristics of a heat sink with striped fins and a fan, the engineering calculation expression of the Nusselt number and the design process for air-cooled dissipation are proposed. Experimental results verify that the error between calculated and measured values of the transmitter losses is 12.2%, which meets the error design requirements of less than 25%. Steady-state average temperature rise of the heat sink of the AC-DC power supply is $22^{\circ}C$, which meets the design requirements of a temperature rise between $20^{\circ}C$ and $40^{\circ}C$. The transmitter has favorable thermal stability with 40 kW output power.

• Journal of Korean Institute of Industrial Engineers
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• v.43 no.2
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• pp.127-134
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• 2017

For product or process design and development, it is common to optimize multiple responses (characteristics) based on experimental data. To determine optimal conditions, we need to design the experiment, estimate a proper model for each response, and optimize the multiple responses simultaneously. There are several techniques and many research results on optimizing multiple responses simultaneously, when the experimental data are available. However, the experimental design issue for optimizing multiple responses has not been discussed yet. This paper proposes some idea on how to plan screening design when requirements for multiple performance characteristics are to be met in developing new products. A screening design procedure is developed for securing the requirements of multiple responses. Initial design factors are classified into three categories; specific, non-conflicting common, and conflicting common. After screening experiments, follow-up design region search method is suggested with respect to the most unsatisfied or important response, or overall desirability. A case study on a synthesis of melamine formaldehyde resin is presented to illustrate the procedure and to show the validity of the approach.

• Design Convergence Study
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• v.18 no.3
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• pp.1-14
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• 2019

General finger splint manufactured and sold domestically could have been of great help to patients with disabilities due to damage to the body's. However, it reminded the wearer of his disability that he wanted to hide. This has had a negative effect on the psychological side of self-absorption and depression. If this avoids or rejects wearing, the role of ancillary rehabilitation is lost. This does not meet the user's requirements. Thus, in this study, 3D printing was used to better reflect user requirements. Next, the study examined existing prior studies to identify the characteristics and criteria of each study. It also examined medical finger aids that were being sold in the auxiliary device market. The assessment criteria were derived by compiling and interpreting user surveys of each finger splint device. Based on the evaluation criteria derived, the design guidelines for finger splint were presented using FDM-style 3D printers. Finally, we proposed a finger splint design according to the proposed design guideline.

• Knowledge Management Research
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• v.14 no.1
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• pp.121-132
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• 2013

In education, innovative ways of teaching and learning are always under development and keep being proposed with advanced concepts since the ancient times. Student-centered learning, problem-based learning and cooperative learning have been three major trends under development in secondary education research and practice more than a decade or so. Combined with advanced information and communication technologies, these trends will greatly transform the way we teach and learn in classroom environment and may change the classroom environment itself, into a more interactive and self-centered coaching type environment. In this study, a smart environment that utilizes advanced information technology devices and network is conceptualized, accommodating requirements contained and proposed in the recent trendy pedagogies. Pedagogical cases discussed in these trends are analyzed in detail, producing requirements for such a learning and coaching environment. These requirements are modeled using unified modeling language, leading to a proposal of a basic architecture for an information system supporting this environment.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.16 no.4
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• pp.41-48
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• 2008

Functional analysis of air transport mission is conducted to establish the performance requirements of the commercial transport designs. The analysis process begins by making a top-down analysis to the aircraft system level mission functions. Correctly interpreting the top-level performance requirements is the first step in designing and building an aircraft system. Each function and sub-function is allocated and examined to the aircraft level and flight operations phase to optimize the system performance and design requirements, such that these lower-level requirements can be traced back to the top-level requirements they are designed to fulfill. Special attention is given to making sure all interfaces, both internal and external, are addressed. The results are also in good resources of functional hazard assessment involved in certification processes.

• Journal of Information Technology Application
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• v.3 no.1
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• pp.91-108
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• 2001

Participatory Design (PD) community recognized that identification of use case scenarios describing possible uses of the future system is beneficial for users to identify their system requirements. However, brainstorming is a typical methodology for users to create use case scenarios during PD session, which heavily depend on the people skill and experiences of the analysts. The objective of this study is to develop a theoretical framework for automatic generation of requirement scenarios. Automatically generated scenarios serves as a menu of the possible user requirements from which user group can start to generate ideas about their requirements. The convergent approach taken here is novel in that the generated scenarios describe system requirements as well as the business process requirements in which the system operates. A context-sensitive grammar is used to generate the context relevant requirement scenarios.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1821-1828
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• 2010

In this study we suggest a method of optimization of verification hierarchy structure and system requirements management by using a verification matrix with traceability consideration. Verification items were gathered in the process of CDR(Critical Design Review), and analyzed with respect to requirements traceability structure. Missed or overlapped items were adjusted, and cross-correlated items between sub-systems were clustered and rearranged in order to structurize verification requrements (VRs). Those VRs are to be used as a guideline for the test and evaluation planning, development of test items and procedure, and system requirements management throughout the system integration stages.

• Journal of Platform Technology
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• v.11 no.5
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• pp.3-15
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• 2023

Requirements traceability link information is the basis for determining whether requirement change requested throughout the software development life cycle should be reflected in the system. Setting up complete requirements traceability links requires considerable effort. However, the commensurate benefits can be obtained in later development or further maintenance phases. For this reason, setting up and managing requirements traceability links in the software development phase are tasks that cause considerable resistance to developers. This study proposes a method for generating requirement traceability links in business applications. The key feature of the proposed method is that the traceability link from the requirements element, which is the basis of the corresponding element to the analysis element, is automatically established at the same time the elements of the analysis model are identified. This can be a way to reduce developer effort while increasing the efficiency of the traceability model. A case study on a Course Registration System demonstrates the feasibility of applying the proposed requirements traceability management method to actual software development.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.79-87
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• 2021

This study suggests a design process for vibrotactile interface that can apply haptic perception factors reflecting human tactile mechanisms. This process consists of 4 stages: the haptic sense requirement analysis stage, the haptic element analysis stage, the haptic perception factor analysis stage, the haptic requirement detailed design, and the prototype implementation stage. The advantage of this design process is that unnecessary tasks can be excluded in deriving and implementing user requirements, by applying haptic perception factor analysis, and the biggest feature is that research results on ergonomic mechanisms can be reflected in the haptic design, completes prototype development simultaneously while determining the haptic requirements statement by performing user evaluation, usability testing, and haptic feature optimization tasks simultaneously. This design process includes all stages from user requirements to haptic function detailed design and prototype implementation, so it is expected that general developers who lack expertise in haptic will also be able to design user-centered designs, enabling design and implementation of haptic functions at a certain level.

• Steel and Composite Structures
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• v.3 no.6
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• pp.451-474
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• 2003

Details are given of a cold-formed steel portal framing system that uses simple bolted moment-connections for both the eaves and apex joints. However, such joints function as semi-rigid and, as a result, the design of the proposed system will be dominated by serviceability requirements. While serviceability is a mandatory design requirement, actual deflection limits for portal frames are not prescribed in many of the national standards. In this paper, a review of the design constraints that have an effect on deflection limits is discussed, and rational values appropriate for use with cold-formed steel portal frames are recommended. Adopting these deflection limits, it is shown through a design example how a cold-formed steel portal frame having semi-rigid eaves and apex joints can be a feasible alternative to rigid-jointed frames in appropriate circumstances.