bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal portion control using variable cutter‐blade spacing in can‐filling
Authors: Omar F. , de Silva C. W.
Published: August 2002

In the present context, optimal portion control refers to the process of preparing can‐filling portions so that the deviation of the portion weight from a specified target weight is minimized. An approach has been developed for achieving this where a batch of objects is placed in a linearly overlapped optimal arrangement and then cut into portions using a series of parallel blades. The parameters of optimization are the arrangement order, orientation and degree of overlap of the objects. The approach has been demonstrated to produce impressive improvements in the application of fish canning. For this application, two approaches of optimal cutting are compared in the present paper. In one approach, the blade spacing is kept fixed and constant at a predetermined value. In the second approach, the blade spacing is varied for each portion after the objects are placed according to the optimal arrangement, where the target weight distribution is allowed to vary within a tolerance interval. The results presented in this paper indicate that the second approach produces a significantly higher percentage of acceptable portions than the first approach. What is presented are results from computer simulations, utilizing true data as measured from actual batches of fish. The paper demonstrates the potential benefit of the optimal portion control approach when applied in an industrial fish‐canning process. Copyright © 2001 John Wiley & Sons, Ltd.
Exploring the suitability of the European Foundation for Quality Management (EFQM) Excellence Model as a framework for delivering clinical governance in the UK National Health Service
Authors: Jackson Sue
Published: August 2002

In December 1997 the United Kingdom (UK) government publicized its vision for the National Health Service (NHS) to become the best health care system in the world. In line with this vision a number of consultative and directive documents were circulated, one of which was Clinical Governance: in the new NHS. This particular document provided insight into the principles and proposed framework for delivering clinical governance. However, the document suggested that health care organizations create mechanisms for delivering clinical governance which implied that the government had failed to recognize that suitable mechanisms were already available. The author suggests that one such suitable mechanism/framework is the EFQM Excellence Model. The article therefore examines the similarities of the principles behind clinical governance and the EFQM Excellence Model and recommends the latter as a suitable tool for ensuring that the country's people have the best health care system in the world. Copyright © 2001 John Wiley & Sons, Ltd.
Standard operating procedures for clinical research personnel—part 6
Authors: Bohaychuk Wendy , Ball Graham
Published: August 2002

This is the sixth in a series of articles containing proposals for wording and content of standard operating procedures (SOPs) for clinical research activities conducted by sponsors and Contract Research Organisations (CROs). The procedures include those required by the International Conference on Harmonisation (ICH), the Food and Drug Administration (FDA), many other guidelines and regulations, and ‘best practice’ observed by the authors. The model forms require modification for actual use. In this article, three SOPs for the management of investigator brochures including preparation (SOP 301), review, approval and amendment (SOP 302) and distribution (SOP 303) are addressed. A sample of the format and contents of an investigator brochure is also included. (The full text of all 101 SOPs is available from the authors.) Copyright © 2001 John Wiley & Sons, Ltd.
GCP auditors: hard to find—hard to develop—hard to keep: part III. Continuous education and further development
Authors: Hattemer‐Apostel Rita
Published: August 2002

Clinical research is a dynamic and constantly changing discipline. Continuous education of good clinical practice (GCP) auditors is required to guarantee consistent and dependable audit results during their careers. Ongoing training should strive to increase the auditor's capabilities and skills, even beyond GCP. This should not only maintain the quality assurance (QA) auditor in a position to conduct audits according to state‐of‐the‐art methodologies and regulations, but also promote her/his further career development. To be ‘fit for purpose’ does not only characterize processes meeting defined requirements, but also implies that QA auditors must be continuously trained (hence, ‘be fit’) to perform high‐quality audit services (hence, ‘the purpose’). Copyright © 2001 John Wiley & Sons, Ltd.
Standard operating procedures for clinical research personnel—Part 7
Authors: Bohaychuk Wendy , Ball Graham
Published: August 2002

This is the seventh in a series of articles containing proposals for wording and content of standard operating procedures (SOPs) for clinical research activities conducted by sponsors and Contract Research Organizations (CROs). The procedures include those required by the International Conference on Harmonization (ICH), the Food and Drug Administration (FDA), many other guidelines and regulations, and ‘best practice’ observed by the authors. The model forms require modification for actual use. In this article, SOPs are presented for the management of protocols and protocol amendments including preparation and format (SOPs 304 and 307), review, approval and amendment (SOPs 305 and 308) and distribution (SOPs 306 and 309). (The full text of all 101 SOPs is available from the authors.) Copyright © 2001 John Wiley & Sons, Ltd.
Use and limitations of checklists. Other strategies for audits and inspections
Authors: Seoane Pedro J. Gris
Published: August 2002

Checklists are tools commonly used by quality assurance (QA) unit professionals in inspections and audits as they perform their customary tasks of verifying and checking compliance with various applicable standards. An analysis of the advantages and disadvantages of checklist use is discussed in this article. Excessive dependence on these auxiliary‐checking systems can cause certain problems, and in some cases their real usefulness is called into question. Alternative or complementary strategies are proposed in order to optimise the rational use of checklists. Copyright © 2001 John Wiley & Sons, Ltd.
Standard operating procedures for clinical research personnel ‐ Part 12
Authors: Bohaychuk Wendy , Ball Graham
Published: August 2002

This is the 12th in a series of articles containing proposals for wording and content of standard operating procedures (SOPs) for clinical research activities conducted by sponsors and Contract Research Organisations (CROs). The procedures include those required by the International Conference on Harmonisation (ICH), the Food and Drug Administration (FDA), many other guidelines and regulations, and 'best practice' observed by the authors. The model forms require modification for actual use. In this article, a SOP is presented for selection of clinical laboratories (SOP 327). (The full text of all 101 SOPs is available from the authors). Copyright © 2002 John Wiley & Sons, Ltd.
A forecast‐based monitoring methodology for process transitions
Authors: Nembhard Harriet Black , Kao Ming Shu
Published: August 2002

Nonconforming parts are often produced when a process moves from one level to another due to transition events. Control charting, when applied to a stable state process, is an effective monitoring tool to continuously check for process shifts or upsets. However, the presence of transition events can impede the normal performance of traditional control chart with increased false alarms. The presence of autocorrelation also requires modification to the control charting procedure. We present a methodology for characterizing the process transition which involves a tracking signal statistic, based on the forecast‐based exponentially weighted moving average (EWMA). This test will supplement the forecast‐based EWMA control charting as a means of detecting when the transition event is complete. Such a procedure facilitates smooth application of the appropriate control chart by knowing when the transition is over. The transition characterization methodology also carries benefits in cost and material savings. We use a color transition process in plastic extrusion to illustrate a transition event and demonstrate our proposed methodology. Simulation is employed to evaluate the performance of the methodology. Copyright © 2001 John Wiley & Sons, Ltd.
GRECP/5e‐MRD‐CI calculation of the electronic structure of PbH
Authors: Isaev T. A. , Mosyagin N. S. , Titov A. V. , Alekseyev A. B. , Buenker R. J.
Published: August 2002

The correlation calculation of the electronic structure of PbH is carried out with the generalized relativistic effective core potential (GRECP) and multireference single‐ and double‐excitation configuration interaction (MRD‐CI) methods. The 22‐electron GRECP for Pb is used and the outer core 5s, 5p, and 5d pseudospinors are frozen using the level‐shift technique, so only five external electrons of PbH are correlated. A new configuration selection scheme with respect to the relativistic multireference states is employed in the framework of the MRD‐CI method. The [6, 4, 3, 2] correlation spin–orbit basis set is optimized in the coupled cluster calculations on the Pb atom using a recently proposed procedure, in which functions in the spin–orbital basis set are generated from calculations of different ionic states of the Pb atom and those functions are considered optimal that provide the stationary point for some energy functional. Spectroscopic constants for the two lowest‐lying electronic states of PbH (2Π1/2, 2Π3/2) are found to be in good agreement with the experimental data. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Theoretical analysis on TiO2(110)/V surface
Authors: Sambrano J. R. , Martins J. B. L. , Andres J. , Longo Elson
Published: August 2002

Theoretical analysis based on the Hartree–Fock method were performed in order to study the stoichiometric TiO2 (110) surface and the vanadium substituted system. The Pople with polarization 3‐21G* basis set level was used. The TiO2 (110) surface was modeled using a (TiO2)15 cluster model. In order to take into account the finite size of the cluster, we have studied two different models: the point charge and the hydrogen saturated methodologies. The charge values used in the point charge calculations were optimized. The density of states, orbital self‐consistend field (SCF) energies, and Mulliken charge values were analyzed. The method and model's dependence on the analyzed results are discussed. The theoretical results are compared with available experimental data. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Gas chromatography/combustion/isotope‐ratio‐monitoring mass spectrometric analysis of methylboronic derivatives of monosaccharides: a new method for determining natural 13C abundances of carbohydrates
Authors: van Dongen Bart E. , Schouten Stefan , Damsté Jaap S. Sinninghe
Published: August 2002

Monosaccharides were derivatized using methylboronic acid and N,O‐bis(trimethylsilyl)trifluoroacetamide (BSTFA), and the δ13C values of these derivatives measured by gas chromatography/combustion/isotope‐ratio‐monitoring mass spectrometry to determine the original 13C‐content of the monosaccharides. Comparison with the measured off‐line δ13 values of the monosaccharides shows that no fractionation in 13C takes place during derivatization. The methylboronic derivatization method has proven to be a new method for natural abundance isotopic analysis of intact monosaccharides (arabinose, xylose, fucose, fructose and glucose). The method is rapid, does not involve isotopic fractionation during derivatization, and gives more precise δ13C values than other methods reported. The method was successfully applied to determine the δ13C value of glucose of the freshwater alga Scenedesmus communis. Copyright © 2001 John Wiley & Sons, Ltd.
Coupling of a supercritical fluid chromatography system to a hybrid (Q‐TOF 2) mass spectrometer: on‐line accurate mass measurements
Authors: Garzotti Marco , Rovatti Luca , Hamdan Mahmoud
Published: August 2002

This note describes a simple and economical method to couple a supercritical fluid chromatography (SFC) system (Berger Instruments, US) with a high‐resolution hybrid mass spectrometer (Q‐TOF 2; Micromass, UK). This experimental arrangement has three distinct advantages: (1) coupling between the two systems can be effected without the need for an interface or hardware modifications of either system, (ii) this experimental arrangement provides on‐line accurate mass SFC/MS measurements which are indispensable for the characterisation of new chemical entities and unknown metabolites, and (iii) the characteristically fast spectral acquisition rate of the time‐of‐flight (TOF) analyser renders the present arrangement an important contribution to future semipreparative fraction collection setups which use mass spectrometry as a detector. Copyright © 2001 John Wiley & Sons, Ltd.
Screening for anabolic steroids and related compounds in illegal cocktails by liquid chromatography/time‐of‐flight mass spectrometry and liquid chromatography/quadrupole time‐of‐flight tandem mass spectrometry with accurate mass measurement
Authors: Nielen Michel W. F. , Vissers Johannes P. C. , Fuchs Regine E. M. , Velde Jan W. van , Lommen Arjen
Published: August 2002

Findings of illegal hormone preparations such as syringes, bottles, cocktails, and so on, are an important information source for the nature of the current abuse of anabolic steroids and related compounds as growth‐promoting agents in cattle. A new screening method for steroids in cocktails is presented based on liquid chromatography (LC) with diode‐array UV‐absorbance detection and electrospray ionization time‐of‐flight mass spectrometry (ESI‐TOFMS). Accurate mass measurements were performed at a mass resolution of 4000 using continuous introduction of a lock mass through a second (electro)sprayer. Similar experiments were carried out using dual‐sprayer quadrupole time‐of‐flight mass spectrometry (ESI‐QTOFMS/MS) at a mass resolution of 10 000 with data‐dependent MS/MS acquisition; i.e. beyond an intensity threshold for the [M + H]+ ions, MS/MS spectra were automatically acquired at three different collision energies. Elemental compositions were calculated for precursor and product ions and it is shown that the combined information from LC retention behavior, UV spectra, elemental compositions, and accurate mass MS/MS spectra yield a fast impression of the steroids present in the complex mixture. Using a new software tool for structure elucidation of MS/MS spectra, an additional non‐steroidal additive was identified as well. Copyright © 2001 John Wiley & Sons, Ltd.
A combined linear ion trap time‐of‐flight system with improved performance and MSn capabilities
Authors: Collings B. A. , Campbell J. M. , Mao Dunmin , Douglas D. J.
Published: August 2002

A detailed description of a linear ion trap time‐of‐flight (TOF) mass spectrometer system, capable of sequential mass spectrometry (MSn), is given. Many improvements have been incorporated since the initial description of this system (Rapid Commun. Mass Spectrom. 1998; 12: 1463–1474). The pressure in the trap has been lowered from 7.0 to 1.8 mTorr, resulting in an increase in the mass resolution of ion excitation from 75 to 240. Use of the system for MS3 is demonstrated. Dipole excitation of the n = 1 harmonic, instead of the n = 0 fundamental frequency of ion motion, is shown to have a higher frequency resolution, f/Δf, but lower mass resolution, m/Δm. Both experiments and modeling demonstrate that at the lower pressure there is less collisional cooling of ions in the axial and radial directions of the trap. The efficiency of trapping is shown to be nearly 100% for periods up to 5 s. The demonstrated mass range for mass analysis has been extended to greater than m/z 16 250. To avoid the formation of adduct ions when trapping protein ions for extended times requires ultra‐high vacuum cleanliness conditions, even though the trap operates in the mTorr‐pressure range. Upgrading the TOF to a reflectron with higher quality ion optics results in an increase in the mass resolution of the TOF mass spectrometer to about 5000 at m/z 750. Copyright © 2001 John Wiley & Sons, Ltd.
Rapid monitoring assay of congenital adrenal hyperplasia with microbore high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry from dried blood spots
Authors: Lai Chien‐Chen , Tsai Chang‐Hai , Tsai Fuu‐Jen , Lee Cheng‐Chun , Lin Wei‐De
Published: August 2002

17‐Hydroxyprogesterone (17OHP) is the most important plasma parameter for diagnosing and monitoring congenital adrenal hyperplasia (CAH) caused by 21‐hydroxylase deficiency. A rapid, simple, and specific method based on microbore high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry (µ‐HPLC/ESI‐MS/MS) was developed to determine the presence of 17OHP on dried filter‐paper blood samples from patients with CAH caused by 21‐hydroxylase deficiency. 17OHP from dried blood spots formed by the action of Girard reagent P (GirP) turned out to be a water‐soluble hydrazone complex. Derivatization with GirP led to higher ESI sensitivity for 17OHP. The LC/MS/MS detection of GirP‐derivatized 17OHP (GirP‐17OHP) was rapid (<3 min). The method is repeatable and reproducible, with CVs <7% and 12%, respectively. This new method was used for direct determination of 17OHP in dried blood specimens obtained from abnormal children and infants of various ages with a detection limit of 10 ng/mL (∼12 µL blood). The method described allows for rapid and reliable measurements of 17OHP in dried blood specimens from patients affected by CAH. Copyright © 2001 John Wiley & Sons, Ltd.
Effects of flow rate on high‐throughput quantitative analysis of protein‐precipitated plasma using liquid chromatography/tandem mass spectrometry
Authors: Murphy Anthony T. , Berna Michael J. , Holsapple Jeffrey L. , Ackermann Bradley L.
Published: August 2002

The effects of flow rate and column length on analyte response (peak area and height), total cycle time, column backpressure, and elution volume are presented. Rapid chromatographic separations and tandem mass spectrometric (MS/MS) detection are applied to the supernatant of protein‐precipitated plasma standards containing four compounds from a drug discovery screen. The plasma samples were injected onto three C‐18 columns (2 × 10,2.1 × 30 and 2.1 × 50 mm) at flow rates of 0.25, 0.50, 1.00 and 1.50 mL/min. The plasma samples were detected using a Sciex API 3000 tandem mass spectrometer operated in the Turbo Ionspray mode. A post‐column split was used to maintain a flow rate of 0.25 mL/min into the mass spectrometer source to avoid differences in nebulization efficiency. The data show that diluted protein‐precipitated plasma supernatants show average matrix effects (i.e. suppression) of 60.0% (2 × 10 mm), 89.3% (2 × 30 mm), and 76.7% (2 × 50 mm) of expected response at 10 ng/mL. Average matrix effects of 70.2% (2 × 10 mm), 88.9% (2 × 30 mm), and 81.2% (2 × 50 mm) of expected response at 1000 ng/mL plasma. The data also show if peak widths remain relatively constant, analytes are less sensitive as flow rates are increased. These data are consistent with the concentration‐dependent relationship of ionspray in the range of flow rates studied. The data show that, while analyte response decreased proportionately to increases in flow rate, the analysis cycle times did not decrease proportionately. Copyright © 2002 John Wiley & Sons, Ltd.
Stable isotope compositions of CO2 in background air and at polluted sites in Hungary
Authors: Demény Attila , Haszpra László
Published: August 2002

CO2 samples were collected from air at three sites in Hungary for comparison of polluted and background areas. In order to reduce the uncertainties caused by the varying amount of N2O, a gas chromatography (GC)‐based vacuum separation was applied. The reliability of the procedure was demonstrated by careful standardization and comparison with global network data. The stable isotope data show complex diurnal and seasonal variations that can be explained by fractionations during photosynthesis and respiration. The isotopic characteristics of pollution‐derived (anthropogenic) and biogenic CO2 appear to be indistinguishable at the study sites. However, the sites at unpolluted areas reveal a seasonal variation in the carbon isotope composition of biogenic CO2 that may be related to changes in soil biogenic activities. The atmospheric background CO2 shows constant δ13C in the region. Finally, the study demonstrates the need for careful standardization of sampling in order to make the data obtained from different sampling systems comparable. Copyright © 2002 John Wiley & Sons, Ltd.
Methodology and model for performance and cost comparison of innovative treatment technologies at wood preserving sites
Authors: Evans Mark L. , Porges Robert E. , Coghlan Gunarti H. , Eilers Richard G. , Glazer Art G.
Published: August 2002

Wood preserving facilities have used a variety of compounds, including pentachlorophenol (PCP),
creosote, and certain metals, to extend the useful life of wood products. Past operations and waste management
practices resulted in soil and water contamination at a portion of the more than 700 wood preserving sites in the
United States (EPA, 1997). Many of these sites are currently being addressed under federal, state, or
voluntary cleanup programs. The U.S. Environmental Protection Agency (EPA) National Risk Management
Research Laboratory (NRMRL) has responded to the need for information aimed at facilitating remediation
of wood preserving sites by conducting treatability studies, issuing guidance, and preparing reports. This article
presents a practical methodology and computer model for screening the performances and comparing the costs of
seven innovative technologies that could be used for the treatment of contaminated soils at user‐specified
wood preserving sites. The model incorporates a technology screening function and a cost‐estimating
function developed from literature searches and vendor information solicited for this study. This article also
provides background information on the derivation of various assumptions and default values used in the model,
common contaminants at wood preserving sites, and recent trends in the cleanup of such sites. © 2001 John
Wiley & Sons, Inc.
Iowa's land recycling program: A case study
Authors: Quast Cynthia L.
Published: August 2002

Voluntary cleanup programs for contaminated sites have been developed in several states over the last few years.
Some of the advantages of these programs include developing a collaboration between site owners and regulators,
implementing cleanup standards based upon site‐specific current and future risks, and enhancing the market
conditions that can lead to development of properties to their highest productive use. This article offers a case
study of the first site in Iowa to proceed through the state's voluntary cleanup program, the Land Recycling
Program. It offers the step‐by‐step progress toward the client's goal of a site classification
requiring no further action. © 2001 John Wiley & Sons, Inc.
Using integrated food‐web and population‐based models for environmental monitoring, remediation decisions, and long‐term planning
Authors: Burger Joanna , Hunter John , Cooper Keith
Published: August 2002

While ecologists have used food‐web models to understand how ecosystems function, the potential role
of integrated food‐web and population‐based models in environmental monitoring and decision making
has been ignored. Sound ecological principles should be integrated with state‐of‐the‐art
monitoring and management practices. This article presents the ways in which population‐based models can
answer basic ecological questions necessary for decision making about remediation and restoration, and for
monitoring to ensure long‐term stewardship. Discussed are the uses of food‐web and
population‐based models for understanding the movement of chemicals through different trophic levels.
Three examples, including global warming, tributyltin, and monomethylmercury scenarios, are presented to
illustrate how such models are useful. The responses of the component parts varies, depending on parameters such
as birth, death, and respiration, as well as feeding rates, predator‐prey rates, and uptake and
elimination rates. There are several different models available for decision making, with different levels of
complexity, based on the specific hypothesis or question being asked and the amount of current information
available. Therefore, it is recommended to use deterministic‐based, population‐based
food‐web models for ecological risk assessment. © 2001 John Wiley & Sons, Inc.
A team algorithm for robust stability analysis and control design of uncertain time‐varying linear systems using piecewise quadratic Lyapunov functions
Authors: Almeida H. L. S. , Bhaya A. , Falcão D. M. , Kaszkurewicz E.
Published: August 2002

A team algorithm based on piecewise quadratic simultaneous Lyapunov functions for robust stability analysis and control design of uncertain time‐varying linear systems is introduced. The objective is to use robust stability criteria that are less conservative than the usual quadratic stability criterion. The use of piecewise quadratic Lyapunov functions leads to a non‐convex optimization problem, which is decomposed into a convex subproblem in a selected subset of decision variables, and a lower‐dimensional non‐convex subproblem in the remaining decision variables. A team algorithm that combines genetic algorithms (GA) for the non‐convex subproblem and interior‐point methods for the solution of linear matrix inequalities (LMI), which form the convex subproblem, is proposed. Numerical examples are given, showing the advantages of the proposed method. Copyright © 2001 John Wiley & Sons, Ltd.
Robust and non‐fragile PID controller design
Authors: Ho Ming‐Tzu , Datta Aniruddha , Bhattacharyya S. P.
Published: August 2002

This paper provides a solution to the problem ofrobustlystabilizing a given interval plant family using P, PI and PID controllers. This solution is derived by combining some recent results on P, PI and PID stabilization of fixed plants with some standard results from the parametric robust control literature. The paper also develops a technique for designing PID controllers which are not only robust with respect to plant parameter perturbations but are also ‘non‐fragile’ in the space of the controller coefficients. Copyright © 2001 John Wiley & Sons, Ltd.
Redesign of backstepping for robustness against unmodelled dynamics
Authors: Arcak Murat , Kokotovic Petar
Published: August 2002

We present a redesign method to robustify backstepping control laws against linear unmodelled dynamics at the input of the plant. The admissible unmodelled dynamics are relative degree zero and minimum phase. We prove that the redesign ensures global boundedness and convergence of the closed‐loop solutions to an arbitrarily small compact set around the origin. Copyright © 2001 John Wiley & Sons, Ltd.
Structured singular value approach for systems with parametric uncertainty
Authors: Young Peter M.
Published: August 2002

This paper provides a tutorial introduction and overview of analysis and design techniques for systems with both parametric uncertainty and unmodelled dynamics, using the structured singular value, orμ, family of techniques. This includes the analysis/design framework, stability and performance problems, frequency sweeps and state‐space tests, continuous‐time and discrete‐time systems, and computational issues and methods for both analysis and design. The paper also includes connections between the structured singular value and polynomial approaches to handling parametric uncertainty, as well as several examples which illustrate how to cast typical (including polynomial) problems into theμframework. Copyright © 2001 John Wiley & Sons, Ltd.
Robust ℋ︁∞filtering for uncertain Markovian jump linear systems
Authors: de Souza Carlos E. , Fragoso Marcelo D.
Published: August 2002

This paper investigates the problem of ℋ︁∞filtering for a class of uncertain Markovian jump linear systems. The uncertainty is assumed to be norm‐bounded and appears in all the matrices of the system state‐space model, including the coefficient matrices of the noise signals. It is also assumed that the jumping parameter is available. We develop a methodology for designing a Markovian jump linear filter that ensures a prescribed bound on the ℒ︁2‐induced gain from the noise signals to the estimation error, irrespective of the uncertainty. The proposed design is given in terms of linear matrix inequalities. Copyright © 2002 John Wiley & Sons, Ltd.
On Horowitz's contributions to reset control
Authors: Chait Yossi , Hollot C. V.
Published: August 2002

History shows that Prof. Isaac Horowitz was often ahead of the curve in his feedback control research, especially in developing quantitatively driven design procedures. In some topics, his work was so out of line with the main stream that it has received virtually no recognition from the control community until a few decades later. In this paper, we present recent research that was directly motivated by Horowitz's pioneering work on reset controllers in the 1970s. Reset controllers are linear controllers that reset some of their states to zero when their inputs reach a threshold. Horowitz motivated their use by showing that with qualitative design, they can exhibit better performance trade‐offs than those in linear, time‐invariant systems. This paper supports and advances his thinking by presenting recent theoretical and experimental results on reset control. Copyright © 2002 John Wiley & Sons, Ltd.
Interval QFT: a mathematical and computational enhancement of QFT
Authors: Nataraj P. S. V.
Published: August 2002

The paper presents an overview of a mathematical and computational enhancement of Horowitz's QFT design procedure. The enhancement uses methods of interval analysis and is called as interval QFT, or IQFT. IQFT addresses and solves some of the fundamental issues in QFT, concerning selection of design frequencies, selection of controller phases in bound generation, approximation of plant templates with finite plant sets, and generation of plant templates and controller bounds with reliability and to a prescribed accuracy. An example is presented to illustrate the key features of IQFT. Copyright © 2002 John Wiley & Sons, Ltd.
Plant zero structure and further order reduction of a singular H∞ controller
Authors: Watanabe Takao , Stoorvogel Anton A.
Published: August 2002

A new class of reduced‐order controllers is obtained for the H∞ problem. The reduced‐order controller does not compromise the performance attained by the full‐order controller. Algorithms for deriving reduced‐order H∞ controllers are presented in both continuous and discrete time. The reduction in order is related to unstable transmission zeros of the subsystem from disturbance inputs to measurement outputs. In the case where the subsystem has no infinite zeros, the resulting order of the H∞ controller is lower than that of the existing reduced‐order H∞ controller designs which are based on reduced‐order observer design. Furthermore, the mechanism of the controller order reduction is analysed on the basis of the two‐Riccati equation approach. The structure of the reduced‐order H∞ controller is investigated. Copyright © 2002 John Wiley & Sons, Ltd.
Generation and forward displacement analysis of two new classes of analytic 6‐SPS parallel manipulators
Authors: Kong Xianwen , Gosselin Clément M.
Published: August 2002

Analytic manipulators are manipulators with a characteristic polynomial of fourth degree or lower. Using the component approach to generate analytic 6‐SPS parallel manipulators (PMs), the generation process is reduced to the generation of analytic components for 6‐SPS PMs. Two new classes of analytic components for 6‐SPS PMs are generated at first. Then, two new classes, IX and X, of analytic 6‐SPS PMs are generated. The forward displacement analysis (FDA) of the new analytic 6‐SPS PMs is also performed. The FDA of the 6‐SPS PMs of class IX is reduced to the solution of one univariate cubic equation and two univariate quadratic equations, in sequence, while that of the 6‐SPS PMs of class X is reduced to the solution of three univariate quadratic equations in sequence. Both of the new analytic 6‐SPS PMs have at most eight assembly modes. © 2001 John Wiley & Sons, Inc.
Fault detection and isolation in robotic manipulators via neural networks: A comparison among three architectures for residual analysis
Authors: Terra Marco Henrique , Tinós Renato
Published: August 2002

In this article we discuss artificial neural networks‐based fault detection and isolation (FDI) applications for robotic manipulators. The artificial neural networks (ANNs) are used for both residual generation and residual analysis. A multilayer perceptron (MLP) is employed to reproduce the dynamics of the robotic manipulator. Its outputs are compared with actual position and velocity measurements, generating the so‐called residual vector. The residuals, when properly analyzed, provides an indication of the status of the robot (normal or faulty operation). Three ANNs architectures are employed in the residual analysis. The first is a radial basis function network (RBFN) which uses the residuals of position and velocity to perform fault identification. The second is again an RBFN, except that it uses only the velocity residuals. The third is an MLP which also performs fault identification utilizing only the velocity residuals. The MLP is trained with the classical back‐propagation algorithm and the RBFN is trained with a Kohonen self‐organizing map (KSOM). We validate the concepts discussed in a thorough simulation study of a Puma 560 and with experimental results with a 3‐joint planar manipulator. © 2001 John Wiley & Sons, Inc.
Causal approximate inversion for control of structurally flexible manipulators using nonlinear inner–outer factorization
Authors: Cree A. G. , Damaren C. J.
Published: August 2002

A control scheme for flexible‐link manipulators is advanced which is based on the notion of nonlinear inner–outer factorization. It is well known that the inverse of the forward dynamics map from joint torques to manipulator tip motion is noncausal and cannot be implemented in conjunction with real‐time path planning. The methods used here determine causal approximations for the inverse dynamics using the inverse of the outer (stable and minimum phase) factor and a static approximation for the inverse of the inner (lossless but nonminimum phase) factor. The Hamilton–Jacobi equation that arises is approximated by a state‐dependent Riccati equation at each time step. The factorization procedure yields the corresponding joint trajectories which can serve as reference trajectories for closing joint‐based feedback loops. Experimental results from a planar three‐link manipulator with two flexible links demonstrate the efficacy of the procedure. © 2001 John Wiley & Sons, Inc.
A further result of the nonlinear mixedH2/H∞tracking control problem for robotic systems
Authors: Huang C. Q. , Wang X. G. , Wang Z. G.
Published: August 2002

The design objective of a mixedH2/H∞control is to find theH2optimal tracking control law under a prescribed disturbance attenuation level. With the help of the technique of completing the squares, a further result of the mixedH2/H∞optimal tracking control problem is presented, by combining it with standard LQ optimal control technique. In this paper, only a nonlinear time‐varying Riccati equation is required to solve the problem in the design procedure—instead of two coupled nonlinear time‐varying Riccati equations, or two coupled linear algebraic Riccati‐Iike equations—with some assumptions made regarding the weighting matrices in the existing results. A closed‐form controller for the mixedH2/H∞robotic tracking problem is simply constructed with a matrix inequality check. Moreover, it shows that the existing results are the special cases of these results. Finally, detailed comparison is performed by numerical simulation of a two‐link robotic manipulator. © 2002 John Wiley & Sons, Inc.
On the optimality of the random hyperplane rounding technique for MAX CUT
Authors: Feige Uriel , Schechtman Gideon
Published: August 2002

MAX CUT is the problem of partitioning the vertices of a graph into two sets, maximizing the number of edges joining these sets. This problem is NP‐hard. Goemans and Williamson proposed an algorithm that first uses a semidefinite programming relaxation of MAX CUT to embed the vertices of the graph on the surface of ann‐dimensional sphere, and then uses a random hyperplane to cut the sphere in two, giving a cut of the graph. They show that the expected number of edges in the random cut is at least α · sdp, where α ≃ 0.87856 and sdp is the value of the semidefinite program, which is an upper bound on opt, the number of edges in the maximum cut. This manuscript shows the following results: (1) The integrality ratio of the semidefinite program is α. The previously known bound on the integrality ratio was roughly 0.8845. (2) In the presence of the so‐called “triangle constraints,” the integrality ratio is no better than roughly 0.891. The previously known bound was above 0.95. (3) There are graphs and optimal embeddings for which thebesthyperplane approximates opt within a ratio no better than α, even in the presence of additional valid constraints. This strengthens a result of Karloff that applied only to the expected number of edges cut by a random hyperplane. © 2002 Wiley Periodicals, Inc. Random Struct. Alg., 20: 403–440, 2002
The ζ(2) limit in the random assignment problem
Authors: Aldous David J.
Published: August 2002

The random assignment (or bipartite matching) problem asks about An=minπ ∑c(i, π(i)), where (c(i, j)) is a n×n matrix with i.i.d. entries, say with exponential(1) distribution, and the minimum is over permutations π. Mézard and Parisi (1987) used the replica method from statistical physics to argue nonrigorously that EAn→ζ(2)=π2/6. Aldous (1992) identified the limit in terms of a matching problem on a limit infinite tree. Here we construct the optimal matching on the infinite tree. This yields a rigorous proof of the ζ(2) limit and of the conjectured limit distribution of edge‐costs and their rank‐orders in the optimal matching. It also yields the asymptotic essential uniqueness property: every almost‐optimal matching coincides with the optimal matching except on a small proportion of edges. ©2001 John Wiley & Sons, Inc. Random Struct. Alg., 18: 381–418, 2001
TCP modifications over satellite channels: study and performance evaluation
Authors: Marchese Mario
Published: August 2002

The paper presents a study and an analysis of the performance offered by TCP over a GEO (geostationary orbit) satellite link. The characteristics of satellite channels (notably the large round trip delay) heavily influence the TCP flow control, which is essentially based on acknowledgements. The effect is a delay in the acknowledgement reception and, consequently, in the delivery of messages, with respect to cabled networks. The drawbacks of using TCP in a satellite environment may be mitigated by a proper tuning of some TCP parameters. The behaviour of the protocol, as a consequence of variations in the buffer length of both transmitter and receiver and in the initial congestion window, is investigated in the paper and a proper configuration that drastically improves performance (measured by the throughput in bytes/s and by the overall transmission time) is proposed. Two test environments have been used to evaluate the proposed modifications: a real testbed, composed of two remote hosts connected through a satellite channel, and a satellite network emulator, composed of three PCs (two of them representing two hosts, the third one reproducing the behaviour of the satellite link). In both environments, a ftp‐like application designed for the aim has represented the reference application; three different file sizes have been used and the different effect of the tuning, depending on the transfer length, has been evidenced; the analysis includes both the single application case and the multiple application case, where several connections a time share the satellite link. Copyright © 2001 John Wiley & Sons, Ltd.
First year chemical engineering students' conceptions of energy in solution processes: Phenomenographic categories for common knowledge construction
Authors: Ebenezer Jazlin V. , Fraser Duncan M.
Published: August 2002

In this article, we examine first‐year chemical engineering students' conceptions of the energy changes taking place in dissolution. Students were individually interviewed with three tasks in which three different salts were dissolved in water, and 17 transcripts were analyzed using a phenomenographic methodology. Four descriptive categories of energy in dissolution were discerned: (a) you give energy (n= 1); (b) water gives energy (n= 17); (c) salt gives off energy (n= 13); and (d) reaction gives off energy (n= 7). Four students gave the same explanation for all three tasks, but more students used the same explanation for two of the tasks: four for Tasks A and B, four for Tasks B and C, and eight for Tasks A and C. Moreover, “salt gives off energy” was the most common explanation for Tasks A and B (n= 3), “reaction gives off energy” for Tasks B and C (n= 3), and “water gives energy” for Tasks A and C (n= 8). Four of the students showed variations of conception within tasks. Students described the solution process of all three tasks using a range of concepts, including previously learned chemical concepts. Even where students used the same chemical concepts in each of the tasks, they did not always give the same meaning to the concepts they used. The phenomenographic categories explanations given by students were used as a basis for developing an approach to teaching energy in solution processes. It is argued that this approach of using phenomenographic categories described at a collective level as a basis for discourse for constructing common knowledge should be used in teaching. It is proposed that a future study must be conducted to develop new trajectories students take to arrive at common knowledge and to understand how to move learners from their personal conceptions to plausible models in solution chemistry within the classroom learning community. Implications for policy are also discussed. © 2001 John Wiley & Sons, Inc.Sci Ed85:509–535, 2001.
The future of Lisp
Authors: Takeuchi Ikuo
Published: August 2002

Lisp has taken root widely and deeply in various fields, despite the decline of the AI fever in the 1980s and the common belief that Lisp has long been only a laboratory programming language. In the age of heterogeneous parallel computing, certain languages will survive and consolidate their positions. Lisp is surely classified among these languages. Moreover, Lisp has the potential to be a good system programming language, even suitable for writing an operating system, if real‐time garbage collection technology is further matured. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(6): 10–18, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10000
Vision system for object handling robot using a low‐resolution range image and an intensity image
Authors: Hashimoto Manabu , Haga Tetsuji , Sumi Kazuhiko
Published: August 2002

In this paper, we propose an object recognition system which consists of two modules. One is an object extraction module using a low‐resolution range image. The other is a position measurement module for detecting precise position of each object using an intensity edge image. To acquire a range image, we propose stereo vision with random‐dot pattern projection. This method enables reliable stereo matching, even if there is no texture on the objects. The equipment is simple because a variable pattern is not necessary. We found this system has 99.8% recognition reliability and the processing time is approximately 5 s/image, providing satisfactory performance for practical use. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(7): 21–29, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10055
An enhanced fault model for high defect coverage
Authors: Sang Junzhi , Shinogi Tsuyoshi , Takase Haruhiko , Kita Hidehiko , Hayashi Terumine
Published: August 2002

In this paper, we propose an enhanced fault model to increase coverage in detecting physical faults in LSI. First, as an alternative to the single stuck‐at fault model, we propose the “single gate logical fault with Hamming distance 1” (SGLFH1) model, which is capable of generating test pattern sets that detect more defects from the same number of faults. The characteristics of this fault model are discussed and the effectiveness of the test pattern sets generated by it is described. Next we show that the multiple detection test pattern set for single stuck‐at faults that is conventionally used to enhance defect coverage does not detect SGLFH1 faults satisfactorily. In addition, the effectiveness of the proposed model is shown by comparing the fault detection ratio of the SGLFH1 test pattern set for physical surrogate faults [1, 2] with the corresponding fault detection ratio of the multiple detection test pattern set for single stuck‐at faults. © 2001 Scripta Technica, Syst Comp Jpn, 32(6): 36–44, 2001
Analyzing social interactions in a mobile computing environment and application to agent communication service: Experiments under the ICMAS'96 mobile assistant project
Authors: Nishibe Yoshiyasu , Waki Hiroaki , Morihara Ichiro , Hattori Fumio
Published: August 2002

Expectations for communication services in a mobile environment grow with the spread of portable computers and cellular telephones. However, knowledge of users' behavior in a mobile environment is necessary to judge the constraints imposed on users, and functions that agents must offer to users. The authors provided a variety of mobile services (not only conventional e‐mail but also information guides related to conference schedule, area, and so on) to more than 100 participants of an international conference through portable terminals and mobile telephones; in so doing, massive usage data were acquired. These usage data were compared to those of commercial services using the same terminals, and mobile computing usage proved to be clearly reflective of users' everyday activity patterns. The following facts that were revealed should be taken into account when designing information services under mobile environment. (1) A remarkable trade‐off exists between frequency of access to server, and size of data downloaded to terminals. (2) Impatient users are likely to cancel data acquisition, or to terminate communications. Proceeding from the obtained results, the following functions were shown to be necessary for agents in mobile environment: (1) distribution of information between server and terminals; (2) technological and psychological measures to encourage users to employ server connections. © 2001 Scripta Technica, Syst Comp Jpn, 32(7): 62–70, 2001
Language modeling by stochastic dependency grammar for Japanese speech recognition
Authors: Ito Akinori , Hori Chiori , Katoh Masaharu , Kohda Masaki
Published: August 2002

This article has been removed by the publisher.