Showing papers by "City University of Hong Kong published in 2001"

On the mathematical foundations of learning

Abstract: (1) A main theme of this report is the relationship of approximation to learning and the primary role of sampling (inductive inference). We try to emphasize relations of the theory of learning to the mainstream of mathematics. In particular, there are large roles for probability theory, for algorithms such as least squares, and for tools and ideas from linear algebra and linear analysis. An advantage of doing this is that communication is facilitated and the power of core mathematics is more easily brought to bear. We illustrate what we mean by learning theory by giving some instances. (a) The understanding of language acquisition by children or the emergence of languages in early human cultures. (b) In Manufacturing Engineering, the design of a new wave of machines is anticipated which uses sensors to sample properties of objects before, during, and after treatment. The information gathered from these samples is to be analyzed by the machine to decide how to better deal with new input objects (see [43]). (c) Pattern recognition of objects ranging from handwritten letters of the alphabet to pictures of animals, to the human voice. Understanding the laws of learning plays a large role in disciplines such as (Cognitive) Psychology, Animal Behavior, Economic Decision Making, all branches of Engineering, Computer Science, and especially the study of human thought processes (how the brain works). Mathematics has already played a big role towards the goal of giving a universal foundation of studies in these disciplines. We mention as examples the theory of Neural Networks going back to McCulloch and Pitts [25] and Minsky and Papert [27], the PAC learning of Valiant [40], Statistical Learning Theory as developed by Vapnik [42], and the use of reproducing kernels as in [17] among many other mathematical developments. We are heavily indebted to these developments. Recent discussions with a number of mathematicians have also been helpful. In

Product Innovation Strategy and the Performance of New Technology Ventures in China

Abstract: Investigating the effect of product innovation strategy on the performance of new technology ventures in China, we found the innovation-performance link was contingent on both environmental factors, including environmental turbulence and institutional support, and the relationship-based strategies of the ventures, such as strategic alliances for product development and political networking. Our results suggest the need for simultaneous consideration of environment- and relationship-based strategy factors as moderators in the discourse on product innovation strategy among new technology ventures.

An Empirical Investigation of the Effect of Market Orientation and Entrepreneurship Orientation Alignment on Product Innovation

Abstract: This article develops a concept of an alignment between market and entrepreneurship orientations and reports the results of a study designed to investigate its effect on a firm's product innovation. A sample of 181 firms was classified into four categories labeled as market/entrepreneurship orientation (ME), entrepreneurship orientation (EO), market-oriented (MO), and conservative (CO) firms. One-way ANOVA and planned contrast tests (PCT) were used to identify whether or not specific product innovation decisions, activities, and performance vary across the groups. The results indicate that these groups of firms significantly differ with respect to both subjective and objective measures of new product performance, and with product innovation strategies and activities pertaining to timing of market entry, product quality, marketing synergy, proficiency of market launch, and management support for innovation. Further, the findings suggest that these groups of firms are not significantly different with respect to perceived environmental hostility and intensity of market competition. This finding suggests that the groups of firms are robust across environments and that the findings presented in this study are not an artifact of environmental variation. Managerial and research implications of the results are discussed.

Robust fuzzy control of nonlinear systems with parametric uncertainties

Abstract: Addresses the robust fuzzy control problem for nonlinear systems in the presence of parametric uncertainties. The Takagi-Sugeno (T-S) fuzzy model is adopted for fuzzy modeling of the nonlinear system. Two cases of the T-S fuzzy system with parametric uncertainties, both continuous-time and discrete-time cases are considered. In both continuous-time and discrete-time cases, sufficient conditions are derived for robust stabilization in the sense of Lyapunov asymptotic stability, for the T-S fuzzy system with parametric uncertainties. The sufficient conditions are formulated in the format of linear matrix inequalities. The T-S fuzzy model of the chaotic Lorenz system, which has complex nonlinearity, is developed as a test bed. The effectiveness of the proposed controller design methodology is finally demonstrated through numerical simulations on the chaotic Lorenz system.

Intelligent Predictive Decision Support System for Condition-Based Maintenance

Abstract: The high costs in maintaining today’s complex and sophisticated equipment make it necessary to enhance modern maintenance management systems. Conventional condition-based maintenance (CBM) reduces the uncertainty of maintenance according to the needs indicated by the equipment condition. The intelligent predictive decision support system (IPDSS) for condition-based maintenance (CBM) supplements the conventional CBM approach by adding the capability of intelligent condition-based fault diagnosis and the power of predicting the trend of equipment deterioration. An IPDSS model, based on the recurrent neural network (RNN) approach, was developed and tested and run for the critical equipment of a power plant. The results showed that the IPDSS model provided reliable fault diagnosis and strong predictive power for the trend of equipment deterioration. These valuable results could be used as input to an integrated maintenance management system to pre-plan and pre-schedule maintenance work, to reduce inventory costs for spare parts, to cut down unplanned forced outage and to minimise the risk of catastrophic failure.

An optimal fuzzy PID controller

Abstract: This paper introduces an optimal fuzzy proportional-integral-derivative (PID) controller. The fuzzy PID controller is a discrete-time version of the conventional PID controller, which preserves the same linear structure of the proportional, integral, and derivative parts but has constant coefficient yet self-tuned control gains. Fuzzy logic is employed only for the design; the resulting controller does not need to execute any fuzzy rule base, and is actually a conventional PID controller with analytical formulae. The main improvement is in endowing the classical controller with a certain adaptive control capability. The constant PID control gains are optimized by using the multiobjective genetic algorithm (MOGA), thereby yielding an optimal fuzzy PID controller. Computer simulations are shown to demonstrate its improvement over the fuzzy PID controller without MOGA optimization.

Second language listening : theory and practice

Abstract: This book combines up-to-date listening theory with case studies of actual pedagogical practice. The paperback edition combines up-to-date listening theory with case studies of actual pedagogical practice. As an essential part of communicative competence, listening is a skill, which deserves equal treatment with the other basic skills of speaking, reading, and writing. The authors describe current models of listening theory and exemplify each with a textbook task. They address the role of technology in teaching listening, questioning techniques, and testing. This text is designed for use with both pre-service and in-service teachers who are involved in the teaching of listening or the design of pedagogic materials for listening.

Wavelet Analysis and Envelope Detection For Rolling Element Bearing Fault Diagnosis—Their Effectiveness and Flexibilities

Abstract: The components which often fail in a rolling element bearing are the outer-race, the inner-race, the rollers, and the cage. Such failures generate a series of impact vibrations in short time intervals, which occur at Bearing Characteristic Frequencies (BCF). Since BCF contain very little energy, and are usually overwhelmed by noise and higher levels of macro-structural vibrations, they are difficult to find in their frequency spectra when using the common technique of Fast Fourier Transforms (FFT). Therefore, Envelope Detection (ED) is always used with FFT to identify faults occurring at the BCF. However, the computation of ED is complicated, and requires expensive equipment and experienced operators to process. This, coupled with the incapacity of FFT to detect nonstationary signals, makes wavelet analysis a popular alternative for machine fault diagnosis. Wavelet analysis provides multi-resolution in time-frequency distribution for easier detection of abnormal vibration signals. From the results of extensive experiments performed in a series of motor-pump driven systems, the methods of wavelet analysis and FFT with ED are proven to be efficient in detecting some types of bearing faults. Since wavelet analysis can detect both periodic and nonperiodic signals, it allows the machine operator to more easily detect the remaining types of bearing faults which are impossible by the method of FFT with ED. Hence, wavelet analysis is a better fault diagnostic tool for the practice in maintenance.

Relationships between tissue concentrations of polycyclic aromatic hydrocarbons and antioxidative responses of marine mussels, Perna viridis

Abstract: Local mussels, Perna viridis, were transplanted from a relatively clean site to various polluted sites in Hong Kong. After a 30-day field exposure, different antioxidant parameters including glutathione S transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), NADPH DT-diaphorase (DT-d), glutathione (GSH) and lipid peroxidation were quantified, and tissue concentrations of benzo[a]pyrene (B[a]P) as well as a total of five polycyclic aromatic hydrocarbons (PAHs) with potential carcinogenicity were determined for individual mussels. Results indicated that: (1) tissue concentrations of B[a]P and total PAHs from the same site were highly variable; (2) gill SOD, DT-d and lipid peroxidation showed no response to tissue pollutants: (3) the majority of the antioxidant parameters were induced by increasing tissue pollutant concentrations; and (4) amongst the various parameters, oxyradical scavenger GSH [ best correlated with tissue concentrations of pollutants.

Critical success factors revisited: success and failure cases of information systems for senior executives

Abstract: The literature suggests the existence of critical success factors (CSFs) for the development of information systems that support senior executives. Our study of six organizations gives evidence for this notion of CSFs. The study further shows an interesting pattern, namely that companies either “get it right”, and essentially succeed on all CSFs, or “get it completely wrong”, that is, fall short on each of the CSFs. Among the six cases for which data were collected through in-depth interviews with company executives, three organizations seemed to manage all the CSFs properly, while two others managed all CSFs poorly. Only one organization showed a mixed scorecard, managing some factors well and some not so well. At the completion of the study, this organization could neither be judged as a success, nor as a failure. This dichotomy between success and failure cases suggests the existence of an even smaller set of “meta-success” factors. Based on our findings, we speculate that these “meta-success” factors are “championship”, “availability of resources”, and “link to organization objectives”.

Minimal Structures: From Jazz Improvisation to Product Innovation:

Abstract: This paper demonstrates how the art form jazz improvisation can be applied to organizational innovative activities, focusing specifically on product innovation. In the past, the literature on product innovation focused on well-planned approaches which followed a clearly-understood structure based on a rational-functionalist paradigm. However, it is becoming increasingly evident that this model is inappropriate in today's highly competitive business environment. A balance between structure and flexibility seems to be an appropriate way to manage the contradicting demands of control and creativity faced by organizations in highly competitive environments. Jazz improvisation provides this synthesis through the concept of `minimal structures'. We characterize the minimal structures that allow jazz improvisers to merge composition and performance, and then proceed to apply this approach to new product development.

Research Perspectives on English for Academic Purposes

Abstract: Preface Introduction to Part I 1. Issues in EAP: A preliminary perspective John Flowerdew and Matthew Peacock 2. Language use, language planning and EAP Chris Kennedy 3. EAP-related linguistic research: An Intellectual History John M. Swales 4. Linguistic research and EAP pedagogy Brian Paltridge 5. International scientific English: The language of research scientists around the World Alistair Wood 6. Discipline specificity and EAP Caroline Clapham 7. World Englishes: issues in and from academic writing assessment Liz Hamp-Lyons and Bonnie Wenxia Zhang 8. Addressing issues of power and difference in ESL academic writing Suresh Canagarajah 9. I'll go with the group": Rethinking 'Discourse community' In EAP Sue Starfield 10. EAP Assessment: issues, models, and outcomes Geoff Brindley and Steven Ross Introduction to Part II 11. The EAP curriculum: issues, methods, and challenges John Flowerdew and Matthew Peacock 12. Twenty years of needs analyses: reflections on a personal journey George Braine 13. The curriculum renewal process in English for academic purposes programs Fredricka L. Stoller 14. Team teaching in EAP: Changes and adaptations in the Birmingham approach Tony Dudley-Evans 15. Does the Emperor have no clothes? A re-examination of grammar in content-based instruction Donna M. Brinton and Christine A. Holten 16. The specialised vocabulary of English for academic purposes Averil Coxhead and Paul Nation 17. Language learning strategies and EAP proficiency: Teacher views, student views, and test results Matthew Peacock 18. Issues in EAP test development: What one institution and its history tell us Fred Davidson and Yeonsuk Cho 19. Teaching writing for academic purposes Dana R. Ferris 20. Reading academic English: Carrying learners across the lexical threshold Tom Cobb and Marlise Horst 21. Incorporating reading into EAP writing courses Alan Hirvela 22. The development of EAP oral discussion ability Peter Robinson, Gregory Strong, Jennifer Whittle, and Shuichi Nobe 23. Second language lecture comprehension research in naturalistic controlled conditions Steve Tauroza 24. Designing tasks for developing study competence and study skills in English Alan Waters and Mary Waters 25. Promoting EAP learner autonomy in a second language University context Tony Lynch References Index.

Inducing Human Capital Formation: Migration as a Substitute for Subsidies

Abstract: When productivity is fostered by an individual's own human capital as well as by the economy-wide average level of human capital, individuals under-invest in human capital. The provision of subsidies for the formation of human capital, conditional on the subsidy being self-financed by tax revenues, can bring the economy to its socially optimal level of human capital. Yet a strictly positive probability of migration to a richer country, by raising both the level of human capital formed by optimizing individuals in the home country and the average level of human capital of non-migrants in the country, can enhance welfare and nudge the economy toward the social optimum. Indeed, under a well-controlled, restrictive migration policy the welfare of all workers is higher than in the absence of this policy.

Design and Build Project Success Factors: Multivariate Analysis

Abstract: This study aimed to identify a set of project success factors for design and build (D&B) projects and examine the relative importance of these factors on project outcome. Six project success factors (project team commitment, contractor's competencies, risk and liability assessment, client's competencies, end-users' needs, and constraints imposed by end-users) were extracted from factor analysis of data provided by 53 participants of public-sector D&B projects through a questionnaire survey. Project team commitment, client's competencies, and contractor's competencies were found to be important to bring successful project outcome from the multiple regression findings. Contractor's competencies also contributed to project time performance. Project team members should also recognize that time and cost performance as well as quality of design and workmanship represent the key elements of overall success of D&B projects. Practitioners are advised to focus on teamwork and partnering for successful project compl...

Attitudes of Journal Editors to Nonnative Speaker Contributions

Abstract: More and more nonnative speakers (NNSs) are seeking to publish in international journals devoted to English language teaching and applied linguistics. Strong anecdotal evidence and occasional references in the literature attest to the disadvantages NNSs encounter vis-a-vis their native speaker (NS) peers. This article presents the results of an interview study with the editors of 12 leading international journals in applied linguistics and English language teaching. The purpose was to find out how these editors viewed the issue of NNSs publishing in their journals and to gain insight into how to enhance the chances of successful publication by NNSs. The results of the interviews included a questioning of the concept of the term nonnative speaker, the overall attitudes of editors and reviewers to NNS contributions, problematic aspects of NNS contributions, and positive attributes of NNS contributors. Problematic aspects included surface errors, parochialism, absence of authorial voice, and nativized varieties of English. Positive attributes include awareness of cross-linguistic and cross-cultural issues, objectivity of outsider perspectives, an international perspective, a testing mechanism for the dominant theories of the centre, access to research sites and data where NSs would be intrusive, and the alerting of centre scholars to research undertaken on the periphery.

Fuzzy wavelet networks for function learning

Abstract: Inspired by the theory of multiresolution analysis (MRA) of wavelet transforms and fuzzy concepts, a fuzzy wavelet network (FWN) is proposed for approximating arbitrary nonlinear functions. The FWN consists of a set of fuzzy rules. Each rule corresponding to a sub-wavelet neural network (WNN) consists of single-scaling wavelets. Through efficient bases selection, the dimension of the approximated function does not cause the bottleneck for constructing FWN. Especially, by learning the translation parameters of the wavelets and adjusting the shape of membership functions, the model accuracy and the generalization capability of the FWN can be remarkably improved. Furthermore, an algorithm for constructing and training the fuzzy wavelet networks is proposed. Simulation examples are also given to illustrate the effectiveness of the method.

Generation of n-scroll attractors via sine function

Abstract: A new approach for generating n-scroll attractors is introduced. It is demonstrated that n-scroll attractors can be generated using a simple sine or cosine function. A guideline is given so that a different number of scrolls can be designed easily by modifying two variables in the function. An electronic circuit is also designed for the implementation and the observation of a 9-scroll attractor is reported for the first time.

Five unique compounds: xyloketals from mangrove fungus Xylaria sp. from the South China Sea coast.

Abstract: Five unique metabolites, xyloketals A (1), B (2), C (3), D (4), and E (5), and the known 6 were isolated from mangrove fungus Xylaria sp. (no. 2508), obtained from the South China Sea. The structures of these compounds were elucidated by spectroscopic and X-ray diffraction experiments. Xyloketal A is a ketal compound with a C3 symmetry and xyloketals B−E are its analogues. It was found that xytoketal C slowly rearranged to xytoketal B in DMSO-d6 solution at room temperature. Xyloketal A exhibited the activity of inhibiting acetylcholine esterase.

Bringing in the Reader Addressee Features in Academic Articles

Abstract: Much of the literature concerning participant relationships in academic writing has discussed features that project the stance, identity, or credibility of the writer, rather than examining how writers engage with readers. In contrast, this article focuses on strategies that presuppose the active role of addressees, examining six key ways that writers seek explicitly to establish the presence of their readers in the discourse. Based on an analysis of 240 published research articles from eight disciplines and insider informant interviews, the author examines the dialogic nature of persuasion in research writing through the ways writers (a) address readers directly using inclusive or second person pronouns and interjections and (b) position them with questions, directives, and references to shared knowledge. The analysis underlines the importance of audience engagement in academic argument and provides insights into how the discoursal preferences of disciplinary communities rhetorically construct readers.

Trust in Internet Shopping: Instrument Development and Validation through Classical and Modern Approaches

Abstract: Despite the phenomenal growth of Internet users in recent years, the penetration rate of Internet shopping is still low and one of the most often cited reasons is the lack of consumers’ trust (e.g. Hoffman et al., 1999). Although trust is an important concept in Internet shopping, there is a paucity of theory-guided empirical research in this area. In this paper, a theoretical model is proposed for investigating the nature of trust in the specific context of Internet shopping. In this model, consumers’ trust in Internet shopping is affected by propensity to trust and two groups of antecedent factors, namely, "trustworthiness of Internet vendors" and "external environment". Trust, in turn, reduces consumers’ perceived risk in Internet shopping. As an important step towards the rigorous testing of the model, the necessary measurement instrument has been developed with its reliability and validity empirically tested. The psychometric properties of the measurement instrument have been investigated using both a classical approach (based on Cronbach’s alpha and exploratory factor analysis) and a contemporary approach (based on structural equation modeling techniques), as a way of methods triangulation for validating instrument properties. The resulting instrument represents a rigorously developed and validated instrument for the measurement of various important trust related constructs. This research contributes to the development of trust theory in e-commerce and add to the repository of rigorous research instruments for IS survey researchers to use.

CEO Domination, Growth Opportunities, and their Impact on Audit Fees:

Abstract: This study examines the relationship between a firm's internal monitoring mechanism and its impact on the audit fee. The first hypothesis investigates whether firms with independent corporate boards (chief executive officer and chairman being separate individuals) provide a more effective internal monitoring mechanism and are thus associated with lower control risk, resulting in lower audit effort and fees as compared to nonindependent, CEO-dominated boards. The second hypothesis examines whether the effectiveness of the internal monitoring mechanism provided by independent corporate boards is independent of the firms' growth opportunities. High-growth firms are by nature more difficult to monitor due to the existence of discretionary investments and measurement problems associated with future assets. Thus, the negative association between independent corporate boards and audit fees is expected to be affected by a firm's growth. Results using 650 observations from Hong Kong companies provide support for b...