• Journal of Communications and Networks
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• v.15 no.5
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• pp.486-495
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• 2013

In this article, we suggest a two-dimensional genetic algorithm (GA) method that applies a cognitive radio (CR) decision engine which determines the optimal transmission parameters for multicarrier communication systems. Because a CR is capable of sensing the previous environmental communication information, CR decision engine plays the role of optimizing the individual transmission parameters. In order to obtain the allowable transmission power of multicarrier based CR system demands interference analysis a priori, for the sake of efficient optimization, a two-dimensionalGA structure is proposed in this paper which enhances the computational complexity. Combined with the fitness objective evaluation standard, we focus on two multi-objective optimization methods: The conventional GA applied with the multi-objective fitness approach and the non-dominated sorting GA with Pareto-optimal sorting fronts. After comparing the convergence performance of these algorithms, the transmission power of each subcarrier is proposed as non-interference emission with its optimal values in multicarrier based CR system.

• Asia pacific journal of information systems
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• v.16 no.4
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• pp.27-47
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• 2006

Software companies try to upgrade the level of technology and quality of their products by adopting Software Process Improvement (SPI). First of all, the companies must understand affecting factors based on various environmental view points in order to acquire competitive advantage. In this study, a research model gets started on the basis of literature reviews, and identifies SPI factors that affect the maturity levels of organizations. Organizational members and assessment types are chosen as moderating factors. An empirical research has been made for analyzing the causal relationships among affecting factors and CMM levels. The results of this study will suggest several implications to decision makers who handle SPI issues.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.2
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• pp.1-9
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• 2012

Wireless sensor nodes are widely used for various applications such as environmental monitoring. In this paper, the RSSI and PER are measured for the indoor environment with the various interferences such as obstacles(concrete walls, steel doors) and the 2.4GHz wireless LAN interference. Also, the RSSI and PER are measured for the outdoor environments. From the measured values of the RSSI and PER, the guideline for the stable operation of the wireless sensor network is suggested.

• Asia pacific journal of information systems
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• v.12 no.4
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• pp.139-172
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• 2002

Comtemporary firms need capability of acquiring external knowledge and internalizing it to cope with environmental fluctuation. The paper analyzes the impact of absorptive capacity, an ability to recognize and utilize external knowledge, on knowledge acquisition of the firm, and examines the role of trust in the knowledge acquisition process. Data were collected from 84 domestic companies that had adopted ERP packages. The results indicate that prior experiences of knowledge acquisition, communication mechanism, and conflict resolution mechanism affect knowledge acquisition positively. Among those independent variables, communication mechanism and conflict resolution mechanism significantly and positively related with trust. Trust is, in turn, positively associated with knowledge acquisition. Meanwhile, previous knowledge base and prior relationship with the knowledge provider do not affect knowledge acquisition. Further, the results provide evidence that trust plays a mediating role between other absorptive capacity factors and knowledge acquisition.

• Asia pacific journal of information systems
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• v.11 no.3
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• pp.63-89
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• 2001

The purpose of this research is to develop strategic alternatives for the high-tech products development by comparatively studying characteristics of the industry and R&D structures in Korea and the US. Some of the environmental, strategic, organizational and project teams' characteristics are studied. Data were collected from Korea and US high-tech companies through interviews and questionnaires and event analysis method was used to analyze them. The findings are as follows: First, when the level of market concentration is high, cycle time tends to be longer. Therefore, if there are many competitors in the market, new products development should be swift due to competitive pressures. Second, the developmental strategy should be directed toward the existing customers to speed up new products development. That is, a defensive strategy would result in a shorter cycle time and response time compared to a strategy directed to a niche market. Third, when the level of formalization is high, cycle time tends to be shorter. This means that formal procedures for new products idea development or new products development policies shorten new products development time.

• Transactions of the Society of Information Storage Systems
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• v.6 no.1
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• pp.18-24
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• 2010

The performance of the speech recognition mainly depends on uncertain factors such as speaker's conditions and environmental effects. The present study deals with the speech recognition of a number of multi-syllable isolated Korean words using soft computing techniques such as back-propagation neural network, fuzzy inference system, and fuzzy neural network. Feature patterns for the speech recognition are analyzed with 12th order thirty frames that are normalized by the linear predictive coding and Cepstrums. Using four models of speech recognizer, actual experiments for both single-speakers and multiple-speakers are conducted. Through this study, the recognizers of combined fuzzy logic and back-propagation neural network and fuzzy neural network show the better performance in identifying the speech recognition.

• Management & Information Systems Review
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• v.5
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• pp.103-122
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• 2000

In recent years many companies have faced with significant environmental changes. To cope with these changes, companies have shown considerable interest and commitment to innovation, In their quest for superior performance, these companies have explored different types and sources of innovation. This study examines how competitive strategy influences companies' emphasis on different innovation types (product, administrative. and process) and sources (incubative, acquisitive and imitative). This study suggests that different strategies are associated with distinct patterns of innovation types and sources. Further, the fit between competitive strategies and innovation types and sources is associated with superior company performance. Based on this concept this study suggests several hypotheses. These hypotheses, if supported by empirical study, will be very useful to the company to improve financial performance.

• Asia pacific journal of information systems
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• v.13 no.3
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• pp.23-39
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• 2003

Recently, many organizations in various industries have introduced e-business for the purpose of adding value to their business. But, the e-business model has not existed before and so, it is difficult to analyze clear effectiveness. It frequently does not live up to an organization's expectations. It is due to an absence of environmental changes analysis in the new model, not by a new model itself. System Dynamics(SD) may provide effective results as a tool of analysis for the new model. This research shows the analysis of the effects of a simulated e channel model, which was expanded from existing channel modeling with actual data in basic materials industries. The results show average prices increasing by auction process on the e-market and an increase in sales. So, by increasing the speed of sale revolution stock expenses are reduced. Additionally, we applied a possible scenario to the developed simulation model and investigated strategic issues to draw desirable strategies with market changes.

• Asia pacific journal of information systems
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• v.13 no.3
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• pp.41-62
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• 2003

This study investigated the current status and characteristics of strategic alliances attempted by domestic internet businesses. Specifically, this study surveyed competitive environmental characteristics of partner companies involved, alliance period, types of partner companies, motives of alliances, types of alliances, success and failure factors and satisfaction toward the alliances. Major findings were: first, alliances between portal companies and content producers; portal companies and internet services; e-commercial sites and internet services were the most frequent partnerships engaged. Second, the most important motive for and type of the strategic alliance were: 'the commercialization and marketing of new product' and 'joint distribution and marketing agreement' respectively. Third, the most important factor for the successful alliance was 'a close examination of partners' core business value and competence'; and the factor most hindering the successful alliance was 'a discrepancy on capabilities of partners' core personnel. Finally types of internet business were significantly related to perceived satisfaction toward strategic alliance.

• Journal of the Ergonomics Society of Korea
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• v.28 no.1
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• pp.53-60
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• 2009

The present study was intended to suggest a process of physical user interface (PUI) design guideline development, which was validated with mobile phones. The process consisted of five stages including component and dimension analysis, function and environment analysis, evaluation criterion generation, literature review, and design guideline development. The process was applied to develop 19 mobile phone PUI design guidelines by identifying 28 components, 9 dimensions, 51 functions, 7 environmental conditions, and 15 criteria. The systematic approach of the process would be useful for manufacturers to develop design guidelines in an efficient manner.