Analysis and Application of the Direct Flux Control Sensorless Technique to Low-Power PMSMs

In the field of sensorless control of permanent magnet synchronous motors (PMSMs), different techniques based on machine anisotropies have been studied and implemented successfully. Nevertheless, most proposed approaches extract the rotor position information from the measured machine currents, that, when applied to low-power machines, might require high-bandwidth current sensors. An interesting alternative is given by sensorless techniques that exploit the star-point voltage of PMSMs, such as the direct flux control technique. This work aims at analyzing the conditions of applicability of such technique by considering a more thorough description of the machine inductance matrix. After a comprehensive mathematical description of the technique and characterization of the machine anisotropy information that is extracted from the star-point voltage, simulation as well as experimental results conducted on a test machine are presented and discussed in order to validate the proposed theory

Are Pain Intensity and Pain Related Fear Related to Functional Capacity Evaluation Performances of Patients with Chronic Low Back Pain?

Introduction: Pain related fear and pain intensity have been identified as factors negatively influencing Functional Capacity Evaluation (FCE) performances in patients with CLBP. Conflicting results have been reported in the literature. The objective of this study was to analyze the relationships between pain intensity and pain-related fear on the one hand, and performances during an FCE on the other hand in two samples of patients with chronic low back pain (CLBP). Methods: Two cross sectional observation studies were performed with two samples of patients with CLBP (study 1: n = 79; study 2: n = 58). Pain related fears were operationally defined as the score on the Tampa Scale of Kinesiophobia in study 1, and the Fear Avoidance Beliefs Questionnaire (FABQ) in study 2. Pain intensity was measured with a Numeric Rating Scale in both studies. Avoidance behavior observed during FCE was in both studies operationally defined as the unwillingness to engage in high intensity performance levels of three different functional activities: high intensity lifting, prolonged standing in a forward bend position, and fast repetitive bending at the waist. Results: A total of 25 correlations between pain and pain related fear, and performance variables were calculated, out of which 7 were significant (p < 0.05). The strength of these significant correlations ranged from r = −0.23 to r = −0.50. Multivariate linear regression analyses revealed non-significant relationships in most instances. Pain and pain related fear contributed little if any to these models. Conclusions: The relation between pain and pain related fear and FCE performance is weak or non-existent in patients with CLBP

Psychopathology among homicidally bereaved individuals: A systematic review

In the literature on bereavement, claims are made that homicidal loss is associated with posttraumatic stress reactions, depression, and other severe mental health problems. It is surprising that only a few studies have investigated the nature and prevalence of emotional symptoms following homicidal bereavement and a reference to systematic, empirical research is seldom provided. This article reviews the available literature to investigate whether these claims have empirical evidence. Three databases were searched to identify relevant studies. This approach was supplemented with a bibliography search. Eligible studies included English-language peer-reviewed articles that assessed psychopathology in the homicidally bereaved, as defined in the Diagnostic and Statistical Manual of Mental Disorders. Of the 360 potentially relevant articles, 8 studies (13 references) met predefined inclusion criteria. Homicide-related psychopathology among the bereaved assessed in these studies includes posttraumatic stress disorder (PTSD), depression, complicated grief, and substance abuse. Prevalence of lifetime homicide-related PTSD varied from 19.1% to 71% across studies. Current PTSD varied between 5.2% and 6%. The reviewed literature was inconclusive regarding the course of symptoms over time and the severity of psychopathology among the homicidally bereaved, compared to individuals bereaved by other causes of death. A comparison of the nature and prevalence of psychopathology between studies was complicated by unequal sample sizes and type, recruitment strategy, study design, and time since loss. Limitations of the included studies are discussed, as well as implications for clinical practice, policy, and future research

Psychopathology Among Homicidally Bereaved Individuals: A Systematic Review

In the literature on bereavement, claims are made that homicidal loss is associated with posttraumatic stress reactions, depression, and other severe mental health problems. It is surprising that only a few studies have investigated the nature and prevalence of emotional symptoms following homicidal bereavement and a reference to systematic, empirical research is seldom provided. This article reviews the available literature to investigate whether these claims have empirical evidence. Three databases were searched to identify relevant studies. This approach was supplemented with a bibliography search. Eligible studies included English-language peer-reviewed articles that assessed psychopathology in the homicidally bereaved, as defined in the Diagnostic and Statistical Manual of Mental Disorders. Of the 360 potentially relevant articles, 8 studies (13 references) met predefined inclusion criteria. Homicide-related psychopathology among the bereaved assessed in these studies includes posttraumatic stress disorder (PTSD), depression, complicated grief, and substance abuse. Prevalence of lifetime homicide-related PTSD varied from 19.1% to 71% across studies. Current PTSD varied between 5.2% and 6%. The reviewed literature was inconclusive regarding the course of symptoms over time and the severity of psychopathology among the homicidally bereaved, compared to individuals bereaved by other causes of death. A comparison of the nature and prevalence of psychopathology between studies was complicated by unequal sample sizes and type, recruitment strategy, study design, and time since loss. Limitations of the included studies are discussed, as well as implications for clinical practice, policy, and future research

Alignment of safety and security risk assessments for modular production systems

AbstractIn order to ensure the safety and security of industrial systems with regard to all life cycle phases from development through operation to disposal, specific regulatory and normative requirements are imposed. Due to the digitalization, interconnection, and constantly increasing complexity of manufacturing systems in the context of Industrie 4.0, the manual effort necessary to achieve the required safety and security is becoming ever greater and almost impossible to manage, especially for small and medium-sized enterprises. Therefore, this paper examines the existing challenges in this area in more detail and gives an outlook on the possible solutions to ensure safety and security much quicker and with less manual effort. The overall vision is a (partially) automated risk assessment of modular systems with respect to safety and security, including the alignment of the corresponding processes from both domains and the formalization of the information models needed.</jats:p

The Psychological Inflexibility in Pain Scale (PIPS): Exploration of psychometric properties in a heterogeneous chronic pain sample

Psychological flexibility receives increasing attention as the overarching process in Acceptance and Commitment Therapy (ACT). This study investigates the psychometric properties of the Psychological Inflexibility in Pain Scale (PIPS), measuring “avoidance” and “cognitive fusion” with pain, in a heterogeneous clinical sample of 428 chronic pain patients from four rehabilitation centers. Furthermore, the relationship between the PIPS and mindfulness (Five Facet Mindfulness Questionnaire, FFMQ) as a theoretically related measure within ACT is explored. Confirmatory factor analyses replicated acceptable/good model fit and internal consistencies. In a subsample from two rehabilitation centers (n = 237), the PIPS showed moderate to high relationships with aspects of mindfulness, pain interference in daily life, pain disability and mental health, and small relationships with pain intensity and physical functioning. The avoidance subscale explained additional variance in outcome variables beyond the FFMQ, ranging from 4.5 to 15.8%. Outcomes support the psychometric properties of the PIPS in a heterogeneous chronic pain sample. The PIPS and FFMQ measure slightly overlapping, but distinct constructs, and can be used complementary to assess a broad range of processes within ACT. Potential problems with the cognitive fusion subscale are acknowledged for future researc

Measuring avoidance of pain: validation of the Acceptance and Action Questionnaire II-pain version

Psychometric research on widely used questionnaires aimed at measuring experiential avoidance of chronic pain has led to inconclusive results. To test the structural validity, internal consistency, and construct validity of a recently developed short questionnaire: the Acceptance and Action Questionnaire II-pain version (AAQ-II-P). Cross-sectional validation study among 388 adult patients with chronic nonspecific musculoskeletal pain admitted for multidisciplinary pain rehabilitation in four tertiary rehabilitation centers in the Netherlands. Cronbach’s α was calculated to analyze internal consistency. Principal component analysis was performed to analyze factor structure. Construct validity was analyzed by examining the association between acceptance of pain and measures of psychological flexibility (two scales and sum), pain catastrophizing (three scales and sum), and mental and physical functioning. Interpretation was based on a-priori defined hypotheses. The compound of the seven items of the AAQ-II-P shows a Cronbach’s α of 0.87. The single component explained 56.2% of the total variance. Correlations ranged from r=−0.21 to 0.73. Two of the predefined hypotheses were rejected and seven were not rejected. The AAQ-II-P measures a single component and has good internal consistency, and construct validity is not rejected. Thus, the construct validity of the AAQ-II-P sum scores as indicator of experiential avoidance of pain was supported