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GANIL-EXP; Results on projectile fragment–fragment coincidences in the forward direction and for the reaction 40Ar + 27Al at 44 A MeV are presented and compared with the predictions of two different entrance channel models, a two-body and a three-body mechanism both followed by a binary multisequential decay including fission. This analysis shows that many features of the projectile decay products are well accounted for by the binary multisequential decay model. However the results depend critically upon the initial masses and excitation energies of the primary projectile fragments. In this respect, the three-body approach underestimates the excitation energy imparted to the primary fragments whereas the two-body scenario overestimates it. The present data put strong constraints on the initial excitation energy imparted to the primary fragments which appears to be intermediate between the predictions of the two models.

This paper describes the application of real-time simulation tools and how automation techniques can be used during the development process of modern automotive electronic control units (ECUs) in order to effectively meet the demands placed by the increasing complexity of the software and the resulting intricate ECU tests. Hardware-in-the-loop simulation along with test automation is increasingly important for the efficient integration of production type engine ECUs. With more and more manufacturers relying on independent suppliers, the need for automatically testing black box systems, including closed-loop and open-loop functions, self-diagnoses, failure memory management and the triggering of failure lamps, becomes paramount.

The problems of designing mechatronic systems (e.g. heterogeneous system components and their design methods, complexity) cause the need for an open, integrated design environment. This paper details the process-oriented approach of the software environment CAMeL (Computer-Aided Mechatronics Laboratory) to the integration of different tools and methods. Characteristic concepts and implementation features of experiments in this "laboratory in the computer" are presented. An example from the field of vehicle dynamics (vehicle convoy control) demonstrates typical experiments in the modelling, analysis and synthesis phases of the design cycle of mechatronic systems.

This paper introduces the design environment CAMeL (Computer-Aided Mechatronic Laboratory) which supports the whole design cycle of mechatronic systems. Modern CACSD tools have to be open and easily combinable with other existing tools designated to perform special design tasks. CAMeL is a process-based development framework for control systems. Beside an internal toolset for linear analysis, nonlinear simulation and optimization based on the system description language DSL, CAMeL has the possibility to use other, i.e. commercial design environments to enhance its performance. In addition, CAMeL software processes are able to communicate online with technical processes. Thus design and optimization of controllers can be performed directly in the real plant. >

To assess the ability of baseline MRI characteristics to predict the early development of clinically definite MS (CDMS) and combined CDMS/MRI outcomes in 190 patients with a positive MRI at the time of their first demyelinating event.Based on individual and sets of baseline MRI characteristics, the authors evaluated the percentage of patients meeting outcomes of CDMS and various combined CDMS/MRI outcomes by 18 months. They also optimized a cutpoint for dichotomizing each baseline MRI characteristic and evaluated these variables using logistic regression to determine which MRI characteristics best predicted CDMS by 18 months.The presence of two or more gadolinium-enhancing lesions better predicted the development of CDMS and combined CDMS/MRI outcomes by 18 months than any other individual MRI characteristic or set of MRI characteristics. Among patients with two or more gadolinium-enhancing lesions, 52% developed CDMS compared with 24% of patients with fewer than two lesions. For those meeting the criteria of Barkhof et al., 32% of patients developed CDMS compared with 16% of those not meeting these criteria. Irrespective of individual or sets of criteria, however, the majority of patients developed either CDMS or demonstrated disease activity on brain MRI by 18 months.For patients with positive MRI at the time of their initial neurologic event, both gadolinium-enhancing lesions and the Barkhof criteria are predictors for development of CDMS over a short interval. However, these results, based on a combined CDMS/MRI outcome, suggest that the majority of these patients are already in the earliest stages of MS, regardless of whether any further MRI criteria are met.

The properties of excited nuclear matter and the quest for a phase transition which is expected to exist in this system are the subject of intensive investigations. High energy nuclear collisions between finite nuclei which lead to matter fragmentation are used to investigate these properties. The present report covers effective work done on the subject over the two last decades. The analysis of experimental data is confronted with two major problems, the setting up of thermodynamic equilibrium in a time-dependent fragmentation process and the finite size of nuclei. The present status concerning the first point is presented. Simple classical models of disordered systems are derived starting with the generic bond percolation approach. These lattice and cellular equilibrium models, like percolation approaches, describe successfully experimental fragment multiplicity distributions. They also show the properties of systems which undergo a thermodynamic phase transition. Physical observables which are devised to show the existence and to fix the order of critical behaviour are presented. Applications to the models are shown. Thermodynamic properties of finite systems undergoing critical behaviour are advantageously described in the framework of the microcanonical ensemble. Applications to the designed models and to experimental data are presented and analysed. Perspectives of further developments of the field are suggested., Comment: 150 pages including 28 figures. To be published in Phys. Rep. Corrected discussion in section 3.2.3 and new Fig.5. New caption of Fig.28

We use a binary sequential decay model in order to describe the fragmentation of a nucleus induced by the high energy collisions of protons with Au nuclei. Overall agreement between measured and calculated physical observables is obtained. We evaluate and analyse the decay times obtained with two different parametrisations of the decay rates and discuss the applicability of the model to high energy fragmentation., Comment: 6 pages, 4 eps figures. Small changes at the end of the text. More arguments are given in the discussion of the time scale of the process

We introduce a method based on the finite size scaling assumption which allows to determine numerically the critical point and critical exponents related to observables in an infinite system starting from the knowledge of the observables in finite systems. We apply the method to bond percolation in 2 dimensions and compare the results obtained when the bond probability p or the fragment multiplicity m are chosen as the relevant parameter., 12 pages, TeX, 4 figures

We investigate the thermodynamical content of a cellular model which describes nuclear fragmentation as a process taking place in an excited disordered system. The model which reproduces very well the size distribution of fragments does not show the existence of a first order phase transition., 14 pages, TeX type, 7 figures

Fission barriers, level densities, mass and friction parameters of hot rotating nuclei along the fission path are calculated in a multidimensional deformation space. The shape parameterization of Trentalange, Koonin and Sierk is used in order to test higher multipole effects on the collective potential, moment of inertia, collective mass and friction coefficient which enter a dynamical description of the fission process in terms of a unique collective variable. The dependence of the level density parametera on mass number, neutron excess and deformation is analyzed. All calculations are performed for medium-mass to heavy nuclei.

The dependence of the transmission coefficient on the deformation, the collective rotation and excitation energy of the compound nucleus emitting light particles is introduced in the framework of Wei{\ss}kopf's evaporation theory. The competition between fission and particle evaporation is treated by a~Langevin equation for the fission variable coupled to the emission process. Detailed calculations are presented on the decay of different Gd and Yb isotopes at an excitation energy of about 250~MeV. These calculations demonstrate the importance of the effects of nuclear deformation and of the initial spin distribution on the evaporation., Comment: 22 pages in LaTeX and 26 PS-figures included

In comparison with the $WT$ chiral identity which is indispensable for renormalization theory, relations deduced from the non-linear chiral transformation have a totally different physical significance. We wish to show that non-linear chiral transformations are powerful tools to deduce useful integral equations for propagators. In contrast to the case of linear chiral transformations, identities derived from non-linear ones contain more involved radiative effects and are rich in physical content. To demonstrate this fact we apply the simplest non-linear chiral transformation to the Nambu-Jona-Lasinio model, and show how our identity is related to the Dyson-Schwinger equation and Bethe-Salpeter amplitudes of the Higgs and $\pi$. Unlike equations obtained from the effective potential, our resultant equation is exact and can be used for events beyond the LEP energy., Comment: 17 pages in tex, to appear in Z. Phys. C

We calculate the electromagnetic radiation generated by the damped quadrupole surface vibrations of two fragments originating from the spontaneous fission of a heavy nucleus. We investigate the dependence of the spectral energy distribution of the radiation on the parameters of the model and on the initial conditions. The sensitivity of the results to the model parameters shows that theγ emission may be a good test of transport theories used in the description of this type of phenomena.

First we wish to express our thanks to the organizers of this conference, and to Professor Gruber in particular, to have given us the opportunity to dedicate this talk to Professor Biedenharn. Many of us in today’s gathering are Professor Biedenharn’s friends of many years who have so much appreciated his acquaintanceship. We all know how attentive he is to people around him. He often, this morning also, has praised some of his colleagues for being fine fellows. In fact their fineness is more the reflection of the profound generosity and warmheartedness of Professor Biedenharn towards them. I myself have learned a lot from him.

Nuclear fragmentation at high energy shows characteristic features which may serve as a guideline for the description and understanding of the mechanisms leading to experimentally observed mass or charge distributions. Results obtained by means of different models proposed in the past are analysed and discussed. Using the available information, recent efforts made in order to find the clue of the mechanisms which lead to the disassembly of nuclei are presented.

We analyse and discuss the information contained in mass and charge distributions obtained through a sequential model which is aimed to describe the decay properties of excited nuclei. We test the sensitivity of the distributions to the choice of different decay rates corresponding to different mechanisms. We look for signals which could characterise the thresholds of different decay regimes, i.e. phase transitions and(or) intermittency.

The decay of excited nuclei is described as a chain of sequential binary processes which lead to final mass and charge rates. We introduce moments of these rates and related observables. The results are discussed in the light of the percolation theory predictions.

Sequential decay of excited nuclei is described as a succession of binary processes which lead to final mass and charge distributions. The production rates are obtained event-by-event by means of Monte Carlo simulation techniques. Moments of the distributions and other observables calculated for three different excited nuclei are compared with those obtained from percolation models. The results are discussed in the framework of the universality predictions of percolation theory.

Purpose: To improve dose homogeneity in segmented‐field electron conformal therapy by matching penumbra of abutted fields. Method and Materials: A Varian 21EX electron applicator was modified to allow for energy‐dependent positioning of Cerrobend inserts resulting in energy‐dependent air gaps. Air gaps were chosen based on theoretical calculations to approximately match penumbra for 6, 9, 12, 16, and 20 MeV beams at 1.5‐cm depth in a water phantom at 100‐cm SSD. Treatment plans developed for four simulated target volumes using the modified applicator were compared to identical plans using the standard applicator. Improvement in dose homogeneity was assessed by comparing maximum and minimum dose, mean dose, and sigma of the dose distribution in the target volume for the two plans. Subsequently, electron blocks were cut with diverging edges using the Compu•cutter® system, and dose plans using the modified applicator were delivered to Kodak XV film in a polystyrene phantom to demonstrate feasibility. Results:Treatment planning results using the modified applicator showed improved dose homogeneity in all four simulated target volumes as compared to plans using the standard applicator. Averaged for all four PTVs; dose spread (Dmax − Dmin) decreased by 35%, σ of the dose distribution decreased by 29%, and D90–10 decreased by 31%. Dose delivered to a film phantom using the modified applicator was found to agree well with predictions (within approximately 5%) of the Pinnacle treatment planning system in the abutment region of the PTV (±2 cm from the abutment edge at depths ⩾1.5 cm). Conclusion: The results of this study suggest segmented‐field electron conformal therapy can be delivered with significant improvement in dose homogeneity as compared to the current method by using energy‐dependent positioning of electron inserts to match beam penumbra.

The relationship between exercise patterns and possible risk for eating disorders was examined in a survey of undergraduates using the Eating Attitudes Test (EAT). Reported hours of jogging per week correlated positively and significantly with total EAT scores and with scores on the “Dieting” factor. The Dieting factor also showed significant correlations with number of activities and total hours of activities. Subjects with EAT scores at or above 30 showed a significantly higher mean number of hours of jogging per week than subjects with EAT scores less than 30. Total EAT scores and each of the three factor scores showed a significant positive correlation with exercising alone. Overall levels of activity and hours spent in activities other than jogging did not relate to total EAT scores nor differentiate between the high and low EAT score groups. The apparent preference for jogging among those possibly at risk for eating disorders is discussed in terms of sociocultural and dynamic factors associated with eating disorders.

The cross-situational stability of defensive style was investigated by administering the Defense Mechanisms Inventory to 52 undergraduate students. Analyses of variance were performed on each of the two defensive style variables and percentages of variance accounted for by persons, situations, items and their interactions were estimated from the mean squares. Persons and the person-situation interaction accounted for approximately equal percentages of variance in both defensive styles. Implications of the results for conceptualizing defensiveness and for the utility of defensiveness as a moderator variable are discussed.

Numerical methods and statistical tests are described which form part of a recent paper dealing with Hauser-Feshbach theory in the presence of direct reactions.

We present formulas for the auto- and cross-correlation functions of various observables, taking into account the influence of direct reactions. These formulas are valid in the limit of strong absorption, and are deduced from the statistics of the nuclear matrix elements. We thereby put fluctuation theory on a new basis, and extend its domain of validity by including direct reactions. We obtain an explicit expression for the correlation length. Numerical calculations show that our formulas apply only in the strong-absorption limit, and that significant deviations occur for medium or weak absorption. We apply our results to the calculation of the cross-correlation function for the cross sections for elastic and inelastic proton scattering on88Sr through the 3/2+ isobaric analogue resonance.

The partition function in quantum statistical mechanics can be expressed as an energy integral of exp(- beta E) times the discontinuity of the Green function. A Monte Carlo approach for its evaluation which is not based on path integral representation is suggested. The fermion problem is avoided in the sense that all integrands are positive. Some weak points are underlined. The authors also discuss the evaluation of statistical averages using the pertinent procedure.

Sex-role appropriateness of a behavior and four cognitive variables were studied as predictors of variability in behavior. Behavioral observations were made on 12 male and 13 female undergraduate subjects interacting with a female accomplice in two experimental situations. Analyses of the data showed that sex-role appropriateness did not relate consistently to behavioral variability. Some support was found, however, for a relationship between cognitive abilities and variability across situations in certain behaviors. The implications of the data for operationalizing cognitive abilities and for using artificially constructed situations in interaction research are discussed.

The effects of situation, sex, and four cognitive abilities on the variability of behavior both within and across two social situations were examined. 12 male and 13 female undergraduate subjects interacted with a female accomplice in two interpersonal situations. Behavioral variability was derived from codings of videotapes of the subjects' behaviors. The person-situation interaction was central, and there were also important effects for sex; women tended to be less variable. Significant negative correlations were found for variability in behavior, both within and across the two situations, with divergent production of behavioral systems. Cognition of behavioral relations also showed significant correlation with variability within the more unusual of the two interpersonal situations. The other two cognitive ability variables did not show any significant relationships to behavioral variability. The results are discussed in terms of the integrative functions of systems and the relative differentiation of the experimental situations as opposed to naturally occurring situations.

The TDHF equations are formulated for the Wigner transform of the single-particle density matrix. These equations are solved numerically by expanding the Wigner transform in terms of harmonic functions. In some of the calculations a collision term is included which is based on a simple-minded ansatz. Results of the calculations are presented and compared with each other.

We define and derive the probability of presence at a given point in space and time of a one-dimensional quantum system which interacts with an external system. The probability is expressed in terms of a double path integral which contains memory effects. We show that it is possible to get a simple compact algebraic expression of the probability as the continuum limit of a discretized form of the path integrals.

Some properties of Pade approximants to effective interactions in nuclei are investigated. The behaviour of higher order approximants is discussed in model calculations. In the case of [2, l]-approximants a criterion is derived for the occurrence of spurious poles which are not related to level crossings.

Student volunteers from introductory psychology classes who received credit for participation were sampled near the beginning, middle, and end of the quarter. Half the subjects were given a hidden-figures task; half a visual-search task. All 174 subjects then rated several concepts using a semantic differential and completed a social desirability and an authoritarianism scale. A significant performance decrement was found for later samples on the visual-search task but not on the hidden-figures task. There was a significant decline in favorableness of self-evaluation over quarters for subjects given the visual-search task but not for those given the hidden-figures task. Females evaluated themselves more favorably when given the hidden-figures task; males did not. The hidden-figures task was rated more favorably, and females rated research more favorably. Results are discussed in terms of varying motivations in early vs late volunteers and in terms of the level of interest evoked by the tasks.

Several methods are investigated to deal with the singularities of the effective interaction which cause the perturbation series to diverge. Some of these methods, which are found to be quite useful, are based upon a semiphenomenological treatment of the “intruder” states. One method, based upon the use of Pade approximants, seems to be free of such semiphenomenological input data and appears to yield a particular effective interaction which has as eigenvalues those levels of the system for which the corresponding eigenfunctions have maximum overlap with the model space. The methods are investigated with the help of simple examples. Those methods which are found to be useful are applied to the 0 + and 2 + levels of 18 O.

We investigate the nature of the disassembly process leading to the mass and isotopic distributions of fragments which were recently measured in the reaction40Ar on13C at an energy of 27.5 MeV per nucleon. The experimental distributions of intermediate and heavy mass species are compatible with a sequential decay mechanism. Calculated isotopic distributions are also in satisfactory agreement with the experiment. A moment analysis of the mass distributions in the spirit of percolation theory is performed. We do not see the expected critical behaviour of the system as a function of the temperature. We present some arguments about the reasons for this behaviour.

The present data suggest sex differences (27 men, 19 women; 18.5 and 17.8 yr. old on average) in the relationship between externality of locus of control and reported anxiety. A positive linear relationship was found between these variables in different situations for men and women and between externality and different expressions of anxiety for each sex. The data support an interaction of values and expectancy in anxiety.

This paper deals with the determination of an effective interaction for shell model calculations in the (f, p) shell. The interaction consists of two parts. The first one is determined from a realistic nucleon-nucleon potential, the second is a tensor-force ansatz acting at the surface of the nucleus. Justifications for the use of this ansatz are given. The parameters appearing in the interaction are fixed by considerations on single-particle energy splittings. The matrix elements are used in a spectroscopic study of44Ti and60Zn. A certain number ofE2 transitions rates are evaluated. The agreement with former studies is shown to be good. Wave functions are analysed and comments about the link between model space and effective interaction are made.

Nous avons calcule la suite des niveaux ainsi que certaines probabilites de transitions reduites dans les noyaux 58Ni et 56Co. Nous avons utilise les techniques du modele en couches (incluant dans la base choisie les excitations 1t-1p du cœur) et une interaction effective de surface. L'accord avec les resultats experimentaux en ce qui concerne les niveaux est bon, certaines transitions electromagnetiques cependant restent encore inexpliquees.

The 1]~-2pg shell has long been one of the most studied nuclear regions. Recently there has been an extensive effective-interaction calculation on calcium isotopes by F~I)~MAN~ and PITTnL (1). The single set of matrix elements given by them has a good convergence and appears to reproduce the energy spectra, (t,p) strengths and single-neutron spectroscopic factors with reasonable agreement. Moreover, the /~pg matrix elements have the desh'ed feature of repulsion on the average. This is in agreement with the findings obtained by analysing the data from (3He, d) and (d, p) measurements in this shell (~). These matrix elements, derived from Hamada-Johnston potential (a), are, however, attractive on the average. The effective-interaction method in the framework of the shell model has the disadvantage that one cannot use a large configuration space in such calculations. Then the number of variable two-particle matrix elements increases drastically and the method fails. Even in a reasonable configuration space, the two-particle matrix elements obtained from the least-squares fit to the experimental binding energies and level energies of calcium isotopes have large statistical errors (a-e), when all the required two-particle matrix elements are allowed to vary. On the other hand, a large configuration space can be used with a phenomenological effective two-body interaction with a few adjustable parameters. The wave functions thus obtained, in view of greater configurational freedom, are more realistic than those obtained by the effective-interaction method. But it is difficult to get detailed quanti tat ive fit to the binding energies and level energies like the effective-interaction method because there are only a few adjustable parameters in a phenomenological force. So an initial test of a phenomenological residual twobody interaction is to reproduce the matrix elements obtained by the effective-interaction method to get a good description of the experimental data.

Shell-model calculations of 56Ni, 58Ni, 54Fe and 36Fe are presented. States are assumed to belong to configurations involving no excitation and two-particle excitations from the 1 f 7 2 shell. A limited number of core-excited states corresponding to four-particle excitations are also taken into account in the cases of 56Ni and 58Ni. The effective two-body interaction in the (1f, 2p) shell is deduced from a non-local potential which reproduces the nucleon-nucleon scattering data. Calculated energy spectra and transition rates are not in good agreement with experiment. This is certainly related to the truncation of the basis. Some improvements are obtained when single-particle energy spacings are allowed to vary.

Rifampin partially inhibits focus formation and virus production in chick embryo fibroblasts infected with Bryan high-titer Rous sarcoma (RAV-1) virus. This inhibition occurs with exposure to rifampin during a critical period between day 1 and day 2 after infection. This suggests that the drug does not affect formation of the provirus or its transcription or translation after the “fixation” step, but it seems to affect one or more events which take place before fixation and activation of virus production.

We diagonalize the Hamiltonian of a (4p-4n) system in the f 7 2 shell using the roton model of quartets. The spectra and wave functions of 0 + states are compared with those given by the shell-model.

We use Pade approximants to calculate the effective interaction W. Numerical studies indicate that this W approximately reproduces those eigenvalues of the full Hamiltonian for which the associated wave functions have maximum overlap with the model space. This W is the effective interaction of the shell model. The method of calculation is applicable when the usual perturbation expansion for W diverges.

The lifetimes of the first two excited states in Ni56 have been investigated using the reaction Fe54(He3,nγ)Ni56 and the Doppler-shift attenuation method. Pulse-shape discrimination was employed for the neutron-γ-ray coincidence measurements. These measurements lead to the following mean lives: τ(2699 keV)=76−24+49 fsec and τ(3924 keV)>1 psec. The E2 transition strength for the 2+→0+ transition is compared to shell-model predictions.

In this paper, we analyse the sensitivity of the theoretically calculated spectra of 56 Ni and 54 Fe against single particle energy variations and compare our results with those presented in previous works by other authors.