• Journal of the Korea Computer Industry Society
• /
• v.4 no.4
• /
• pp.517-522
• /
• 2003

As the Software development condition is changed into enlargement and complex, requirements generated in each step of Software development life cycle has important effects on the technique and management area. In this thesis, We propose so engineering approach for effective and systematic process and activities including Requirements acquisition and management based on activities proposed with Requirements Engineering and CMM that my special emphasis is putted on Software qualify improvement through the reduction of software development cost and danger.

• Journal of Positioning, Navigation, and Timing
• /
• v.8 no.4
• /
• pp.215-223
• /
• 2019

This paper analyzes navigation performances of the Korean Positioning System (KPS) constellation with respect to the orbit parameters which fulfills the specification requirements. Specifically, the satellite configuration and navigation requirements of KPS are explained, and the daily mean horizontal dilution of precision (HDOP) and satellite visibility on KPS coverage are analyzed to confirm the adequate orbit parameters. However, due to orbital slot saturation, geostationary-orbit (GEO) satellites may not be allocated in the original orbit as specified in the KPS requirements. Therefore, in a spanned window of 4 degrees from the reference longitude the navigation performance of each GEO satellite orbit is investigated.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.22-25
• /
• 2007

Industry faces a considerable challenge to meet the high demand for reduced impacts and improved environmental performance. With this current stream, railway industry launched a systematic scheme for environmental friendly EMU and its system. An assessment tool which evaluate the environmental impacts of the product through its entire life cycle has been developed. The next step to environmentally sound and sustainable product design, shortly ECODESIGN has come to be essential and necessary as well. Ecodesign requires to identify possible stakeholder requirements first. The paper illustrates way how to define stakeholder requirements in terms of environment and shows approach linking stakeholder requirements to environmental parameters.

• Asian Journal of Business Environment
• /
• v.5 no.3
• /
• pp.17-21
• /
• 2015

Purpose - This paper compares current requirements for depreciation accounting from the Financial Accounting Standards Board in America for equity securities and all debt securities with determinable fair value, and disclosure requirements related to the fair value of securities below registered cost with the requirements of the international Financial Reporting Standards Board and accounting standards committee. Research design, data, and methodology - Mini-review statements are examined relating to depreciation of investments in America and the Financial Accounting Standards depreciation of investments in Iran that meet the requirements of international reporting standards and the Iranian Accounting Standards Committee. Results - Accounting rules for depreciation of investments in securities requires a good deal of judgment. In particular, devaluation decisions during the recession and market crisis were controversial, although even with no clear guidelines on devaluation, sometimes such decisions were simple. Conclusions -Companies can choose from formal policies applied uniformly and documentations of interest to provide a summary of the principles and conclusions obtained through disclosure, enabling market participants to assess the entity's conclusions reasonably, thereby easing investor and market worries.

• Journal of Aerospace System Engineering
• /
• v.3 no.3
• /
• pp.39-44
• /
• 2009

Humans rely on the availability of a supply of gaseous oxygen for survival. If the minimal requirements for oxygen are not met, both mental and physical abilities and performance are degraded rapidly. So oxygen systems are required for the aircraft operating at high altitude to prevent physical and psychological problems, or loss of consciousness in an aircraft pilot, flight crew, or passengers. If oxygen system and equipments are to be included in the type design of an airplane, applicant should consider applicable airworthiness requirements and operating rules. In this paper we analyze the various oxygen system requirements for the type of aircraft, oxygen system, and operating conditions.

• Nuclear Engineering and Technology
• /
• v.46 no.1
• /
• pp.47-54
• /
• 2014

The protection of nuclear safety software is essential in that a failure can result in significant economic loss and physical damage to the public. However, software security has often been ignored in nuclear safety software development. To enforce security considerations, nuclear regulator commission recently issued and revised the security regulations for nuclear computer-based systems. It is a great challenge for nuclear developers to comply with the security requirements. However, there is still no clear software development process regarding security activities. This paper proposes an integrated development process suitable for the secure development requirements and system security requirements described by various regulatory bodies. It provides a three-stage framework with eight security activities as the software development process. Detailed descriptions are useful for software developers and licensees to understand the regulatory requirements and to establish a detailed activity plan for software design and engineering.

• Nuclear Engineering and Technology
• /
• v.51 no.2
• /
• pp.463-478
• /
• 2019

The most important non-functional requirements for dependability of any Embedded Real-Time Safety Systems are safety, availability and reliability requirements. System architecture plays the primary role in achieving these requirements. Compliance with these non-functional requirements should be ensured early in the development cycle with appropriate considerations during architectural design. In this paper, we present an application of system architecture modeling for quantitative assessment of system dependability. We use probabilistic model checker (PRISM), for dependability analysis of the DTMC model derived from system architecture model. In general, the model checking techniques do not scale well for analyzing large systems, because of prohibitively large state space. It limits the use of model checking techniques in analyzing the systems of practical interest. We propose abstraction based compositional analysis methodology to circumvent this limitation. The effectiveness of the proposed methodology has been demonstrated using the case study involving the dependability analysis of safety system of a large Pressurized Water Reactor (PWR).

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.4
• /
• pp.382-391
• /
• 2016

For safety-critical systems including railways, there has been a growing need for effective and systematic safety management processes. The outcomes of efforts in this area are international safety standards, such as IEC 61508, 62278, and ISO 26262. One of the principal activities in the safety process is hazard analysis. For this reason, considerable efforts have been directed toward methods of hazard analysis. On the other hand, the hazard analysis methods reported thus far appear to be unclear in terms of their relationship with the system design process. In addition, in some cases, the methods appear to rely heavily on information regarding the hardware and software components, the number of which is increasing. These aspects can become troublesome when design changes are necessary. To improve the situation, in this paper, hazard analysis was carried out using the result of functional analysis early in the concept development stage for a safety-critical system design. Because hazard analysis is carried out at the system level and the result is then used to develop the safety requirements, improvements can be expected in terms of the development time and cost when design changes are required due to changes in the requirements. As a case study, the generation of safety requirements for the development of light rail transit stations is presented.

• Journal of Engineering Education Research
• /
• v.22 no.2
• /
• pp.16-27
• /
• 2019

In order to note some points necessary for developing the cornerstone design course concentrating on conceptual design through that students acknowledge that engineering design is not to make things but to produce knowledge not only meet requirements of clients, users, and stake holders but also to solve problems, this paper describes the contents for the course that covers conceptual design as well as embodiment design, explains some ways and tools both for guiding students and for asking for study of lecture materials, and discuss things to be considered when faculty designs the course.

• Steel and Composite Structures
• /
• v.8 no.1
• /
• pp.53-83
• /
• 2008

A rational and efficient seismic design methodology for irregular space steel frames using advanced methods of analysis in the framework of Eurocodes 8 and 3 is presented. This design methodology employs an advanced static or dynamic finite element method of analysis that takes into account geometrical and material non-linearities and member and frame imperfections. The inelastic static analysis (pushover) is employed with multimodal load along the height of the building combining the first few modes. The inelastic dynamic method in the time domain is employed with accelerograms taken from real earthquakes scaled so as to be compatible with the elastic design spectrum of Eurocode 8. The design procedure starts with assumed member sections, continues with the checking of the damage and ultimate limit states requirements, the serviceability requirements and ends with the adjustment of member sizes. Thus it can sufficiently capture the limit states of displacements, rotations, strength, stability and damage of the structure and its individual members so that separate member capacity checks through the interaction equations of Eurocode 3 or the usage of the conservative and crude q-factor suggested in Eurocode 8 are not required. Two numerical examples dealing with the seismic design of irregular space steel moment resisting frames are presented to illustrate the proposed method and demonstrate its advantages. The first considers a seven storey geometrically regular frame with in-plan eccentricities, while the second a six storey frame with a setback.