bluuebunny/crossref_metadata_2025 huggingface dataset:
The Perplexity of Dat-Nom Verbs in Icelandic
Authors: Barðdal Jóhanna
Published: September 2003

This paper presents data from Modern Icelandic of a small group of Dat-Nom verbs which select for two arguments: a Dative human argument and a Nominative stimulus. When applying independently established subjecthood tests on these arguments it turns out that both pass the tests, i.e. both arguments can behave like subjects and like objects, but not at the same time. An examination of the lexical meanings of these predicates reveals that they can be divided into the following main groups: Emotive verbs, Perception Verbs, Cognition Verbs, Verbs of Attitude and Benefactive verbs. A Construction Grammar analysis is proposed, assuming two different syntactic constructions to exist in Icelandic, i.e. a Dat-Nom construction versus a Nom-Dat construction. It is argued that the occurrence of these predicates in the two constructions follows directly from their conceptual causal structure. Furthermore, the choice of subject seems to be contextually determined, i.e. the more topical argument takes on the subject function. The relation between the two constructions, i.e. the Dat-Nom and the Nom-Dat, seems to be like the relation between an ordinary transitive construction and its topicalization construction, in that when the lower argument is “topicalized” to first position the other construction is activated, hence the ordinary topicalization construction in Icelandic is not as readily available to these verbs as the other construction is.
Sentence-Medial NP-Adjuncts in English
Authors: Haegeman Liliane
Published: September 2003

The purpose of this paper is twofold. On the one hand, I want to show that, contrary to what is sometimes claimed in the literature, NP-adjuncts of the kindtomorrow, last week, etc., are attested sentence-medially in English. This pattern would seem to be particularly frequent in journalistic prose. Second, I examine and refute an analysis which takes such sentence-medial NP-adjuncts to be analysed as IP-external adjuncts across which the subject has been topicalised or focalised. Though such an analysis would be in keeping with the often proposed view that NP-adjuncts do not occupy an IP-internal position, I show that it raises a host of empirical problems and that it is not tenable. The conclusion is that NP-adjuncts cannot be analysed as being IP-external and that they occupy a high IP-internal position.
Three Perspectives on Swedish Indefinite Determiners
Authors: Nivre Joakim
Published: September 2003

This article investigates the meaning and use of singular indefinite determiners in Swedish, in particular the way in which the existential determinernågon/någotcontrasts with the indefinite articleen/ettin different contexts. The problem is approached from three different perspectives, the first being a contrastive Scandinavian perspective, where the Swedish data are reviewed in the light of contrastive data from the closely related languages Danish and Norwegian. Secondly, corpus data are used to substantiate the results of the contrastive analysis both quantitatively and qualitatively. The last section adopts a more theoretical perspective and tries to present a formal semantic analysis of the two determiners under study, drawing on typological work on indefinites and studies of the historical development of indefinite determiners.
Norwegian “Bokmål”: Present, Past and Future
Authors: Papazian Eric
Published: September 2003

The article presents the Norwegian majority official standard language “Bokmål” – its history, its present status and especially its present development – both to readers who are acquainted with the subject and to readers who are not. Some controversial aspects of Bokmål are discussed, such as its differentvarieties, itsdelimitation, especially with respect to the private standard “Riksmål”, itsoriginand the question of to what extent there is aspokenBokmål. In connection with the delimitation of Bokmål, the article introduces the distinction between “prescribed” and “factual” norms – and the norm concept itself – and argues for the necessity of distinguishing clearly between the prescribed and the factual Bokmål. The last part of the article is devoted to the present development of Bokmål, both as it is regulated and as it is practised. The latest official reforms which have been proposed are reviewed and discussed. The language policy of the main newspapers are reviewed, as is the use of Bokmål, in the press as well as in the literature.
Phenomenological Turbulence and Innovation in Knowledge Systems
Authors: Hearn Greg , Rooney David , Mandeville Thomas
Published: September 2003

Most considerations of knowledge management focus on corporations and, until recently, considered knowledge to be objective, stable, and asocial. In this paper we wish to move the focus away from corporations, and examine knowledge and national innovation systems. We argue that the knowledge systems in which innovation takes place are phenomenologically turbulent, a state not made explicit in the change, innovation and socio-economic studies of knowledge literature, and that this omission poses a serious limitation to the successful analysis of innovation and knowledge systems. To address this lack we suggest that three evolutionary processes must be considered: self-referencing, self-transformation and self-organisation. These processes, acting simultaneously, enable system cohesion, radical innovation and adaptation. More specifically, we argue that in knowledge-based economies the high levels of phenomenological turbulence drives these processes. Finally, we spell out important policy principles that derive from these processes.
Small Antennas for Wireless Micro‐Systems
Authors: Wansch Rainer
Published: September 2003

This paper will describe the topology of wireless micro‐systems networks and some of their key components. In particular we will deal with the antennas: loops, helices, F‐antennas, patches and dielectrically loaded antennas.
X‐Band MMIC Active Mixers
Authors: Tsenes Ptros S. , Stratakos Giorgos E. , Uzunoglu Nikolaos K.
Published: September 2003

In this paper two active MMIC mixers for RF front‐end applications are described. A down‐converter that converts an RF signal (fRF = 10.45 GHz) into an IF signal (fIF = 0.95 GHz)
using an LO signal (fLO = 9.5 GHz)
and an up‐converter that performs the opposite process have been fabricated. The down‐converter is designed using the topology of a dual‐gate pHEMT, while the up‐converter is implemented in the form of a double balanced mixer using the topology of the Gilbert cell and the occupied areas are approximately 0.78 mm2
and 3.86 mm2 ,
respectively. Both mixers present conversion gain, very low input and output return losses, very good isolation between all of their ports and the required LO power is quite low, while the up‐converter contains on chip, except for the dc‐bias and matching sub‐circuits, the required LO and RF baluns. Both circuits have been fabricated using the H‐40 process of GEC‐Marconi. Section 1 presents fundamentals on mixer theory and mixer design while in Section 2 the characteristics of H‐40 process are described. In Section 3 and in Section 4 the
designing, the simulated and the measured results of the down‐converter and the up‐converter are presented, respectively.
Silicon Micromachining for High Performance Passive Structures at W Band
Authors: Guillon B. , Grenier K. , Parra T. , Pons P. , Cros D. , Blondy P. , Graffeuil J. , Cazaux J. L. , Plana R.
Published: September 2003

This paper presents a micromachined technology allowing the realization of very high aspect ratio millimeter‐wave circuits. Appropriate 3D electromagnetic simulations based on the finite element method have been implemented to design the circuits. Coplanar transmission lines featuring loss level in the 2 dB range up to 105 GHz have been realized. An original silicon micromachined cavity using the whispering gallery modes properties has been
realized achieving a quality factor close to 10,000 range at 95 GHz.
Material Characterization of High Dielectric Constant Polymer–CeramicComposite for Embedded Capacitor to RF Application
Authors: Rao Yang , Yue Jireh , Wong C. P.
Published: September 2003

Embedded capacitor technology can improve electrical performance and reduce assembly cost compared with traditional discrete capacitor technology. Polymer–ceramic composites have been of great interest as embedded capacitor material because they combine the processability of polymers with the desired electrical properties of ceramics. A novel nano‐structure polymer–ceramic composite with very high dielectric constant (εr ~ 150 , a new record for the highest reported εr
value of nano‐composite) has been developed in our previous work. RF
application of embedded capacitors requires that insulating material have high dielectric constant at high frequency (GHz), low leakage current, high breakdown voltage and high reliability. A set of electrical tests have been conducted in this work to characterize the properties of the in house developed novel high dielectric constant polymer–ceramic nano‐composite. Results show that this material has faily high dielectric constant in
the RF range, low electrical leakage and high breakdown voltage. 85/85 TH aging test has been performed and it had shown this novel high K material has good reliability. An embedded capacitor prototype with capacitance density of 35 nF/cm2
has been manufactured using this nano‐composite with spinning coating technology. This
novel nano‐composite can be used for the integral capacitors in the RF applications.
Development of Broadband Low Actuation Voltage RF MEM Switches
Authors: Shen S. C. , Becher D. , Fan Z. , Caruth D. , Feng Milton
Published: September 2003

Low insertion loss, high isolation RF MEM switches have been thought of as one of the most attractive devices for space‐based reconfigurable antenna and integrated circuit applications. Many RF MEMS switch topologies have been reported and they all show superior RF characteristics compared to semiconductor‐based counterparts. At the University of Illinois, we developed state‐of‐the‐art broadband low‐voltage RF MEM switches using
cantilever and hinged topologies. We demonstrated promising sub-10 volts operation for both switch topologies.The switches have an insertion loss of less than 0:1 dB, and an isolation of better than 25 dB over the frequency range from 0.25 to 40 GHz. The RF Model of the MEM switch was also established. The low voltage RF MEM switches will provide a solution for low voltage and highly linear switching methods for the next generation of
broadband RF, microwave, and millimeter‐wave circuits.
New Niobium Capacitors with Stable Electrical Parameters
Authors: Zillgen H. , Stenzel M. , Lohwasser W.
Published: September 2003

The replacement of the anode material in tantalum capacitors by a new generation of high CV niobium powders offers the possibility to get an economical alternative to tantalum for a wide range of applications. Due to the high CV potential of niobium powder there is also an alternative to low voltage aluminum electrolytic capacitors. We developed a new niobium capacitor which shows stable electrical values. By optimizing the structure of the
dielectric and the cathodic layers as well as the process parameters we gained a capacitor which can be used up to 105 °C
. Electrical characteristics and lifetest behavior of niobium capacitors out of 100 k–150 k CV/g powder will be discussed.
Low Frequency Noise of Tantalum Capacitors
Authors: Sikula J. , Hlavka J. , Pavelka J. , Sedlakova V. , Grmela L. , Tacano M. , Hashiguchi S.
Published: September 2003

A low frequency noise and charge carriers transport mechanism analysis was performed on tantalum capacitors in order to characterise their quality and reliability. The model of Ta − Ta2O5 − MnO2
MIS structure was used to give physical interpretation of VA characteristic both in normal and reverse modes. The self‐healing process based on the high temperature MnO2 − Mn2O3
transformation was studied and its kinetic determined on the basis of noise
spectral density changes. The correlation between leakage current and noise spectral density was evaluated and noise reliability indicator was suggested. In normal mode the noise spectral density at rated voltage increases with second power of current and it varies within two decades for given leakage current value. In reverse mode there is only weak correlation and for given applied voltage, the leakage current for all ensemble varies only by one order, whereas the noise spectral density of the same samples spread in five orders.
Development of Nano Metal Powders for Ultra‐Low Fire MLC Inner Electrodes
Authors: de la Vega Fernando , Mtzner Eynat , Khasin Erik , Naor Aharon , Greenshpan Asaf
Published: September 2003

The need to reduce metal content, especially Palladium content in the multi layer ceramic components is driven by two motives. The first is the need to reduce material costs which has become a major issue due to the sharp rise and instability of palladium price. The second motive is the need to build components with ever‐growing number of
layers, in order to achieve better performance.

In this paper, a series of new metal powders, which were developed by NanoPowders Industries (NPI), will be discussed. These powders vary in composition, from pure silver, to silver–palladium, silver–platinum and silver–gold alloys. These powders are of very fine particle size. They open a broad working window for MLC design.

The different properties of the powders will be discussed in this paper, including melting and sintering behavior.
70%Ag 30%Pd Coated BaTiO3 Powder for Internal Electrode Applications
Authors: Stephenson R. C. , Peng Juin-wei
Published: September 2003

Recent trends in the electronic passive component manufacturing industry have been to eliminate or reduce reliance of pure Pd and high palladium contained Ag/Pd electrodes by substituting nickel or significantly lowers palladium content in Ag/Pd alloys. The conversion to base metal technology represents a substantial capital expense; the resistance to replace traditional air‐fired kilns to nitrogen or reducing atmosphere kilns has created the need for
new low cost air fired electrode technology. This paper presents a new electrode technology incorporating a uniform, continually coated AgPd over engineered dielectric particles. The resulting powder greatly reduces the consumption of precious metal, and provides superior thermal mechanical properties. This is achieved by matching the core ceramic structure of the powder to the manufacturer′s dielectric, thereby controlling shrinkage while maintaining desired electrical properties.
A Complication of Negative Resistance Circuits Generated by Two Novel Algorithms
Authors: Kumar Umesh
Published: September 2003

There are two algorithms to generate a negative‐resistance device which exhibits either a type‐N shaped V‐1 characteristic similar to a tunnel diode, or a type‐S shaped V‐1 characteristic similar to a four layered pnpn diode. We present here a selection of these circuits using bipolar, JFET or MOSFET or their combinations.
A New Junction Parameters Determination Using the Double Exponential Model
Authors: Dib S. , Khoury A. , PéLanchon F. , Mialhe P.
Published: September 2003

A double exponential model is used to characterize the junction properties of microelectronic devices. A method is developed to extract the physical junction parameters from the current‐voltage characteristics. The influence of the start values used for the computing processes are considered and the accuracy is discussed from results of simulated extractions. An experimental test considers the emitter‐base junction of bipolar transistors.
Negative Differential Resistance Behavior in Delta‐Doped AlInP Structure Grown by MOCVD
Authors: Yarn K. F.
Published: September 2003

An AlInP delta‐doped schottky diode exhibiting negative differential resistance (NDR)
behavior is demonstrated for the first time. The NDR characteristics with a peak to valley ratio of 5.5 and peak current density of 1KA/cm2
were
achieved at room temperature. In addition, the maximum available power is estimated up to 5W/cm2
. The mechanism for such performance is phenomenologically analyzed by the combination of resonant interband tunneling (RIT) and thermionic emission processes associated with tunneling effect on the metal‐semiconductor (MS) interface.
Non‐Linear Characterization of Memoryless SSP Amplifiers
Authors: Ali N. T.
Published: September 2003

This paper describes a testbed, which is able to generate all of the standard test signals used for characterising nonlinear amplifiers. The testbed is shown to be sufficiently linear to avoid any possible masking of the non‐linear effects of the amplifier under test. All the standard tests: single‐carrier, two‐carrier, multi‐carrier and NPR are applied to a laboratory amplifier and their results found to be in reasonably good agreement with the most popular prediction techniques. The merits of the individual test have been highlighted.
MOCVD‐Grown InGa/GaAs Emitter Delta Doping Heterojunction Bipolar Transistors
Authors: Yarn K. F.
Published: September 2003

The influence of delta doping sheet at base‐emitter (BE) junction for an InGaP/GaAs heterojunction bipolar transistor (HBT) with a 75Å undoped spacer layer is investigated. A common emitter current gain of 235, an offset voltage as small as 50mV and an Ic ideal factor of 1.01 are obtained, respectively. The use of delta doping sheet at BE junction results in a high gain and low offset voltage HBT. The improvement of current gain and offset voltage may be attributed to the reduction of BE potential spike by introducing a delta doping layer even
without the BE junction passivation.
Analysis and Simulation of Functional Stress Degradation on VDOMS Power Transistors
Authors: Zoaeter M. , Beydoun B. , Hajjar M. , Debs M. , Charles J-P
Published: September 2003

The use of VDMOS transistor under certain functional stress conditions produces a modification of its physical and electrical properties. This paper explores the physical analysis and SPICE simulation of the degradation effects related to the component micronic structure, and points out the degraded parameters following this stress.
Generalised Impedance Converters with only Transconductance Elements and Grounded Capacitors
Authors: Khan Iqbal A. , Ahmed Muslim T. , Minhaj Nigar
Published: September 2003

Novel generalised impedance converters are presented, which use only transconductance elements and/or grounded capacitors for the realisation of a wide variety of immittance functions. The generalised impedance converters can be used in the realisation of low sensitivity continuous time filters. The use of transconductance elements and grounded
capacitors in the realisation of continuous time filters lend to electronic tunability and compatibility to integration in contemporary IC technologies. The generalised impedance converters are also verified using PSPICE‐based simulation.
A Tunable Quadrature Oscillator with Only TransconductanceElements and Grounded Capacitors
Authors: Khan Iqbal A. , Ahmed Muslim T. , Minhaj Nigar
Published: September 2003

A novel quadrature oscillator is realised with only transconductance elements (TEs) and grounded capacitors. The realised quadrature oscillator uses only two inverting and two non‐inverting transconductance elements, along with two grounded capacitors. The quadrature oscillator enjoys the attractive features of low component count, independent frequency tuning and suitability for integration in MOS technology.
Feasibility of Tunable Amplifier and Bandpass Filter for Mobile Handsets Using Active Inductor Circuits
Authors: Tellez J. Rodriguez , Ali N. T. , Majeed B.
Published: September 2003

In this paper active inductor circuits are employed to assess their suitability for providing a tuning function in GaAs MMIC circuits. The specifications for a mobile handset amplifier and a bandpass filter operating from a 3 V supply rail are used as test vehicles. The design and simulation of the circuits employs a low‐cost commercially available
low pinch‐off GaAs MESFET process. The suitability of active inductors for tuning in such applications considers issues such as frequency tuning range, noise, power consumption and stability.
Development of A General Computation Agorithm for the Analysis ofMMIC Structures Based on A Three‐Dimensional Model
Authors: Makri R. , Gargalakos M. , Uzunoglu N. K.
Published: September 2003

A generalized three‐dimensional computational numerical code is developed for Monolithic Microwave Integrated Circuit (MMIC) structures based on a full wave approach using integral equation techniques. The electromagnetic properties of the MMIC structures are calculated using a Method of Moments – Galerkin technique based on integral equations and the relevant Green function to obtain a rigorous formulation. The MMIC structures are
assumed to have an arbitrary geometry involving orthogonal parallelepiped ‘cells’, each one of which is characterized with finite permittivity and conductivity values. A novel approach is proposed to treat the incident: reflected and transmitted waves at the two microstrip lines, which stand as input and output of the circuit. Their
current distribution is also being taken into account in terms of incident, reflected and transferred waves. The derived matrix is being inverted and the obtained results are the unknown coefficients of the plane waves inside the ‘cells’ and also the reflection R and transfer T coefficients. The derived numerical results concern linear cases, while the examination of non‐linear structures have been taken into account in the analytical formulation.
An Adaptive Digital Fuzzy Architecture forApplication‐Specific Integrated Circuits
Authors: Evmorfopoulos N. E. , Avaritsiotis J. N.
Published: September 2003

A generic fuzzy logic system implementation in digital hardware is presented in this paper. The architecture developed is oriented to Application‐Specific Integrated Circuits (ASICs), and its functionality is demonstrated through a typical ASIC for a simple control application. Furthermore, a distributed adaptation scheme is proposed for real‐time environments. Performance/area tradeoffs for VLSI implementation are also discussed.
How do I know if they're cheating? Teacher strategies in an information age
Authors: Williams Sadie
Published: September 2003

While potential dishonesty among students has always been a problem at all educational levels, current trends have introduced two new elements into the situation: the growing use of assessed coursework for externally examined syllabuses, and the widespread development of information technologies. These two factors taken together have led to increased doubts about the authenticity of students' work. This article reports on research into secondary school teachers' methods of assuring verification and finds four main strategies (‘CORD’) being utilized: the development of a culture of honesty, continual observation of student work, ongoing review of intermediate drafts and face‐to‐face discussion about the work. However, not all teachers have successfully developed new strategies of assessment and it is concluded from the results of this research that there is a real need for further discussion of methods and for more openness about the issues involved.
Active citizenship in schools and the community
Authors: Lawson Helen
Published: September 2003

During the 1980s the government of the time mooted the need for active citizenship which was associated with education for citizenship. The re‐emergence of citizenship education as an important part of the curriculum has meant that notions underpinning the idea, including the meaning of active citizenship, are once again under scrutiny.This article examines different understandings of citizenship and how they give rise to different beliefs about what the rights and responsibilities of the citizen should be. It then discusses the present government's understandings of active citizenship and their intention to create a socially inclusive society, shifting from a rights‐based paradigm of citizenship to one based on mutual obligation. It concludes by examining how those intentions might translate into the school context, drawing from recent research in three secondary schools in the United Kingdom.
Neuro‐linguistic Programming and learning theory
Authors: Craft Anna
Published: September 2003

This article explores relationships between Neuro‐linguistic Programming ‐ a growing school of thought and practice ‐ and established learning theory, drawing a distinction between models, strategies and theories. Some evaluative comments are made about the coherence of Neuro‐linguistic Programming as it currently stands, both in terms of its internal consistency, and in relation to established learning theories. In relation to its internal structure, questions are asked as to how far copying an expert's behaviour can really lead a learner to becoming an expert, and about the lack of attention within the theory given to the domain of application. Two other important areas are examined: the dissonance between the claim that Neuro‐linguistic Programming caters to individuality in learning while also proposing a view that learning is best done experientially; and a specific aspect of the theory, named the ‘logical levels’, asking whether learners are really as predictable and as subject to cause/effect as this theory would suggest. Finally,the epistemological basis of Neurolinguistic Programming is questioned. It is argued that, though Neuro‐linguistic Programming has begun to make an impact in education, it remains a set of strategies rather than a theory or a model, and these internal inconsistencies need to be addressed if it is to have a place among the dominant learning theories of our age.
Staff involvement in the design of a key skills curriculum model: a case‐study
Authors: Kelly Anthony , West Mel , Dee Lesley
Published: September 2003

This case‐study follows a school as it struggles to prepare for the changes brought about by Curriculum 2000 and the new key skills qualification. It describes the curriculum debate within the senior management team as it balanced the conflicting needs of subject popularity and necessity. It relates how inherent structural flaws were uncovered in the proposed curriculum strategy, how this very failure was used as an opportunity to initiate staff involvement in the design of curriculum structures and how success was subsequently fashioned from the process. It is a story of failure, consideration, reflection and improvement, and offers some insight into the lessons learned by management and teaching staff as they reflect on the process of change and their own participation in it.
Academic progress in the 16–19 curriculum: some senior staff perceptions of current monitoring systems and operational procedures
Authors: Higham Jeremy , Sharp Paul , MacHin David , Wilson Michael
Published: September 2003

In outlining its programme of target‐setting for post‐16 provision in 1997, the DfEE sought to promote the monitoring of academic progress in order to raise achievement both at institutional level and also at the individual student level. This article, based on research conducted in schools and colleges in North and West Yorkshire, focuses on the latter and examines senior staff perceptions of current monitoring systems and operational procedures. The article gives an overview of the main systems used and how these are adapted to suit the circumstances of a particular institution. The authors suggest that in general the implementation of target‐setting has been viewed positively, largely due to the current flexibility for senior staff to adapt whatever system best suits their needs. It recommends that this should be seen as a strength of the current situation and that the introduction of more uniform systems should be avoided if it is at the expense of meaningful procedures adapted to local requirements.
The National Literacy Strategy: success with literacy for all?
Authors: Riley Jeni
Published: September 2003

This article discusses critically the implementation of the National Literacy Strategy (NLS). The following issues are addressed: the importance of literacy in advanced societies; increasing public concern about literacy standards in English and Welsh primary schools; the perceived need for a large‐scale intervention into the teaching of literacy from the standpoint of international comparisons and school inspection evidence. The literacy process, its complexities and controversies, are considered and critiqued, along with the extent to which the NLS is able to accommodate the implications of research findings. In conclusion, the evaluation reports on the impact of the NLS are discussed.
The history of citizenship education in England
Authors: Heater Derek
Published: September 2003

The publication of the Crick report (1998) on citizenship education and the subsequent Order for implementing the compulsory status of the topic for Key Stages 3 and 4 have generated considerable comment. However, the historical background to this development has been only sketchily treated. This article attempts to provide a little more detail, to suggest a framework of analysis to illuminate the history and to indicate the relevance of this past experience for current work. The analytical framework is provided by the identification of five factors that have shaped the evolution of citizenship education in England. These are: the lack of central guidance and reliance on private initiatives; the extension of the franchise and the issue of maturity; social class and examination structures; war and peace; Empire and Commonwealth.
Curriculum development for professional ethics in Australian human service university programmes
Authors: Fox Tricia , Lonne Bob , McDonald Catherine
Published: September 2003

Australian academics and practitioners in the human services are particularly susceptible to social, political and economic influences in respect of their relevance, viability and operations. In fact, it can be argued that the impact of these influences has placed human service practitioners and academics in a perpetual state of vulnerability. Australian universities have been challenged to make their programmes more relevant and viable to the community at large, and practitioners face increasing workloads with limited resources based on restricted fiscal allocation, and the changing relationship between government and service providers. Drawing on interview data from twenty‐one (n = 21) practitioners, this article highlights their identified problems regarding the notion of professionalism in the human services with a particular focus on ethical dilemmas in human service practice. Gleaning these details will be a basis for recommending necessary professionalethics curricula content in human services programmes offered in Australian universities. Moreover, while the research data is Australian based, the authors contend that the universal theories and principles underpinning human service practice justify the significance and value of the data as an important source for international consideration in curriculum development of human service academic programmes.
Exploring difficulties in learning to teach English post‐16
Authors: Butcher John
Published: September 2003

This article investigates the experiences and training needs of student teachers as they learn to teach post‐16 English on a secondary Post Graduate Certificate in Education. A case‐study was conducted on a sample of Open University PGCE English students and mentors over a six‐month period. Five research instruments were developed and used iteratively to generate qualitative data. The study reveals significant problems, resulting in students feeling underprepared at the end of their 11–18 PGCE for the demands of post‐16 English teaching. The results illuminate the need for more effective models of learning to teach post‐16 English.
Developing narrative skills through case‐studies
Authors: Davies Peter , Bentham Jo , Cartwright Sarah , Wilson Jo
Published: September 2003

This article describes the adaptation of ‘story grammar’ to developing the subject understanding and literacy of 14–16‐year‐old students. ‘Story grammar” analyses the structure of episodes of a typical story and it was developed through research into the narrative development of younger, frequently language‐delayed, children. Reasons for expecting this story grammar to provide a helpful basis for teaching older students are summarized. An application of story grammar in teaching business studies is described through the activities designed for students and evidence from students' work. Implications for understanding of literacy in a subject context are discussed.
Systems approach to modeling the Token Bucket algorithm incomputer networks
Authors: Ahmed N. U. , Wang Qun , Barbosa L. Orozco
Published: September 2003

In this paper, we construct a new dynamic model for the Token Bucket (TB) algorithm used in computer networks and use systems approach for its analysis. This model is then augmented by adding a dynamic model for a multiplexor at an access node where the TB exercises a policing function. In the model, traffic policing, multiplexing and network utilization are formally defined. Based on the model, we study such issues as (quality of service) QoS, traffic sizing and network dimensioning. Also we propose an algorithm using feedback control to improve QoS and network utilization. Applying MPEG video traces as the input traffic to the model, we verify the usefulness and effectiveness of our model.
A stochastic formulation of the Bass model of new‐productdiffusion
Authors: Niu Shun-Chen
Published: September 2003

For a large variety of new products, the Bass Model (BM) describes the empirical cumulative‐adoptions curve extremely well. The BM postulates that the trajectory of cumulative adoptions of a new product follows a deterministic function whose instantaneous growth rate depends on two parameters, one of which captures an individual′s intrinsic tendency to purchase, independent of the number of previous adopters, and the other captures a positive force of influence on an individual by previous adopters. In this paper, we formulate a stochastic version of the BM, which we call the Stochastic Bass Model (SBM), where the trajectory of cumulative number of adoptions is governed by a pure birth process. We show that with an appropriately‐chosen set of birth rates, the fractions of individuals who have adopted the product by time t in a family of SBMs indexed by the size of the target population converge in probability to the deterministic fraction in a corresponding BM, when the population size approaches infinity. The formulation therefore supports and expands the BM by allowing stochastic trajectories.
Stability of time‐delay systems via Lyapunov functions
Authors: Alastruey Carlos F. , de la Sen Manuel
Published: September 2003

In this paper, a Lyapunov function candidate is introduced for multivariable systems with inner delays, without assuming a priori stability for the nondelayed subsystem. By using this Lyapunov function, a controller is deduced. Such a controller utilizes an input–output description of the original system, a circumstance that facilitates practical applications of the proposed approach.
Observability conditions of linear time‐varying systems and itscomputational complexity aspects
Authors: Starkov Konstantin E.
Published: September 2003

We propose necessary and sufficient Observability conditions for linear time‐varying systems with coefficients being time polynomials. These conditions are deduced from the Gabrielov–Khovansky theorem on multiplicity of a zero of a Noetherian function and the Wei–Norman formula for the representation of a solution of a linear time‐varying system as a product of matrix exponentials. We define a Noetherian chain consisted of some finite number of usual exponentials corresponding to this system. Our results are formulated in terms of a Noetherian chain generated by these exponential functions and an upper bound of multiplicity of zero of one locally analytic function which is defined with help of the Wei–Norman formula. Relations with Observability conditions of bilinear systems are discussed. The case of two‐dimensional systems is examined.
Robust stochastic maximum principle: Complete proof anddiscussions
Authors: Poznyak Alex S.
Published: September 2003

This paper develops a version of Robust Stochastic Maximum Principle (RSMP) applied to the Minimax Mayer Problem formulated for stochastic differential equations with the control‐dependent diffusion term. The parametric families of first and second order adjoint stochastic processes are introduced to construct the corresponding Hamiltonian formalism. The Hamiltonian function used for the construction of the robust optimal control is shown to be equal to the Lebesque integral over a parametric set of the standard stochastic Hamiltonians corresponding to a fixed value of the uncertain parameter. The paper deals with a cost function given at finite horizon and containing the mathematical expectation of a terminal term. A terminal condition, covered by a vector function, is also considered. The optimal control strategies, adapted for available information, for the wide class of uncertain systems given by an stochastic differential equation with unknown parameters from a given compact set, are constructed. This problem
belongs to the class of minimax stochastic optimization problems. The proof is based on the recent results obtained for Minimax Mayer Problem with a finite uncertainty set [14,43‐45] as well as on the variation results of [53] derived for Stochastic Maximum Principle for nonlinear stochastic systems under complete information. The corresponding discussion of the obtain results concludes this study.
Higher‐order techniques for some problems of nonlinear control
Authors: Sarychev Andrey V.
Published: September 2003

A natural first step when dealing with a nonlinear problem is an application of some version of linearization principle. This includes the well known linearization principles for controllability, observability and stability and also first‐order optimality conditions such as Lagrange multipliers rule or Pontryagin′s maximum principle. In many interesting and important problems of nonlinear control the linearization principle fails to provide a solution. In the present paper we provide some examples of how higher‐order methods of differential geometric control theory can be used for the study nonlinear control systems in such cases. The presentation includes: nonlinear systems with impulsive and distribution‐like inputs; second‐order optimality conditions for bang–bang extremals of optimal control problems; methods of high‐order averaging for studying stability and stabilization of time‐variant control systems.
Asymptotic expansions for large closed and loss queueing networks
Authors: Kogan Yaakov
Published: September 2003

Loss and closed queueing network models have long been of interest to telephone and computer engineers and becoming increasingly important as models of data transmission networks. This paper describes a uniform approach that has been developed during the last decade for asymptotic analysis of large capacity networks with product form of the stationary probability distribution. Such a distribution has an explicit form up to the normalization constant, or the partition function. The approach is based on representing the partition function as a contour integral in complex space and evaluating the integral using the saddle point method and theory of residues. This paper provides an introduction to the area and a review of recent work.
Clustering analysis and decision‐making by “rank of links”
Authors: Verulava O. , Khurodze R.
Published: September 2003

In this paper, formalism for cluster analysis, based on the “Rank of Links”‐theory, is suggested. It tackles resemble measures, cross‐distance matrices, “rank of links”‐metric and some other cluster characteristics. Using these notions, an algorithm of clustering has been designed. Its application to estimation and prognosis of decision‐making process shows nice workability and reliability.
Combinatorial problem arising in chaotic control
Authors: Bondarenko V. A. , Mustard J. , Pokrovskii A. V.
Published: September 2003

An optimization problem arising in the analysis of controllability and stabilization of cycles in discrete time chaotic systems is considered.
Robust block decomposition sliding mode control design
Authors: Loukianov Alexander G.
Published: September 2003

The paper examines the problem of sliding mode manifold design for uncertain nonlinear system with discontinuous control. The original plant first is decomposed such that the problem is divided into a number of simpler sub‐problems. Then the block control recursive procedure is presented in which nonlinear sliding manifold is derived. Finally combined high gain and Lyapunov functions techniques are applied to establish hierarchy of the control gains and to estimate the upper bounds of the sliding mode equation solutions.
Early Steps of a Thymic Tumor in SV40 Transgenic Mice: Hyperplasia of Medullary Epithelial Cells and Increased Mature Thymocyte Numbers Disturb Thymic Export
Authors: Nabarra Bernadette , Martinon Catherine , Godard Cécile , Vasseur Florence , de Ribains Geoffroy , Miquerol Lucile , Kahn Axel , Ezine Sophie
Published: September 2003

Bone marrow progenitors migrate to the thymus, where they proliferate and differentiate into immunologically competent T cells. In this report we show that mice transgenic for SV40 T and t antigens under the control of the L‐pyruvate kinase promoter develop, in a first step, thymic hyperplasia of both thymocytes and epithelial cells. Morphological studies (histology, immunohistolabeling and electron microscopy) revealed modifications of the thymic microenvironment and gradual expansion of medullary epithelial cells in 1 month‐old mice, taking over the cortical region. Then, a thymic carcinoma develops. Two‐color labeling of frozen sections identified the transgene in medullary epithelial cells. Flow cytometry analysis demonstrated a marked increase in mature CD4+ and CD8+ thymocytes in adult mice (39±10×106 in transgenic mice and 12±5×106 in age‐matched controls). Furthermore, thymocyte export was disturbed.
The Dynamics of Germinal Centre Selection as Measured by Graph‐Theoretical Analysis of Mutational Lineage Trees
Authors: Dunn-Walters Deborah K. , Belelovsky Alex , Edelman Hanna , Banerjee Monica , Mehr Ramit
Published: September 2003

We have developed a rigorous graph‐theoretical algorithm for quantifying the shape properties of mutational lineage trees. We show that information about the dynamics of hypermutation and antigen‐driven clonal selection during the humoral immune response is contained in the shape of mutational lineage trees deduced from the responding clones. Age and tissue related differences in the selection process can be studied using this method. Thus, tree shape analysis can be used as a means of elucidating humoral immune response dynamics in various situations.
Do Bovine Lymphocytes Express a Peculiar Prion Protein?
Authors: Mélot France , Thielen Caroline , Labiet Thouraya , Eisher Sabine , Jolois Olivier , Heinen Ernst , Antoine Nadine
Published: September 2003

The cellular prion protein (PrPc) is a glycolipid‐anchored cell surface protein that usually exhibits three glycosylation states. Its post‐translationally modified isoform, PrPsc, is involved in the pathogenesis of various transmissible spongiform encephalopathies (TSEs). In bovine species, BSE infectivity appears to be restricted to the central nervous system; few or no detectable infectivity is found in lymphoid tissues in contrast to scrapie or variant CJD. Since expression of PrPc is a prerequisite for prion replication, we have investigated PrPc expression by bovine immune cells. Lymphocytes from blood and five different lymph organs were isolated from the same animal to assess intra‐ and interindividual variability of PrPc expression, considering six individuals. As shown by flow cytometry, this expression is absent or weak on granulocytes but is measurable on monocytes, B and T cells from blood and lymph organs. The activation of the bovine cells produces an upregulation of PrPc. The results of our in vitro study of PrPc biosynthesis are consistent with previous studies in other species. Interestingly, western blotting experiments showed only one form of the protein, the diglycosylated band. We propose that the glycosylation state could explain the lack of infectivity of the bovine immune cells.
Frog Oocytes: A Living Test Tube for Studies on Metabolic Regulation
Authors: Ureta Tito , Preller Ana , Kessi Eduardo
Published: September 2003

This review is intended to illustrate how live frog oocytes may be advantageously used to address the study of some problems of in vivo glucose metabolism. Glucose microinjected into the cells is preferentially committed to glycogen synthesis. We present evidence showing that both the direct and indirect pathways for polysaccharide deposition are operative in oocytes. A small amount of the injected glucose (< 5%) is released as labeled CO2 mainly through the pentose‐P pathway. Coinjection of NADP+ and glucose significantly stimulates 14CO2 production, half‐maximal stimulation being obtained at 0.13 mM. Finally, we show the use of frog oocytes to measure in vivo the control coefficient of hexokinase on glycogen synthesis and the pentose‐P pathway. A value of 0.7 was found for the control coefficient of hexokinase on glycogen synthesis, while the enzyme has no control at all over the pentose‐P pathway. Therefore, the frog oocyte may be used as a living test tube for the study of almost any metabolic process of interest.
Casein Kinase I: From Obscurity to Center Stage
Authors: Vielhaber Erica , Virshup David M.
Published: September 2003

The casein kinase I (CKI) family of protein kinases is a group of highly related, ubiquitously expressed serine/threonine kinases found in all eukaryotic organisms from protozoa to man. Recent advances in diverse fields, including developmental biology and chronobiology, have elucidated roles for CKI in regulating critical processes such as Wnt signaling, circadian rhythm, nuclear import, and Alzheimer's disease progression.
Disaccharide Modulation of the Mitochondrial Membrane Fluidity Changes Induced by the Membrane Potential
Authors: Ricchelli Fernanda , Camerin Monica , Beghetto Claudia , Crisma Marco , Moretto Vittorio , Gobbo Silvano , Salvato Benedetto , Salet Christian , Moreno Giuliana
Published: September 2003

The influence of the medium composition on the dynamic properties of mitochondrial membranes on depolarization was studied by following the fluorescence anisotropy changes of mitochondriabound 1,6‐diphenyl‐1,3,5‐hexatriene (DPH) and hematoporphyrin (HP) as reporters, respectively, of lipid and protein regions. On collapse of the potential, the membrane fluidity increased in NaCl‐, KCl‐, and monosaccharide‐based media and decreased in disaccharides. Infrared spectroscopy experiments suggested that disaccharides likely change water's structure and association on the membrane surface. These results indicate that disaccharides induce membrane perturbation, which may interfere in the study of structure‐function correlation in biological membranes.
Optical Study of Cytochrome cM Formation in Synechocystis
Authors: Shuvalov Vladimir A. , Allakhverdiev Suleyman I. , Sakamoto Atsushi , Malakhov Michael , Murata Norio
Published: September 2003

The expression of the cytM gene, which encodes cytochrome cM in Synechocystis sp. PCC 6803, is induced under stress conditions such as low temperature. Results of spectrophotometric studies revealed that cytochrome cM was oxidized by light absorbed by photosystem I in cells that had acclimatized to a low temperature. However, no similar light‐induced oxidation of cytochrome cM