Virtual Machining: Capabilities and Challenges of Process Simulations in the Aerospace Industry

AbstractMilling processes for the manufacturing of parts for aerospace applications can be influenced by various effects. When machining structural parts with high material removal rates, the stiffness of the machine tool can be a limiting factor because chatter vibrations. Additionally, vibrations of thin-walled structures, e. g., the blades of impellers or turbines, can lead to chatter vibrations and surface location errors. Thermo-mechanical deformations are another cause for violations of given shape tolerances. Geometric physically-based process simulations can be used to analyze milling processes with regard to these effects in order to optimize the process parameters. In this paper, an overview of several applications of a geometric physically-based simulation system for analyzing different effects during milling processes is presented. Depending on the relevant effects, process forces, the dynamic behaviour of the tool-spindle-machine system, vibrations of workpieces and fixture systems, as well as thermo-mechanical deformations are calculated

Implementing street triage: a qualitative study of collaboration between police and mental health services.

BACKGROUND: Street Triage is a collaborative service between mental health workers and police which aims to improve the emergency response to individuals experiencing crisis, but peer reviewed evidence of the effectiveness of these services is limited. We examined the design and potential impact of two services, along with factors that hindered and facilitated the implementation of the services. METHODS: We conducted 14 semi-structured interviews with mental health and police stakeholders with experience of a Street Triage service in two locations of the UK. Framework analysis identified themes related to key aspects of the Street Triage service, perceived benefits of Street Triage, and ways in which the service could be developed in the future. RESULTS: Stakeholders endorsed the Street Triage services which utilised different operating models. These models had several components including a joint response vehicle or a mental health worker in a police control room. Operating models were developed with consideration of the local geographical and population density. The ability to make referrals to the existing mental health service was perceived as key to the success of the service yet there was evidence to suggest Street Triage had the potential to increase pressure on already stretched mental health and police services. Identifying staff with skills and experience for Street Triage work was important, and their joint response resulted in shared decision making which was less risk averse for the police and regarded as in the interest of patient care by mental health professionals. Collaboration during Street Triage improved the understanding of roles and responsibilities in the 'other' agency and led to the development of local information sharing agreements. Views about the future direction of the service focused on expansion of Street Triage to address other shared priorities such as frequent users of police and mental health services, and a reduction in the police involvement in crisis response. CONCLUSION: The Street Triage service received strong support from stakeholders involved in it. Referral to existing health services is a key function of Street Triage, and its impact on referral behaviour requires rigorous evaluation. Street Triage may result in improvement to collaborative working but competing demands for resources within mental health and police services presented challenges for implementation

Depression after myocardial infarction is a risk factor for declining health related quality of life and increased disability and cardiac complaints at 12 months

OBJECTIVE: To study the prospective effects of post‐myocardial infarction (MI) depressive disorder on health status, including self reported cardiac symptoms, disability, and health related quality of life, at 12 months after MI while controlling for cardiac condition and health status at three months after MI. METHODS: Longitudinal study of a cohort of 468 adults with MI recruited from four hospitals in the north of the Netherlands between September 1997 and September 2000. Assessment of depressive disorder in the year after MI according to International classification of disease, 10th revision criteria. Assessment of health status at three and 12 months by the RAND 36 item health survey, the health complaints scale, self rated cardiac complaints, and disability. RESULTS: Patients with post‐MI depressive disorder were more likely than those without to have poor quality of life, more health complaints, more cardiac complaints, and more disability at 12 months' follow up. In multivariate analyses adjusted for cardiac condition, health status at three months, age, sex, and pre‐MI depression, the prospective association of post‐MI depression with poor health status remained for most of the indicators. Severity of the post‐MI depression further contributed to aspects of poor health status. CONCLUSIONS: In a prospective study design, post‐MI depression had strong effects on poor health status exceeding the effects of cardiac condition and its short term consequences. Efforts to improve health status after MI should therefore include standard assessment and guideline based treatment of post‐MI depressive disorder

Training primary-care physicians to recognize, diagnose and manage depression:does it improve patient outcomes?

Background, We developed a comprehensive, 20-hour training programme for primary-care physicians, that sought to improve their ability to detect, diagnose and manage depression. We evaluated the effects of physician training on patient outcomes, using a pre-post design. Methods. In the pre-training phase of the study, we sampled 1834 consecutive patients of 17 primary-care physicians and evaluated 518 of these patients for the presence of depression. We measured outcomes of all patients with depression at 3 months and 1 year. The outcome measures were: severity of psychopathology; duration of depressive episode; and level of daily functioning. After the 17 physicians completed the training, we drew a new sample from their practices (498 of 1785 consecutive patients were evaluated for depression) and measured outcomes for the depressed patients. Results. We found an effect of the training on short-term outcome, particularly for patients with a recent-onset depression. At 3-month follow-up depressed patients whose physicians had received training had less severe psychopathology and patients with recent-onset depression also showed higher levels of daily functioning than patients of the same physicians prior to the training. The patients with a recent-onset depression that was recognized by trained physicians had shorter depressive episodes, but this was not statistically significant. At 1-year follow-up, all training effects had faded away. Conclusions. Training primary-care physicians to recognize, diagnose and manage depression can improve short-term patient outcomes, especially for patients with a recent onset of depression. Patients suffering from a recurrent or chronic depression may need more specific interventions, both for acute treatment and long-term management

Clinical effects and treatment outcomes of long-term compulsory in-patient treatment of treatment-resistant patients with severe mental illness and substance-use disorder.

BACKGROUND: The treatment of homeless dual-diagnosis patients (i.e., those with severe mental illness and substance-use disorder) is difficult and often fails. For patients in the Netherlands who had not responded to earlier voluntary and compulsory treatment, a new treatment facility - Sustainable Residence (SuRe) - was developed to offer long-term compulsory in-patient treatment. AIM OF THE STUDY: To study patterns of changes in clinical and functional outcomes during treatment at SuRe and how these relate to eventual treatment outcome. METHODS: On the basis of the intensity of care needed after four years, three groups of patients were distinguished (total n = 165): those discharged to a less restrictive and less supportive setting (n = 70, 42%), those still hospitalized at SuRe at the end of the four-year study period (n = 69, 42%) and those referred to a more appropriate setting (n = 26, 16%). Random coefficient analysis was used to examine differences between groups regarding changes in clinical and functional outcomes during treatment. During treatment, outcomes were monitored using Routine Outcome Assessment. RESULTS: All three groups made small but significant improvements on global psychosocial functioning, distress and therapeutic alliance (effect sizes (ES) 0.11 to 0.16 per year). Patients who were discharged to a less restrictive setting showed small to moderate improvement in risk to self and others, psychiatric symptoms, and skills for daily living (ES 0.19-0.33 per year and 0.42-0.73 for their mean 2.2-year treatment period). Patients remaining at SuRe showed a small increase in risk to self (ES 0.20 per year; 0.80 for their treatment period of four years or more). Oppositional behaviour was consistently greater in referred patients than in the other groups (ES 0.74-0.75). CONCLUSION: Long-term compulsory treatment appeared to have helped improve clinical and functional outcomes in a substantial proportion (42%) of previously severely dysfunctional, treatment-resistant dual-diagnosis patients, who could then be discharged to a less restrictive and less supportive environment. However, risk-to-self increased in a similar proportion. A smaller number of patients (16%) showed marked oppositional behaviour and needed a higher level of care and protection in another facility

Help-seeking behaviour of hearing-impaired persons aged >= 55 years; Effect of complaints, significant others and hearing aid image

Objective-To determine factors influencing help-seeking behaviour in hearing-impaired persons aged greater than or equal to 55 years. Material and Methods-The study comprised 1,419 persons (480 females, 939 males) aged greater than or equal to 55 years who participated voluntarily in a driving test. Pure-tone audiometry was performed in all subjects. Participants without a hearing aid with an average hearing loss of greater than or equal to 30 dB in the better ear for the frequencies 0.5, 1, 2 and 4 kHz were asked how they perceived their hearing by means of a structured questionnaire. The questionnaire provided insight into why some hearing-impaired people seek help from a general practitioner (GP) and others do not. Four factors were examined. Results-A total of 483/1,419 (34%) participants tested had a hearing loss exceeding 30 dB. Fewer than half of these had visited their GP with complaints of hearing impairment. Of those who had not sought help from a GP, 57% nevertheless judged their hearing as poor. Social pressure exerted by significant others was less in the non-consulters group. Hearing aid image did not differ significantly between the two groups. Conclusion-The help-seeking behaviour of hearing-impaired elderly people is related to the degree of hearing disability and the social pressure exerted by significant others as well as the willingness to try hearing aids

Effects on depression pharmacotherapy of a Dutch general practitioner training program

Background: General practitioners' (GPs) ability to recognize, diagnose and treat depression improved significantly after a comprehensive, 20-h training programme. This study aims to evaluate in more detail the effects of the training on GPs' pharmacotherapy of depression and related issues. Methods: A pretest-posttest design was used. Both in the pre- and post-training phase, a sample was drawn from consecutive patients of the 17 participating GPs. In the pre-training phase we identified a sample of 31 cases with an ICD-10 depression who received an antidepressant from their GP. The sample was followed for I year. Outcome measures were: type of antidepressant, dosage, duration and number of target instructions given by the GP. Then we trained the GPs. In the post-training phase, we identified a new sample (n = 47) from their practices and measured the same outcomes. Results: Improvements were seen in choice for modern antidepressant, adequate dosage, adequate duration, and number of target instructions given. Limitations: Observed changes can be due to a period effect, inherent in a pre-post design. Conclusions: A post-academic hands-on training of GPs can improve depression pharmacotherapy according to clinical guidelines with respect to choice of a modern antidepressant, adequate duration and psychoeducation. (C) 2002 Elsevier Science B.V. All rights reserved