• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.9
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• pp.37-44
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• 2002

This paper proposes efficient digital hardware design method by using fixed weight of pre-trained neural network. For this, arithmetic operations of PEs(Processing Elements) are represented with matrix-vector multiplication. The relationship of fixed weight and input data present bit-level array structure architecture which is consisted operation node. To minimize the operation node, this paper proposes node elimination method and setting common node depend on bit pattern of weight. The result of FPGA simulation shows the efficiency on hardware cost and operation speed with full precision. And proposed design method makes possibility that many PEs are implemented to on-chip.

• Journal of IKEEE
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• v.16 no.2
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• pp.145-152
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• 2012

This paper is the Software Hazard Analysis (SWHA) which will study the managerial process and the technical methode and techniques inherent in the performance of software safety task within the Military Aircraft System Safety program. This SWHA identifies potential hazardous effects on the software intensive systems and provides a comprehensive and qualitative assessment of the software safety. The purpose of this paper is to identify safety critical functions of software in Military A/C. The identified software hazards associated with the design or function will be evaluated for risks and operational constraint to further improve the software design requirement, analysis and testing efforts for safety critical software. This common SWHA, the first time analysis in KOREA, was review all avionics OFP(Operational Flight Program), and focus only on software segments which are safety critical. This paper provides a important understanding between the customer and developer as to how the software safety for the Military A/C will be accomplished. It will also provide the current best solution which may as one consider the necessary step in establishing a credible and cost-effective software safety program.

• Corrosion Science and Technology
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• v.16 no.2
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• pp.76-84
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• 2017

In the construction of subsea oil and gas developments, it is increasingly common that subsea oil and gas equipment will be installed in subsea well before final hookup and production. Installation of wellheads, subsea hardware, pipelines, and surface facilities (platforms, FPSO, FLNG, connected terminals, or gas plants) are increasingly driven by independent cost and vessel availability schedules; this gives rise to requirements that the subsea facilities must be stored in the seabed for a specific time. In addition, schedule delays, particularly in the installation or startup of the connected platform, FPSO, FLNG, or onshore plant may cause unexpected extensions of the intended storage period. Currently, there are two methods commonly used for storage subsea facilities in the seabed: dry parking and wet parking. Each method has its own risks, challenges, and implications for the facility life and its integrity. The corrosion management and preservation method selection is a crucial factor to be considered in choosing the appropriate storage method and achieving a successful seabed storage. An overview of those factors is presented, along with a discussion on the internal corrosion threats and assessments.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.1
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• pp.102-108
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• 2000

The comparative evaluation/analysis of the initiation technologies currently being used, and the advanced initiation technologies currently being developed lot the aerospace and defense applications was performed. The evaluation criteria used were the compliance, performance, reliability, safety, and cost. The results clearly indicate that there is no one single initiation technology that will satisfy entire spectrum of initiation system requirements. Each initiation system architecture would require different initiation technologies that will satisfy the overall system performance requirements. However, laser initiation, particularly, the laser diode initiation has been getting more attention in recent years. The laser diode initiation, for most part, eliminates EMI and ESD concerns. In addition, laser diode initiation system can also be designed into relatively small packages, are optically connected systems by very light weight cables, are relatively easily designed to meet variety of initiation system requirements. Due to the these compelling factors, laser diode initiation has potential of becoming common initiation systems for many different aerospace and defense application.

• Structural Engineering and Mechanics
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• v.55 no.5
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• pp.965-977
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• 2015

Determination of dynamic parameters of a structure such as predominant frequency and damping ratio is one of the most important subjects in dynamics of structures. Different methods are used to determine predominant frequency. These methods are different in the cost, implement accessibility, accuracy, speed, applicability in different conditions, simplicity of calculations and required data accessibility. Calculation of damping ratio by using common experimental procedures is very difficult and costly, then it is assumed as a constant value in most calculations. Microtremor measurements and using spectral ratio method to determine the predominant frequency and damping ratio of structure is of interest in recent years. In this paper, as a case study, the effects of retrofitting on structural dynamic parameters of two four-story buildings by using microtremor measurements and also finite element analysis, is investigated. The results of this study show that microtremor measurements can be utilized to assess the improvement of dynamic behavior of the retrofitted structure and the effectiveness of the method of retrofitting.

• Membrane and Water Treatment
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• v.6 no.1
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• pp.53-75
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• 2015

This paper provides an overview of the role of membranes in bioelectrochemical systems (BESs). Bioelectrochemical systems harvest clean energy from waste organic sources by employing indigenous exoelectrogenic bacteria. This energy is extracted in the form of bioelectricity or valuable biofuels such as ethanol, methane, hydrogen, and hydrogen peroxide. Various types of membranes were applied in these systems, the most common membrane being the cation exchange membrane. In this paper, we discuss three major bioelectrochemical technology research areas namely microbial fuel cells (MFCs), microbial electrolysis cells (MECs) and microbial desalination cells (MDCs). The operation principles of these BESs, role of membranes in these systems and various factors that affect their performance and economics are discussed in detail. Among the three technologies, the MFCs may be functional with or without membranes as separators while the MECs and MDCs require membrane separators. The preliminary economic analysis shows that the capital and operational costs for BESs will significantly decrease in the future due mainly to differences in membrane costs. Currently, MECs appear to be cost-competitive and energy-yielding technology followed by MFCs. Future research endeavors should focus on maximizing the process benefits while simultaneously minimizing the membrane costs related to fouling, maintenance and replacement.

• Journal of the Semiconductor & Display Technology
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• v.7 no.2
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• pp.23-27
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• 2008

Recently, regulation for THD (Total Harmonic Distortion) such as IEC 61000-3-2, IEEE 519 is being reinforced about a product which directly connects to AC line in order to prevent distortion of common power source in electronic equipment and electrical machinery. In order to satisfy these regulations, conventional circuits were used two-stage structure attached power factor correction circuit at ahead of converter but this method complicate the circuit and then a number of element increases thereupon the cost of production rises. in this paper, we propose a high efficiency single-stage 300W PFC fly-back converter that improved power factor and efficiency than conventional two-stage power module.

• Perspectives in Nursing Science
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• v.8 no.2
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• pp.148-155
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• 2011

Purpose: The aims of this study were to (1) summarize the HF self-management interventions and (2) identify gaps and priorities for further investigation. Methods: A computer search of the literature over the past decade yielded 9 HF self-management studies. Six studies used non-experimental design; only 3 (33%) studies used quasi-experimental design which were included in this review. Results: The three pivotal HF self-management interventions studies were important because they highlight the positive effects of self-management compliance and other quality of life outcomes as well as discussing various issues. The informational booklet and telephone follow-up were the most common modalities in these interventions. The periodic telephone counseling offered in 2 studies effectively facilitated patient self-management compliance. There were some methodological flaws such as small sample sizes (range 8~21 in each group) and lack of experimental designs, long-term follow-up, and random group assignment. Additionally, the use of valid, reliable outcome measures is necessary to compare the effects of the interventions worldwide. Conclusion: More clinical evidence on HF self-management is needed using a larger sample size and the efficacy needs to be tested for various outcomes, including morbidity, mortality, and health care cost.

• Journal of Families and Better Life
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• v.21 no.4
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• pp.41-53
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• 2003

The purpose of this study is to understand and verify the incentives as an important market environment and to help consumers use them effectively, and consequently to improve the consumer welfare. This study examined the representative incentive, the sales promotions which can effect on the consumer decision making process and current issues of them. For the purpose, a coffee specialty store was hypothesized and the subjects were 20∼30 years old, since the sales promotions can be more effective toward the younger consumers making their decisions low-involvement goods and services. The conclusions can be summarized as follows; Consumers understand the advantages and disadvantages of sales promotion very well, and use them rationally and usefully to maximize their satisfaction. the sales promotions act as incentives in the all steps of decision making processes. Generally, consumers prefer to get things at a good price, so in this survey, the discount coupons and the point accumulative membership had more effect than others. Consumers pointed out controversial issues of the sales promotions as follows: the sales promotions could bring about cost rising and unnecessary and/or impulse buying, and stir up speculative motivation. These are common serious problems in the sales promotions. The sales promotions are very useful tools in promoting sales but not fundamental in the long run. Marketers and manufacturers should keep it in mind that the best way to satisfy the consumers is to keep all things in good quality and moderate price.

• Journal of Construction Engineering and Project Management
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• v.4 no.4
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• pp.41-46
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• 2014

Indian Construction industry is large, volatile, and requires tremendous capital outlays. Typically, the work offers low rates of return in relation to the amount of risk involved. A unique element of risk in the industry is the manner in which disputes and claims are woven through the fibre of the construction process. Delay is generally acknowledged as the most common, costly, complex and risky problem encountered in construction projects. Because of the overriding importance of time for both the Owner and the Contractor, it is the source of frequent disputes and claims leading to lawsuits. The growing rate of delays is adversely affecting the timely delivery of construction projects. Presently construction industries are facing a lot of problems, considering that a paper assess construction stakeholder's perception to the causes of delays and its effects on project delivery. And also one case study is considered in this paper to elicit responses from construction stakeholders. The primary aim of this paper is to identify the perceptions of the different parties regarding causes of delays, the allocation of responsibilities and the types of delays, and method of minimizing the construction delays.