فهرست مطالب

International Journal of Information Science and Management
Volume:2 Issue: 1, Jan-Jun 2004

  • تاریخ انتشار: 1382/05/11
  • تعداد عناوین: 7
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  • A. R. Zolghadr Asli, E. Goodarzi, M. Moosavinezhad Pages 3-12
    This paper presents a full duplex, real time implementation of ITU-T G.723.1 [7,8] speech coder using the TMS320C5402 DSP chip which is based on a 16 bit fixed-point architecture. An optimization method is proposed in order to reduce the total necessary cycle time consumed in real-time implementation. The Multi-Pulse Maximum Likelihood Quantization (MP-MLQ) excitation search block which is the most computation-intensive block in the coder is restructured to reduce the algorithmic redundancy. In addition, efficient filtering methods and memory management are used for further optimization. The bit-exact verification with the ITU test vectors and performance evaluation aspects are also discussed in this paper.
  • N. Faghih Pages 13-28
    This paper studies the sequential sampling scheme, as a solution to the problem of aliasing, where the sampling interval is restricted to a minimum allowable value DT. In the sequential sampling, the signal is sampled at intervals of DT, DT+Dt, DT+2Dt, DT+3Dt,. ..; where Dt < DT and may be selected as desirable. The sequential sampling is, however, analyzed and it is proven that, when the ratio DT/Dt is an integral number, the associated spectral estimates give a Nyquist frequency. This sampling scheme can, therefore, be employed to yield a required cut-off frequency. The autocorrelation function estimation from the sequentially sampled data is then considered and the approach to this is discussed. Simulation studies are also used for empirical investigations of the sequential sampling. Furthermore, since with this sampling scheme no estimates of the autocorrelation coefficients are available in the initial time interval from 0 to DT, the initial autocorrelation coefficients estimation method is applied to solve this problem. This, in addition, provides some empirical studies of the latter approach. Moreover, the application of the autocorrelation function extrapolation method is considered, as a means of minimizing the sampling time and costs. The contribution of the sequential sampling in obtaining a desired cut-off frequency, is also demonstrated by data simulation.
  • C. C. Jayasundara Pages 29-39
    The aim of this study is to discuss and critically review the Intelligent Agents (IA) and their recent developments. The report will particularly focus on the area of Intelligent Agents and information retrieval and how this technology is aiding users of databases. This report commences with a discussion of what Intelligent Agents are and it reviews the qualities they are generally expected to have and settles on the definition of an intelligent agent as a software entity. IA possess basic qualities such as autonomy, co-operation and learning. Then the report critiques the current state of IA technology by examining the technological, social, ethical and some of the legal issues. It further examines the implications of this technology for the reason that computer and information professionals have already recognised that there are a number of problems and issues surrounding the IA terminology and technology which must be resolved as soon as possible in order to acquire the utmost benefit from this technology. Although the Agents offer substantial advantage to users, the very nature of the IA paradigm leads to a number of ethical, social, technical and legal problems, common to all agent-based applications.
  • R. Ghasemiyeh, F. Li Pages 41-62
    Despite the fact that IT has become a fundamental variable for organizational design very few studies have been done to explore this vital issue in a systematic and convincing fashion. Indeed, the small amount of information and few theories available on organizational design in general and much less on the effects of IT on organization design is surprising. Most studies on the effects of IT on organizational design describe IT in general ways which have led to a non-generalizable and even contradictory result. The divergence in findings of previous research to some extent arises partly from lack of systematic approach to evaluate all the variables affecting organizational design. The current research attempts to address this problem by developing a contingency framework within which the impact of information technology (IT) on organizational design variables and simultaneously a number of the variables of interest and their relationship together are explored. To pursuit its objectives, in the first step, direct effects of IT on four organizational design variables (decision making, control, positions and formalisation) will be examined. Second, in addition to evaluating direct effects of IT, based on a conceptual theory in framework of FIT as gestalts approach, we also viewed this relationship from a contingency theory perspective at three levels organizational, individual and technological. In order to obtain rich data to explain the processes of change, while still being able to quantitatively measure and statistically analyze the impacts of advanced technologies on organizational design, a survey instrument will be utilized with target population of 400 Iranian manufacturing companies.
  • Gh. A. Montazer, A. Bahreininejad Pages 63-72
    The projection of Information and Communication Technology (ICT) has begun to have its impact in Iran. The benefits gained from ICT are widely accepted and the Iranian government is encouraging the country for adopting ICT practices. E-learning is an important branch of ICT which has attracted the attention of many people, especially those in educational and academic sectors. However, e-learning requires a great deal of vigilance compared with other ICT branches such as for example, e-business. This paper reviews the main prospects for e-learning and defines certain aspects for its implementation in Iran, offering some suggestions for the future.
  • S. Rezaei Sharifabadi Pages 73-80
    University libraries are shifting from custodial to an access role in a rapidly evolving networked society. Within the campus, it is the library which seeks open access to all types of information and encourages free intellectual inquiry. If the library is to make its claim as the "heart of the university" a reality, it is critical for librarians to obtain the needed skills in the provision and promotion of information services to meet the research, teaching and learning needs of the university. The paper will examine a number of ways in which the rapid growth of the Internet, as well as the emergence of new information technologies, impact the university library''s mission statement and goals. The paper concludes that the new environment requires a new technical set of competencies for librarians which were not previously required.
  • M. Bagheri Pages 81-94
    A glance at the growth and development of vocabulary control in Persian will make it clear that the process can be divided into three distinct stages: 1. Preparation of lists of Persian terms selected by documentation centers during the indexing process. 2. Translation into Persian of the thesauri available in English and French languages. 3. Compilation of thesauri in Persian based on warranted terms derived from the terminology found in Persian documents, indexed by various centers in Iran. Nowadays, at least eleven Persian Thesauri are available with Iranian documentation centers, while others are in the making.