A Bimodality Test in High Dimensions

We present a test for identifying clusters in high dimensional data based on the k-means algorithm when the null hypothesis is spherical normal. We show that projection techniques used for evaluating validity of clusters may be misleading for such data. In particular, we demonstrate that increasingly well-separated clusters are identified as the dimensionality increases, when no such clusters exist. Furthermore, in a case of true bimodality, increasing the dimensionality makes identifying the correct clusters more difficult. In addition to the original conservative test, we propose a practical test with the same asymptotic behavior that performs well for a moderate number of points and moderate dimensionality. ACM Computing Classification System (1998): I.5.3.

Suboptimal Multistage Nonparametric Hypotheses Test

2000 Mathematics Subject Classification: 62L10, 62L15.

Nonparametric versus Parametric Statistical Approaches for Genetic Anticipation: The Pancreatic Cancer Case

2000 Mathematics Subject Classi cation: 62N01, 62N05, 62P10, 92D10, 92D30.

A Test of Association between Qualitative Trait and a Set of SNPs

2000 Mathematics Subject Classification: 62P10, 92D10, 92D30, 62F03

Comparing Several Methods of Discriminant Analysis on the Case of Wine Data

2000 Mathematics Subject Classification: 62H30, 62J20, 62P12, 68T99

Fractal Analysis for Cancer Research: Case Study and Simulation of Fractals

2010 Mathematics Subject Classification: 65D18.

Impact of reduced complexity inverse Volterra series transfer function-based nonlinear equalizer in coherent OFDM systems for next-generation core networks

A modern electronic nonlinearity equalizer (NLE) based on inverse Volterra series transfer function (IVSTF) with reduced complexity is applied on coherent optical orthogonal frequency-division multiplexing (CO-OFDM) signals for next-generation long- and ultra-long-haul applications. The OFDM inter-subcarrier crosstalk effects are explored thoroughly using the IVSTF-NLE and compared with the case of linear equalization (LE) for transmission distances of up to 7000 km. © 2013 IEEE.

Automated Generating of Test Units for Evaluation of Cognitive and Language Skills

Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, May, 2016

Development of a technological innovation capability assessment model:a case study of manufacturing SMEs in Sialkot, Pakistan

Small and Medium Enterprises (SMEs) play an important part in the economy of any country. Initially, a flat management hierarchy, quick response to market changes and cost competitiveness were seen as the competitive characteristics of an SME. Recently, in developed economies, technological capabilities (TCs) management- managing existing and developing or assimilating new technological capabilities for continuous process and product innovations, has become important for both large organisations and SMEs to achieve sustained competitiveness. Therefore, various technological innovation capability (TIC) models have been developed at firm level to assess firms‘ innovation capability level. These models output help policy makers and firm managers to devise policies for deepening a firm‘s technical knowledge generation, acquisition and exploitation capabilities for sustained technological competitive edge. However, in developing countries TCs management is more of TCs upgrading: acquisitions of TCs from abroad, and then assimilating, innovating and exploiting them. Most of the TIC models for developing countries delineate the level of TIC required as firms move from the acquisition to innovative level. However, these models do not provide tools for assessing the existing level of TIC of a firm and various factors affecting TIC, to help practical interventions for TCs upgrading of firms for improved or new processes and products. Recently, the Government of Pakistan (GOP) has realised the importance of TCs upgrading in SMEs-especially export-oriented, for their sustained competitiveness. The GOP has launched various initiatives with local and foreign assistance to identify ways and means of upgrading local SMEs capabilities. This research targets this gap and developed a TICs assessment model for identifying the existing level of TIC of manufacturing SMEs existing in clusters in Sialkot, Pakistan. SME executives in three different export-oriented clusters at Sialkot were interviewed to analyse technological capabilities development initiatives (CDIs) taken by them to develop and upgrade their firms‘ TCs. Data analysed at CDI, firm, cluster and cross-cluster level first helped classify interviewed firms as leader, follower and reactor, with leader firms claiming to introduce mostly new CDIs to their cluster. Second, the data analysis displayed that mostly interviewed leader firms exhibited ‗learning by interacting‘ and ‗learning by training‘ capabilities for expertise acquisition from customers and international consultants. However, these leader firms did not show much evidence of learning by using, reverse engineering and R&D capabilities, which according to the extant literature are necessary for upgrading existing TIC level and thus TCs of firm for better value-added processes and products. The research results are supported by extant literature on Sialkot clusters. Thus, in sum, a TIC assessment model was developed in this research which qualitatively identified interviewed firms‘ TIC levels, the factors affecting them, and is validated by existing literature on interviewed Sialkot clusters. Further, the research gives policy level recommendations for TIC and thus TCs upgrading at firm and cluster level for targeting better value-added markets.

Temporal and spatio-temporal regimes of generation of Raman fibre lasers

Temporal dynamics of Raman fibre lasers tend to have very complex nature, owing to great cavity lengths and high nonlinearity, being stochastic on short time scales and quasi-continuous on longer time scales. Generally fibre laser intensity dynamics is represented by one-dimensional time-series, which in case of quasi-continuous wave generation in Raman fibre lasers gives little insight into the processes underlying the operation of a laser. New methods of analysis and data representation could help to uncover the underlying physical processes, understand the dynamics or improve the performance of the system. Using intrinsic periodicity of laser radiation, one dimensional intensity time series of a Raman fibre laser was analysed over fast and slow variation time. This allowed to experimentally observe various spatio-temporal regimes of generation, such as laminar, turbulent, partial mode-lock, as well as transitions between them and identify the mechanisms responsible for the transitions. Great cavity length and high nonlinearity also make it difficult to achieve stable high repetition rate mode-locking in Raman fibre lasers. Using Faraday parametric instability in extremely simple linear cavity experimental configuration, a very high order harmonic mode-locking was achieved in ò.ò kmlong Raman fibre laser. The maximum achieved pulse repetition rate was 12 GHz, with 7.3 ps long Gaussian shaped pulses. There is a new type of random lasers – random distributed feedback Raman fibre laser, which temporal properties cannot be controlled by conventionalmode-locking or Q-switch techniques and mechanisms. By adjusting the pump configuration, a very stable pulsed operation of random distributed feedback Raman fibre laser was achieved. Pulse duration varied in the range from 50 to 200 μs depending on the pump power and the cavity length. Pulse repetition rate scaling on the parameters of the system was experimentally identified.

A lean kultúra értelmezése és mérése egy egészségügyi szolgáltatónál (The interpretation and measurement of the lean culture – in case of a healthcare service provider)

A lean menedzsment egészségügyi szolgáltatásokra való alkalmazásával elérhető eredmények egyre inkább nyilvánvalóvá válnak. Ennek köszönhetően a szektorban dinamikus növekedés tapasztalható ezen a téren. A kutatások azonban arra hívják fel a figyelmet, hogy a lean menedzsment alkalmazásával elért eredmények csak akkor lesznek fenntarthatóak, ha az eszközök alkalmazását a kultúra átalakulása is követi. A kultúra változásának követéséhez annak folyamatos értékelésére van szükség. A szervezeti kultúra lean-specifikus méréséhez azonban – a szerzők tudomása szerint – még nincs kidolgozott eszköz. Ezért cikkükben a kapcsolódó szakirodalom áttekintése után kidolgoztak egy lean kultúra kérdőívet, majd bemutatják a kérdőív tesztelését és annak eredményeit. Összegzésként elmondható, hogy az itt bemutatott kérdőív az első tesztelés alapján további fejlesztésre szorul. / === / The results that can be obtained by applying lean management in healthcare services become more and more clear. This generates a dynamic increase of lean applications in healthcare. However, researches are warning that the res ults obtained by lean applications can only be sustained, if next to the use of the lean tools cultural change will also take place. In order to track changes in culture its constant evaluation is necessary. According to the authors’ knowledge today does not exist any lean-specific culture evaluation tool. In this paper they elaborate a lean culture questionnaire based on the review of relevant literature. Than they describe its test and the results of the test. The authors conclude that the questionnaire as introduced here needs further improvement.

An asymptotic test for the Conditional Value-at-Risk

Conditional Value-at-Risk (equivalent to the Expected Shortfall, Tail Value-at-Risk and Tail Conditional Expectation in the case of continuous probability distributions) is an increasingly popular risk measure in the fields of actuarial science, banking and finance, and arguably a more suitable alternative to the currently widespread Value-at-Risk. In my paper, I present a brief literature survey, and propose a statistical test of the location of the CVaR, which may be applied by practising actuaries to test whether CVaR-based capital levels are in line with observed data. Finally, I conclude with numerical experiments and some questions for future research.

Defining failure in the nonprofit organization: The case of four human service agencies

Private nonprofit human service organizations provide a spectrum of services that aim to resolve societal problems. Their failure may leave needed and desired services unprovided or not provided sufficiently to meet public demand. However, the concept of organizational failure has not been examined for the nonprofit organization. This research addresses the deficiency in the literatures of organization failure and nonprofit organizations.^ An eight category typology, developed from a review of the current literature and findings from expert interviews, is initially presented to define nonprofit organization failure. A multiple case study design is used to test the typology in four nonprofit human service delivery agencies. The case analysis reduces the typology to five types salient to nonprofit organization failure: input failure, legitimacy failure, adaptive failure, management failure and leadership failure.^ The resulting five category typology is useful to both theory builders and nonprofit practitioners. For theory development, the interaction of the failure types extends the literature and lays a foundation for a theory of nonprofit organization failure that diffuses management and leadership across all of the failure types, highlights management and leadership failure as collective functions shared by paid staff and the volunteer board of directors, and emphasizes the importance of organization legitimacy.^ From a practical perspective, the typology provides a tool for diagnosing failure in the nonprofit organization. Using the management indicators developed for the typology, a checklist of the warning signals of potential failure, emphasizing the key types of management and leadership, offers nonprofit decision makers a priori examination of an organization's propensity for failure. ^

Planning and evaluation of Business English course in compliance with internationalization in Taiwan: A case study of Tainan Women's College of Arts & Technology

In compliance with the economic internationalization movement and the development of Asia-Pacific Regional Operation Center (APROC) in Taiwan, international business has become more and more important. To sustain favorable trade balances every year and the promotion of APROC in Taiwan, more and more talent with knowledge and skills of Business English are needed. As a consequence, it is necessary to make Business English curriculum appropriate to meet the emerging needs.^ Two groups, experimental and control, received the revised or traditional Business English course to answer the question, "Does the Business English curriculum at Tainan Woman's College of Arts & Technology (TWCAT) meet the needs of students?" Ninety-five subjects were randomly selected from the commercial departments at TWCAT and then randomly assigned to the two groups. In addition, the Business English scores of the subjects' previous semester were collected and analyzed to justify the random selection and assignment. The finding was that their initial equivalence was proved.^ A questionnaire for students and another one for the business community were administered to facilitate data collection and analysis. The results of the questionnaires were used to modify the curriculum content of Business English.^ A final-term examination was given to the subjects at the end of the pilot study of Business English in early May of 1998. The resulting scores of the examination were used to determine if there was a significant difference in learning achievement between the students of the two groups.^ Using Independent Samples Test, significant results indicated that the experimental group had higher level of learning Business English than the control group. The finding supports the hypothesis of this study.^ Recommendations based on these results are that the revised curriculum be adapted and used by TWCAT because it better meets student needs. ^

Activity streets as economic opportunity generators: Case study of the Langa Township, Cape Town, South Africa

The Republic of South Africa since the 1948 inception of Apartheid policies has experienced economic problems resulting from spatially dispersed growth. The election of President Mandela in 1994, however, eliminated the last forms of Apartheid as well as its discriminatory spatial, social, and economic policies, specially toward black Africans. In Cape Town, South Africa, several initiatives to restructure and to economically revitalize blighted and abandoned township communities, like Langa, have been instituted. One element of this strategy is the development of activity streets. The main questions asked in this study are whether activity streets are a feasible solution to the local economic problems left by the apartheid system and whether activity streets represent an economically sustainable approach to development. An analysis of a proposed activity street in Langa and its potential to generate jobs is undertaken. An Employment Generation Model used in this study shows that many of the businesses rely on the local purchasing power of the residents. Since the economic activities are mostly service oriented, a combination of manufacturing industries and institutionally implemented strategies within the township will have to be developed in order to generate sustainable employment. The result seem to indicate that, in Langa, the activity street depend very much on an increase in sales, pedestrian and vehicular traffic flow. ^