bluuebunny/crossref_metadata_2025 huggingface dataset:
The Social Unconscious Reflected in Politics, Organizations and Groups: A Case of Overseas Group Analysis Training
Authors: Hadar Bracha , Ofer Gila
Published: July 2003

The aim of this article is to study the impact of parallel processes operating in the overlapping dimensions of history, politics, society, organization, staff and group participants. The focus of the article is the effort to try and make personal sense of and reach a professional understanding of an annihilating, painful process that took place due to combined forces, which will also be examined. These forces, which are of an unconscious, preconscious and conscious character, are very powerful and still exist. Bion's concepts of alpha and beta elements, as applied to organizations, and Nitsun's concept of the anti-group will be discussed as theoretical background that can explain some of the destructive forces. Some moderating factors essential to processes of survival and re-creation and other conclusions will also be discussed.
The Ones Left Behind: A Siblings' Bereavement Group
Authors: Moss Eric , Raz Avivia
Published: July 2003

An analytic therapy group for family members of murdered victims of terrorist attacks offers particular benefits. This article discusses one such group, the members of whom were 12 surviving siblings of victims of terrorist attacks in Tel Aviv. Usually bereft of people with whom to share their darkest feelings, these siblings found among the group members people with whom they could do so. Their individual mourning processes were facilitated, and they were helped to move back into life. The firm analytic group boundaries and constancy were critical therapeutic elements, as were the conductors' attention to transferential and countertransferential processes. One peculiarity of the group was an uncanny sense of the ongoing presence of the murdered siblings.
Culture, Politics and Group Therapy: Identification and Voyeurism
Authors: Stone Esther G.
Published: July 2003

For many months during the summer and fall of 1998, the USA was deluged by information about the sexual exploits of President Clinton, Monica Lewinsky, and their legal battles with Ken Starr Voyeurism was stimulated not only in the USA but around the world. Inevitably, the combination of use and abuse of power combined with sexuality crossed into the treatment room. A clinical example will illustrate the impact of these events on the members of a long-term group. The members assume emotional positions similar to the main political participants, and in the process reexamine their fears of exposure, sexual guilt and fundamental self-doubts. The discussion will offer ideas about the meaning of this replay of previously worked themes in light of transference and countertransference considerations.
The Change Process of a Patient in Long-Term Group Psychotherapy: Measuring and Describing the Change Process
Authors: Lorentzen Steinar , Høglend Per
Published: July 2003

Given the complexity of analytic therapies and individual change, it seems desirable to introduce more objective and quantitative measures into the clinical situation in assessment of change. A traditional case study describes one patient's change pattern in symptomatic distress, interpersonal relations and self-esteem during 44 months of group analysis. We hypothesized that change described by repeated applications of self-report measures (SCL-90-R, HP, and SASB) would converge with the clinical narrative. This was confirmed for symptoms and interpersonal problems. However; in early and middle phase of therapy during periods of deterioration, negative aspects of her self-image at worst (self-attack, self-neglect) improved. During the same periods she suffered from a pronounced feeling of depersonalization. For the remaining part of the therapy; including a period after a miscarriage later in therapy, she was able to experience the negative aspects of her self-image at worst. The feeling of depersonalization was then much less pronounced. Her complex SASB-patterns may represent a split of internal self-representations, seen in certain personality disorders. More studies are needed.
Talking Gender in the Group
Authors: Rose Chris
Published: July 2003

Research into the relationship between language and gender challenges group psychotherapy to pay attention to the significance of gender in shaping the language used by members and conductors. Language is a major resource in the creation of our gendered sense of self, with styles stereotypically associated with male and female. The linguistic culture of the group has stereotypical `male' and `female' aspects. The language of the therapist is critical in establishing linguistic norms, challenging or reinforcing gender stereotypes. The movement from these stereotypical styles, with the ability to draw upon both `male' and `female' characteristics, is a therapeutic movement. The absence of critical analysis of these aspects of language and gender in group theory witnesses to the power of the `social unconscious'.
Work with Psychotic Patients in a Rehabilitation Unit: A Short Term Staff Support Group with a Nursing Team
Authors: Novaković Aleksandra
Published: July 2003

The author documents difficulties that arose in the work of a team working in a residential setting providing 24 hour care for patients with repeated or long-term admissions, and the different, inter-related and mutually dependent aspects of this work. Issues that emerged included the difficult nature of work with this patient group, collaborative work in the team, management issues and models of care, i.e. active rehabilitation ideology. Staff encountered problems which were not unique to this team, and which have wider implications for other staff working in similar roles and contexts with a similar patient group.
Organizational Psychology Programme at the Institute of Group Analysis (Copenhagen): A Training Programme in Group Analysis and Group Relations
Authors: Heinskou Torben
Published: July 2003

This article describes a training programme in organizational psychology for executives, managers and consultants at the Institute of Group Analysis in Copenhagen. Over a two-year period, the programme combines continuous activities with separate working conferences. The emphasis is on combining experience of group analysis with the tradition of working conferences as carried out at the Leicester conferences organized by the Tavistock Institute of Human Relations - and systemic thinking. The article includes a detailed account of the organization and background of the programme, with the results of evaluations by the first five classes of participants (from 1994 to 1999) presented. The general opinion of the 96 graduates who have completed the programme is that they profit most from working with analysing person-related themes in organizational psychology.
All of us: A Search for the Meaning of the Matrix
Authors: MacDonald Pat
Published: July 2003

S.H. Foulkes, who argued that we are all essentially group beings, established a school of analytic belief and practice where the group is central. The group therapy space is a field of imagination and a forum for the creation of meaning through a shared network which Foulkes calls the matrix. Although the matrix lies at the very heart of Foulkesian discourse, it is difficult to make sense of the concept and get a clear understanding of this source of all group energy and activity. Theories lack meaning unless integrated into individual practice and this article reflects an attempt to identify and record the process whereby a matrix or shared network evolved in the early stages of a training group.
Group Analysis and Eating Disorders
Authors: Willis Sally
Published: July 2003

In focusing on eating disorders patients as a special application for group-analytic therapy, this paper first examines four central concepts of Foulkes in order to establish the effectiveness of group analysis. The role of the conductor is observed and discussed with particular reference to establishing a good-enough containing environment for group members. Phases of development within the group are documented as well as relationships between group members and how these affect the group's approach to a new conductor and the prospect of future challenges.
Consuming Passions: Groups for Women with Eating Problems
Authors: Hudson Inge , Ritchie Sheila , Brennan Clare , Sutton-Smith Deirdre
Published: July 2003

This is an account of time-limited focal group-analytic therapy for women with bulimia and compulsive eating problems in an all-women context at the Women's Therapy Centre, London. Eating problems are understood within the context of the early mother-daughter relationship and there is an account of how these dynamics are played out within the groups. The authors describe their understanding of transference and countertransference phenomena and the use of metaphors to achieve a process of translation from the concrete language of food, eating and the body to the language of feelings and relationships. They demonstrate how homogeneous groups for these women provide the opportunity for them to see their difficulties reflected in others, thereby enabling them to make the link between their relationship with food and the body and their internalized objects. Throughout the article there is an attempt to locate the work within a social context.
From Silent Scream to Shared Sadness
Authors: Wood David
Published: July 2003

This article describes the development of group-analytic psychotherapy with anorexic children and adolescents in an inpatient setting. A particular point of emphasis is on the way the therapy groups evolved `spontaneously' from the group matrix within the clinic and the importance of responsiveness and `affect attunement' in the process.
Anorexia as a Symbol of an Empty Matrix Dominated by the Dragon Mother
Authors: Weston Marisa Dillon
Published: July 2003

This article reports the author's understanding of anorexia reached through her clinical work and using Jungian as well as group-analytic concepts. Examples of individual, family and group work are given and they constitute facets of an overall picture of devouring hunger against the background of a depleted matrix.
Between Idealization and Devaluation
Authors: Wuhrmann Sonja
Published: July 2003

This article examines the working and personal relationship between two co-conductors of a group of adolescent women with eating disorders, and how this relationship changes and contributes to the significance of the countertransference process.
Trigant Burrow's Group Analysis
Authors: Gilden Lloyd
Published: July 2003

Two related aspects of the group research of Trigant Burrow are discussed: the development and structure of the self-image, called the `I'-persona by Burrow, and the protocol of Burrow's group analysis. The `I'-persona is viewed as the product of social conditioning and considered to be at the root of interrelational conflict, due to its propensity to pursue its own interests at the expense of the common interests of the group. The objectives of Burrow's group analysis are to identify the manifestations of the `I'-persona's self-serving, oppositional tendencies as they arise in the group context, and to transform those tendencies to more cohesive interrelational behavior by employing a somatic technique that involves the shift of attention from the self-image to organismic and proprioceptive sensations.
Trigant Burrow and Unearthing the Origin of Group Analysis
Authors: Pertegato Edi Gatti
Published: July 2003

This article details the events that prompted the author to go on the track of Trigant Burrow. It recounts how group analysis originated from psychoanalysis, gradually leading to the formulation of its theoretical-methodological structure. It also deals with the many difficulties Burrow had to face due to his ostracism by Freud and the psychoanalytic community.
History, Concept and Position of Self-Help Groups in Germany
Authors: Moeller Michael Lukas
Published: July 2003

Those responsible for medical care only reluctantly concede the true existence of the duality between highly technical medical support and compassionate medical support. The latter does not receive its fair share of attention. In view of the tremendous expansion of technological quick-fix medicine - driven in part by the demands of patients themselves - the situation will not change. This huge deficit of modem medicine led to the growth of self-help groups. The maxim of self-help groups in the United States - `Doctors know better than we do how a sickness can be treated. We know better than doctors how sick people can be treated as humans' - expresses in a nutshell, the complementary relationship between self-help groups and medical care. The author's twenty-five years of practical experience in furthering the self-help movement and its work are the background for outlining the development of group self-help, and the current threat of resistance to the dynamic potential of self-help groups. Furthermore, it makes it possible to describe a time-tested model for cooperation between self-help groups and their professional support workers that augments the autonomous group meetings primarily with a so-called general meeting. This mobilizes self-development without leading to new dependencies. The future of medicine and presumably also of psychotherapy is no longer imaginable without dynamic self-help groups.
Group Analysis in the Ukraine
Authors: Mahler-Bungers Annegret
Published: July 2003

This article presents a training project in the Ukraine which has been realized since 1994. It discusses the difficulties and unconscious meanings of working in a foreign culture and of being dependent on an interpreter The expectations and attitudes of the participants are shown to contain anachronisms. These are examined in the light of Ukrainian history and present political situation on the one hand, and of the group process on the other. The most important effect of this work seems to be the change from understanding group analysis as a new dictatorial system, to internalizing its setting as a potential space which provides a frame for free dialogue and intimacy. In this way group analysis can help to develop a deeper understanding of democratic processes.
Power, Institution and Group-Analytic Training
Authors: Marten Robert F.
Published: July 2003

This article is concerned with the origins, conscious and unconscious, of the distribution of power on the Zurich training course in Foulkesian group analysis. It considers critically the historic origins of the institutionalization of psychoanalysis, its resulting present power structure and the consequence for the psychoanalytic training institutes. Turning to its offspring - group-analytic training institutes - their conscious `ideology' and unconscious foundation myths are evaluated for their effects on the training programmes. Ultimately, transparency in the distribution of power and democratic self-determination must prevail if scientific scrutiny and renewal of theoretical and clinical doctrine are to be maintained and advanced.
Shareholder Value and Group Analysis
Authors: Wuhrmann Sonja
Published: July 2003

The article suggests a group-analytic approach to explain the behaviour of groups in situations determined by economic forces beyond their control. Its starting point arises from two propositions: Aristotle's claim that all human beings are basically members of communities and pursue a common goal, namely to enable everyone to lead a `good' life, and the argument presented by the philosopher Robert Solomon, that modern management needs to respect ethical obligations. A practical example is given to illustrate the interaction between leadership responsibility and commercial considerations. This leads to the conclusion that group analysis is a useful method to better understand the pressures and insecurities that accompany globalization and to help people to overcome such anxieties.
A Crude Way of Loving: On Surviving the Trauma of Therapeutic Change with Borderline Patients in Group Psychotherapy
Authors: Kegerreis Duncan
Published: July 2003

This article traces the development of one patient in a psychotherapy group in which borderline pathology predominated. Dynamics specific to the therapeutic engagement of borderline patients and pressures experienced by the group analyst are illustrated. The author recommends particular adjustments in technique when conducting borderline groups.
The Coself, or Primary Syntheism
Authors: Abraham Ada
Published: July 2003

In all cultures and mythologies an allusion can be found to a primordial, chaotic state from which the world emerged, structured along clear-cut splits: sea-continent, day-night, earth-sky, man-woman - as if the collective unconscious tried to render intelligible and describable some universal secret, linked to conception and encrypted at once in the spirit of nature and the human psyche. In this article, I will try to defend the idea that every group situation provokes the immediate and massive emergence of a chaotic state, a pre-objectal stage where no clear distinction yet exists between subject and object, you and I.
The Group-As-A-Whole in the Interpretation
Authors: Battegay Raymond
Published: July 2003

Treating a therapy group as a whole neglects each member's individual experience and expectancies, especially when the group is considered from a psychological viewpoint. From a sociological-interactional perspective, however, the group can be seen as an entity, an interactional network. From this viewpoint we are interested in, for example, the quality and quantity of interactions in the members, the reciprocal feedbacks, etc. I speak of a `group dream', then, not because every member has had the same dream, but because a group participant's dream also reflects some or all other members' attitudes and behaviour patterns. Since a certain narcissistic-fusionary relationship is a preliminary stage to each object relation, some participants can speak to each other or the therapist to one member, and the others can profit from it. But it never goes so far that all group members would at any one moment have a unique group fantasy. On a higher level of relationship, transferences may occur in one or several individuals who may experience the group as a whole as a great caring mother But these transferences are different for each member and the therapist has to keep a bifocal attention on the individual members and the group situation.
The Group Ego-Skin
Authors: Anzieu Didier
Published: July 2003

This article gives an idea of a general approach of the application of groups to functions of the ego-skin. Its systematic nature, necessary for exploratory research, should be rendered flexible and nuanced as theory and experience are confronted. But an experience is instructive only if it is framed by an observation grid and by a body of hypotheses, proposed here for the first time. It is explained how the eight functions of the individual ego-skin are transposed to the group ego-skin and confirmed by patients' dreams about their families.
Borderline Personalities in Groups
Authors: Resnik Salomon
Published: July 2003

In this article, I try to develop the idea of understanding a borderline patient as a type of psychopath of the mind. As well as acting out feelings and thoughts, such a patient also tends to act inwardly, transforming thoughts into concrete inner objects, so that thinking becomes equated to mental action. My aim in this article is to describe and to interpret some aspects of borderline patients and narcissistic personalities in a group context.
The Creativity of Destructive Fantasies
Authors: Knauss Werner
Published: July 2003

Destructive fantasies are made unconscious in our culture compared to the lively symbolic exchange of such fantasies in Papua New Guinea. In groups unconscious destruction works as a dangerous force and can destroy the cohesion of the group, therefore they are kept anxiously unconscious. When they can be verbalized they become creative for the process of individuation of each group member. This paradox is described and theoretically discussed for the process of individuation within a cohesive group-analytic situation. Links to the concept of the anti-group and to a group-analytic theory of psychological development are made in the context of group-analytic research in a foreign culture.
The Hysterical Group and the Hysterical Analyst
Authors: Moss Eric
Published: July 2003

The group analyst occasionally encounters a form of resistance which could be called `hysterical states'. These states are group moments in which there is an avoidance of sexual material which is close to awareness but not actually out in the open. Such moments are characterized by mesmerizing story-telling that turns the whole group, including the analyst, into an audience. Everyone avoids the real function of the group, which is to acknowledge the sexuality and reflect upon it. Through self-monitoring and supervision, the analyst can regain his/her therapeutic stance and, as with other forms of resistance, interpret what is happening. If handled well, the sexual material is brought out for discussion, and there will be a marked increase in vitality among members.
Five Questions about Group Therapy in Long-Term Schizophrenia
Authors: Smith Jay
Published: July 2003

Group therapy has been demonstrated to be an effective treatment for individuals with long-term schizophrenic illnesses. However, therapists must be aware of the particular characteristics of these patients and modify their expectations, techniques and time scale of treatment accordingly. If this can be achieved, both patient and therapist may be surprised by how rewarding and helpful such a group may become.
Melt Compounding Based Rotational Foam Molding Technology for Manufacture of Polypropylene Foams
Authors: Pop-Iliev Remon , Park Chul B.
Published: July 2003

This paper is intended to provide an engineering understanding of the technological potentials for processing polypropylene (PP) foams in rotational foam molding. A process proposal, based on the melt compounding material-preparation approach, capable of producing completely foamed, single-layer, single-piece PP products in rotational foam molding, is disclosed in detail. It comprises dispersing a chemical blowing agent (CBA) in the PP matrix using a twin-screw compounder, pelletizing the obtained expandable composition, and then producing foams in an uninterrupted rotational foam molding cycle by using the pre-compounded foamable pellets. Several PP grades were deliberately selected to cover a wide range of melt flow rates (MFR), starting from 5.5 up to 35 dg/min. After the raw materials participating in the study were characterized using thermal analysis instrumentation, different foamable compositions were formulated in order to prepare both 3-fold and 6-fold foamable pellets from each PP grade. The optimal foam processing strategies were identified via a systematic experimental parametric search. Foams with the best cell morphologies were obtained out of the high melt strength PP grades. In addition, the experimental results revealed that the cell morphology of the processed PP foams is not as good as that of respective PE foams. However, the cell morphologies of the PP foams processed by using the melt compounding-based approach demonstrated significant improvements in comparison with those processed by using the dry blending-based approach.
Low Velocity Impact Studies on a 4-Ply Knitted Kevlar Fabric Reinforced Epoxy Composite
Authors: Lim C. T. , Tan V. B. C. , Ramakrishna S. , Lee J. B. K.
Published: July 2003

Four-ply knitted Kevlar fabric reinforced epoxy composites with three different stacking sequences were subjected to normal impact of up to 10 J using a hemispherical steel impactor. Similar modes of damage were observed from impacts on all three different stacking sequences where damage progressed from matrix cracking and fibre/matrix debonding at low impact energies to fibre breakage and eventual through-thickness cracks at higher impact energies. A critical mode of damage occurred at about 4.5 J where there was a sudden deterioration of impact resistance due to fibre breakage at the top and bottom plys. The only significant difference among composites of different stacking sequences subjected to low velocity impacts of similar magnitude was the propagation of through-thickness cracks at impact energy larger than 5 J.
Monitoring the Change of Viscosity during Cure Reaction of Epoxy Resins with Resin Position Sensor
Authors: Kim Jung Gon , Shin Kyoung Hoon , Ryu Ho Seok , Lee Jae Wook
Published: July 2003

It was required that the fundamental understanding of the resin’s rheological properties, such as viscosity, gel point and degree of cure are known during the processing of epoxy resin. In order to monitor these properties in-situ, a sensor system that can measure the viscosity changes during cure is needed. The resin position sensor (RPS) based on DC conductometry has been able to measure the ionic contents and electrical conductivity of most organic resins. Complex viscosity and electrical resistance were measured simultaneously during the cure of diglycidyl ether of bisphenol-A (DGEBA) epoxy resin with polyamide by mounting the RPS on the upper plate of rotational rheometer. To correlate the viscosity with the resistance, the rheological model for the viscosity changes and the electrical model for the resistance changes were used. From the results, the interrelationship of viscosity and resistance of epoxy resin could be confirmed.
Heat Shrinkable Polymer Blends Based on Grafted Low-Density Polyethylene and Carboxylated Nitrile Rubber
Authors: Mishra J. K. , Raychowdhury S. , Das C. K.
Published: July 2003

Heat shrinkability of a polymer, which depends on the elastic memory, was introduced into the system in the form of an elastomeric phase. The present study deals with the measurement of heat shrinkability of the blend of grafted low-density polyethylene and carboxylated nitrile rubber. The grafting materials used in this study were acrylamide, vinyl triacetoxy silane, and maleic anhydride. Coupling agents used were 4,4′-diamino diphenyl methane and 4,4′-diamino diphenyl sulphone. It was found from torque rheometry and swelling studies that the degree of interchain crosslinking was greatest when 4,4′-diamino diphenyl methane was used as a coupling agent in the maleic anhydride grafted low-density polyethylene, while it was lowest when 4,4′-diamino diphenyl sulphone was used as a coupling agent. Shrinkability of the high temperature stretched sample was more than that of room temperature stretched sample. It was found from XRD that the crystallinity of the stretched sample was more than that of original sample. It was observed from the high temperature DSC that the interchain crosslinking was responsible for the enhancement of the thermal stability of the sample. Interchain crosslinking between grafted polyethylene and elastomer improves the shrinkability. Probable interactions between the rubber and plastic phase were confirmed by IR spectroscopy.
Surface Roughness at the Melt/Gas Transition Sites of Gas-Assist Injection Molded Thermoplastic Composites
Authors: Liu Shih-Jung , Chang I-Ta
Published: July 2003

Gas assist injection molding has proven itself a breakthrough technology in molding thermoplastic composites. However, there are still unsolved problems that confound the overall success of this technique. This report was to study the surface roughness phenomenon occurring at the melt/gas transition sites of gas assist injection molded composite parts. The material used was 35% glass-fiber filled Nylon-6 composite. Experiments were carried out on an 80-ton injection molding machine equipped with a pressure-controlled nitrogen-gas injection unit. A spiral mold was used for all experiments. After molding, a roughness meter was used to measure the surface quality at the melt/gas transition sites of the parts. Various processing variables were studied in terms of their influence on the surface roughness of molded composites: melt temperature, mold temperature, melt filling speed, short-shot size, gas pressure, and gas injection delay time. A scanning electronic microscope was also used to characterize the surface roughness phenomenon of molded parts. It was found that the roughness at the transition sites was mainly caused by the fiber exposure of molded composites. Experimental investigation of a gas assist injection molding problem can help our understanding of the formation mechanism of surface roughness at the melt/gas transition sites, so that steps can be taken to improve the surface quality of molded parts.
Analytical Study of Clamped Steel Fiber Reinforced Aluminum Metal Matrix Composite Including Elasto-Plastic Behavior
Authors: Aslan Züleyha , Okutan Buket , Karakuzu Ramazan
Published: July 2003

The elasto-plastic behaviour of steel fiber reinforced aluminum metal matrix composite with five different orientations has been investigated, including the effect of single force. A composite beam with a rectangular cross section is fixed at one end and is bent by a transverse force P applied to the free end. To determine analytically, residual stresses and the expansion of plastic zone for different orientation angles a software program is developed and this program makes it possible to establish elastic region, plastic region, the distributions of the residual stress component, the distance between the free end and yield points for 0°, 30°, 45°, 60° and 90° orientation angles. To verify the analytical solutions, the sophisticated finite element code such as ANSYS 5.6 was used to perform numerical analyses.

The results from this analytical approach show that the composites with different orientation angles start yielding at the same distances from the free end at the upper and lower surfaces of the beam. In other words, the plastic region spread at the upper and lower surfaces together. It is also shown that the distance between plastic region and free end of the beam decreases due to increasing orientation angle.
A Stitched Blade-Stiffened RFI Composite Panel under Shear Loading
Authors: Qi B. , Ness R. , Tong L.
Published: July 2003

This report summarises the work conducted at the CRC-ACS investigating the effect of stitching on the post-buckling strength of a large blade-stiffened panel. These panels were manufactured by the resin film infusion (RFI) process. The skin was made of E-glass fibre and the stiffener made of carbon fibre fabrics. The stiffener was stitched onto the skin using two types of stitching patterns, straight and zigzag. The whole preform was then impregnated with Araldite LY556 epoxy resin during the RFI process. FE analysis was conducted for determination of the panel configuration and buckling behaviour. Shear testing was conducted on these panels and performance was evaluated. For comparison, unstitched panels were also manufactured and tested. The testing results clearly showed that stitching significantly improves post-buckling performance of large panels.
The Modified Quadric Surfaces Criterion for Composite Materials
Authors: Yeh Hsien-Liang , Yeh Hsien-Yang
Published: July 2003

A modification of the generalized quadric surfaces criterion for composite materials is presented in this paper. The unique features of the generalized quadric surfaces criterion are maintained. Thus, it is shown that the entire closed failure envelope of the modified quadric surfaces criterion is composed of piecewise quadric surfaces. And no biaxial tests are required for the determination of the coefficients about the stress interaction terms (i.e., σ iσ j).

Consider the fact that for isotropic and orthotropic materials loaded in principal material directions, there is no coupling between the in-plane and shear responses. To further simplify the use of failure criterion in engineering design, it is reasonable to assume the coefficients of in-plane and shear coupling terms to be zero in the modified quadric surfaces failure criterion.

The validity of the modified quadric surfaces criterion is examined with experimental results from off-axis uniaxial strength tests of unidirectional fiber composites, and angle-ply composite laminates. Comparisons were made with other well-known anisotropic failure theories and the generalized quadric surfaces criterion as well.
Creep and Durability of Environmentally Conditioned FRP-RC Beams Using Fiber Optic Sensors
Authors: Singhvi Aashish , Mirmiran Amir
Published: July 2003

Accelerated environmental conditioning increases creep rate of FRP bars and results in 2%-3% moisture absorption. Presence of salt in the solution does not affect creep rate of FRP-RC beams or moisture absorption of FRP bars. Effect on strength and stiffness of FRP is about 3% for saline solutions and none for moisture. Environmental conditioning lowers post-cracking stiffness of the beams due to stiffness degradation of FRP and loss of bond between FRP and concrete. Fiber optic sensors are less sensitive than foil gages to temperature effects, but must be handled properly during construction and secured carefully against harsh environments.
Thermal Elastic-Plastic Stress Analysis on Simply Supported Aluminum Metal-Matrix Composite Laminated Plates
Authors: Sayman Onur
Published: July 2003

In this study, thermal elastic-plastic stress analysis is carried out on simply supported symmetric cross-ply (0°/90°)2 and angle-ply (30°/-30°)2, (45°/-45°)2, (60°/-60°)2 aluminum metal matrix laminated plates. Tsai-Hill Criterion is used as a yield criterion. Differential equations are solved with a sufficiently large number of integration intervals of the temperature. The intensity of the residual stress components in the cross-ply laminated plate are higher than those in the angle-ply laminated plates. The residual stress component of the shear stress alone in the angle-ply laminated plates is different from zero.
Effect of Hygrothermal Aging on the Fracture of Composite Overlays on Concrete
Authors: Lyons Jed , Laub Dorothy , Giurgiutiu Victor , Petrou Michael , Salem Hanadi
Published: July 2003

This research assessed the effects of elevated temperature and humidity exposures on the durability of fiber reinforced epoxy composite overlays on concrete substrates. Modified double cantilever beam samples were used to determine the Mode I strain energy release rate of the composite-to-concrete bond after exposure to temperatures of 23°, 60° or 100°C, humidity levels of 50 or 95% RH, and times up to 40 days. The only statistically significant degradation in toughness was observed after exposure to the 100°C, 95% RH environment. However, chemical changes in the matrix occurred during this extreme exposure condition that may not represent the in-service aging of composite-repaired concrete structures.
A Comparative Study of Finite Element Models for the Bonded Repair of Composite Structures
Authors: Odi Randolph A. , Friend Clifford M.
Published: July 2003

In this paper, the issues surrounding the repair of composite structures have been reviewed. This review has highlighted the need for the development of analytical techniques for the design of repair schemes. The finite element method is shown to be an appropriate candidate for such a task. Modelling approaches for adhesively bonded joints are well documented in the literature. Although bonded joints and repair joints share similar features, designing repairs and bonded joints are two different tasks. The open literature on modelling approaches specifically for repair joints is not abundant. Furthermore, there is no evidence of any studies undertaken with the specific aim of looking at the fundamental aspects of applying the finite element method to the analysis of bonded repairs to composite structures.

This paper highlights the philosophy behind these modelling approaches that have been used or suggested in the past. These approaches have been compared in order to gain a better understanding of the current state of affairs and how they relate to each other.
In-Plane Permeability of Stitched MMWK Laminates in Resin Transfer Molding
Authors: Chiu C. -H. , Cheng C. -C.
Published: July 2003

Resin Transfer Molding (RTM) involves the injection of liquid resin into a closed mold preloaded with dry preforms. For planar composite structures, the in-plane permeability should be determined prior to the injection process in order to predict the fluid flow and fill time progress. In this work, the in-plane permeability of multi-layer multi-directional warp knit (MMWK) laminates stitched using Kevlar fiber were measured using radial flow visualization experiments. The visualization demonstrated that the in-plane permeability of MMWK laminates is highly anisotropic and significantly influenced by the Kevlar stitches. Results showed that the major principal permeability, k x, decreased with an increase in stitch density. Although the stitches resulted in an increase in minor principal permeability, k y, it seems that the increase in stitch density did not result in an obvious change in k y.
Devolatilization of Polymers by Diffusion and Foaming
Authors: Gestring Ingo , Mewes Dieter
Published: July 2003

Devolatilization is a key step in polymer processing. Low-molecular-weight components are removed from a polymeric system. The transport of these components takes place by diffusion to the polymer-vapor interface. This interface can be formed by free surfaces of single-phase polymer melts or by bubbles. In this study the transport with and without bubble nucleation is investigated independently from each other in a specially designed apparatus.

The mass transport in thin films and in rotating pools with surface renewal is measured. High surface renewal rates and thick films enhance the mass transfer for single phase flow. For two phase flow and devolatilization the conditions for bubble nucleation and foam formation are investigated. The bubble nucleation is observed in the rotating pool in the area of high shear velocity.
Elongational Effects of Die Flows: Pressure Distribution and Shape Prediction
Authors: Sun J. , Waucquez C. , Rubin Y.
Published: July 2003

There are many industrial applications in which shear and extensional behaviors of the material both play a role. This is true, for example, for flows in converging channels or flows in abrupt contractions typical of cable coating, fiber spinning or indeed flows in many plastics and rubber extrusion dies.

Viscoelastic flow simulation has made it possible to predict these effects, at least qualitatively. Numerical simulations using a 3-mode PTT model reported here show a good quantitative agreement with experimentally measured pressure drops over a range of flow rates for both a short and a long conical capillary die.

While this approach is physically meaningful, convergence at high Weissenberg number remains a challenge for the scientific community. This fact can sometimes justify the call for simpler, qualitative engineering approximations. By adding in the flow equations the dependence of the viscosity function on the third invariant of the rate of deformation tensor, it becomes possible to consider some effects of extensional viscosity in axisymmetric and 3D flows.

We observe an increase in the pressure drop and the onset of recirculation patterns. We present numerical simulations of flow in a converging cone capillary and compare the results with available experimental data. We include simulation results for 3D die swell which show the influence of this extensional effect.
Ultrasonic Monitoring of Nozzle and Cavity during Injection Moulding
Authors: Brown E. C. , Dawson A. J. , Coates P. D.
Published: July 2003

Ultrasonic techniques are recognised as powerful sources of process information. Transducers are applied directly, are non-invasive, yet interrogate the entire melt cross-section, while data are available real-time. During injection moulding, two zones are considered: nozzle and cavity.

In the nozzle, ultrasonic velocity measurement provides temperature and pressure information. Mean temperatures not observed by other techniques are detected. Previous extrusion based experience is used to address issues of high temperature transducer operation. In the cavity, changes in reflection coefficient and ultrasonic velocity provide information on mould filling and part cooling. Various mould geometries are monitored using a number of ultrasonic transducers.
An Elastic-Plastic Stress Analysis on a Thermoplastic Composite Beam of Arbitrary Orientation Supported from Two Ends Acted upon with a Force at the Midpoint
Authors: Sayman Onur , Esendemir Ümran
Published: July 2003

An analytical elastic-plastic stress analysis is presented for a low density polyethylene thermoplastic composite reinforced by woven steel fibers supported at the ends acted upon with a force at the midpoint. The expansion of the plastic region and the residual stress component of σ x are determined for θ = 0°, 15°, 30° and 45° orientation angles. Plastic yielding occurs for 0° and 45° orientation angles on the lower and upper surfaces of the beam at the same distances from the midpoint. But, it starts first at the lower surface for 15° and 30° orientation angles. The residual stress components are obtained after releasing the external force. The residual stress component of σ x is maximum at the lower and upper surfaces. However, the intensity of the residual stress component τ xy is maxiumu on or around the x axis of the beam. The beam can be strengthened by using the residual stresses.
Influence of Process Parameters on the Phenomenon of Stress Cracking during Hot Plate Welding
Authors: Potente H. , Schnieders J.
Published: July 2003

Heating experiments were carried out in order to investigate the significance of the different process parameters on susceptibility to stress cracking. With the help of wetting tests, different crack lengths were generated in the heated sheet and subsequently compared with the various process parameters by means of multiple regression analysis. Another focal point is the estimation of the normal stress difference (|σ x-σ y|)at each point of the specimen by means of 2D photoelastic stress analysis. In both cases the marked correlations between the process parameters and the phenomenon of stress cracking are recognisable, and the results can be used to minimise stress cracking.
On the Prediction of Crystallinity Distribution in Injection Molded Semi-Crystalline Thermoplastics
Authors: Guo Jianxin , Narh Kwabena A.
Published: July 2003

Injection molded semi-crystalline thermoplastic parts show variable morphologies across their thickness. Process parameters such as injection speed, mold temperature, and melt temperature, play an important role in forming these morphologies. The heat and shear history has a great effect on the crystallization process of the semi-crystalline plastics. In this study, different available crystallization models were used to predict the crystallinity distribution, and capabilities of the models compared. Based on the results from these models, a more realistic model, which considers stress relaxation during the crystallization process, is proposed.
Fiber Local Micro Buckling of Continuous Glass-Fiber Reinforced Rectangular Hollow-Cored Commingled Recycled, Plastic Extrusions under Bending
Authors: Zheng Zhiyin , Engblom John J.
Published: July 2003

The experimental results of fiber local micro-buckling and partial failure due to the fiber micro buckling of extruded continuous glass fiber reinforced hollow-cored recycled plastic lumber under four point bending are presented in the paper. The test specimens are commercially produced E-glass roving reinforced recycled HDPE extrusions (2.5″ by 3.5″ hollow-cored cross section and 42″ in length) with/without coupling agent and different color pigment. The test results show that the fiber micro buckling causes a significant drop in strength of the extruded lumber and subsequently causes the matrix cracking that will lead to the total structural failure. It becomes a concern for the continuous fiber reinforced plastic beams used in construction fields because most of them are under bending loads. The micro buckling occurs on the compressive half of the hollow beam when it undergoes bending loads. The critical compressive stress is reasonably close to the predictions of Rosen’s model if considering a factor of 0.63 as proposed by Hahn and Williams (1986). For the specimens without the additives and coupling agent, the results show no sign of fiber micro buckling though their strength is much lower than those with the additives and coupling agent. In addition, it is shown that the fiber micro buckling initiates the matrix longitudinal as well as latitudinal cracking.
Investigation of Vibration Behavior of Patched Edge-Cracked Composite Plates
Authors: Wang Wei-Chung , Chen Chien-Hua
Published: July 2003

In this paper, the vibration behavior of a clamped edge-cracked composite plate repaired by composite patching was investigated. Modal testing was first used to measure the natural frequencies and mode shapes of the composite plate before and after repair. The amplitude fluctuation electronic speckle pattern interferometry (AF ESPI) was also employed to find the real-time absolute whole-field displacement. Based on the results from those two methods, effects of different stacking sequences and numbers of layers of the patching on the vibration behavior of the composite plate were studied. It was found that the change of fiber orientation and the number of layers of the patching have more significant influence on the variation of mode shapes of higher modes.
Vibration and Damping Analysis of Laminated/Sandwich Composite Plates Using Higher-Order Theory
Authors: Makhecha D. P. , Ganapathi M. , Patel B. P.
Published: July 2003

In this paper, the effects of higher-order theory, that accounts for the realistic variation of in-plane and transverse displacements through the thickness, on the modal loss factors and natural frequencies of thick composite laminated/sandwich plates, have been studied. The formulation is based on finite element procedure using C0 eight-noded quadrilateral plate element. Further, the complex modulus of an orthotropic lamina is employed to model the damping effect. The significance of various higher-order terms considered in the model in predicting the vibration and damping characteristics are shown through the numerical studies. A detailed parametric study is also carried out to highlight the influences of ply-angle, aspect ratio, number of layers, and core to face thickness ratio for sandwich laminates on frequencies and system loss factors of composite laminates/sandwich plates.
Tensile Properties of Glass-Mat Reinforced Polycarbonate Toughened Epoxy Composite
Authors: Rajulu A. Varada , Rao G. Babu , Reddy R. Lakshminarayana , Balaji Perugu Jithendra , He Jiasong , Zhang Jun
Published: July 2003

Epoxy was toughened with polycarbonate in different proportions. Woven glass mat was reinforced into this matrix. The variation of tensile strength with varying mat content and polycarbonate content was studied. The tensile strength of the composites was found to be higher than that of the matrix. Further, the tensile strength of both the composite and the matrix increased with polycarbonate content of up to 10%, beyond which it decreased. The tensile strength for 20% volume content of the glass-mat was found to be maximum when reinforced in both epoxy and blend matrices.
Probabilistic Analysis of Creep of Metal-Matrix Composites
Authors: Mao Hongyin , Mahadevan Sankaran
Published: July 2003

In this paper, a probabilistic model is developed to evaluate the creep reliability of metal-matrix composites under constant loading. The scatter of fiber strength and the randomness in elastic moduli of the matrix and the fibers are incorporated into the model for failure prediction of the composite material due to creep. Time-dependent reliability is evaluated at different service life times. The effect of broken fibers on the failure of the composite is included. The first-order reliability method (FORM) is used to evaluate the reliability. The proposed probabilistic analysis of the composite due to creep is demonstrated with a numerical example. The effects of different random variables on the failure probability are investigated.