532 research outputs found
Green Wave Traffic Optimization - A Survey
The objective of this survey is to cover the research in the area of adaptive traffic control with emphasis on the applied optimization methods. The problem of optimizing traffic signals can be viewed in various ways, depending on political, economic and ecological goals. The survey highlights some important conflicts, which support the notion that traffic signal optimization is a multi-objective problem, and relates this to the most common measures of effectiveness. A distinction can be made between classical systems, which operate with a common cycle time, and the more flexible, phase-based, approach, which is shown to be more suitable for adaptive traffic control. To support this claim three adaptive systems, which use alternatives to the classical optimization procedures, are described in detail.
What do we really know about late-onset schizophrenia?
Actual knowledge on classical late-onset schizophrenia, i.e. the schizophrenic disorders with onset after age 40 years, is reviewed regarding incidence, symptomatology and course. As is shown, sound empirical knowledge is scarce. Reasons for this are, on the one hand, the conceptual and terminological confusion which has occurred internationally regarding this illness group, and, on the other hand, the methodological limitations of the empirical studies conducted on this clinical picture thus far. If we only draw onclassical late-onset schizophrenia, as originally defined by Bleuler, and primarily on methodologically sound studies, as well as on own studies, we can nevertheless conclude that the term "late-onset schizophrenia” could be omitted. Late-onset schizophrenia does not seem to be a distinct entity, but instead seems to belong to the same illness group as classical schizophrenia with earlier onset. Slight differences in symptomatology and course are probably due to unspecific influences of age. The markedly higher proportion of women among late-onset cases, as well as our finding that symptomatology and course of late-onset women are comparably poor, could possibly be explained by an effect of the female sex hormone oestradio
Family aggregation and risk factors in substance use disorders over three generations in a nation-wide study
OBJECTIVE: This nation-wide register-based study investigated how often substance use disorders (SUD) and co-morbid disorders occurred in affected families compared to control families.
METHOD: A total of N = 2504 child and adolescent psychiatric participants who were born between 1969 and 1986 and were registered in the Danish Psychiatric Central Research Register (DPCRR) had a mental disorder before the age of 18 and developed SUD at some point during their life-time. In addition, N = 7472 controls without any psychiatric diagnosis before age 18 and matched for age, sex, and residential region were included. Psychiatric diagnoses of the first-degree relatives were also obtained. A family load component was assessed.
RESULTS: SUD occurred significantly more often in case families than in control families. SUD risk factors included SUD, depression, anxiety disorders, personality disorders, or conduct disorders in the family. Furthermore, male sex, more recent year of birth, and living in the capital city of Copenhagen were also significantly associated with having SUD. The family load explained 30% of the SUD manifestation in the case-probands. The findings in the total SUD group were mostly replicated in the two major subgroups of pure alcohol or multiple substance use disorders.
DISCUSSION: These findings based on a very large and representative dataset provide additional evidence for the strong family aggregation and further risk factors in SUD. The pattern of risk factors is largely the same for the total group of SUD and the major subgroups of pure alcohol and multiple substance use disorders
An enhanced single gate driven voltage-balanced SiC MOSFET stack topology suitable for high-voltage low-power applications
Abstract In the fabrication of some high‐voltage low‐power applications, low cost is much concerned, and thus using silicon carbide (SiC) MOSFET stack consisting of series connected low‐voltage devices is preferred rather than using an expensive single high‐voltage device. Therefore, a cost‐efficient single gate driven voltage‐balanced SiC MOSFET stack topology is proposed in this paper, where only some passive components are equipped with the stack. With a concept of single gate driver, the gate driver design of an SiC MOSFET stack is simplified. With an automatic balancing circuit which operates well with the sequential lagging single gate driver, good voltage balancing of SiC MOSFETs in the stack is realized without causing much extra loss and no additional active control is required. The working principle is illustrated in detail and the parameter selection together with design consideration is presented. Next, this topology is compared with RCD snubber method and active delay adjusting method to better illustrate its advantages. Finally, in a typical high‐voltage low‐power application, auxiliary power supply, the simulation and experimental results further verify the effectiveness of the proposed topology
Modeling and Operation of Series-Parallel Resonant Load in Industrial RF Dielectric Heating Application
Evaluation of In Situ Thermomechanical Stress-Strain in Power Modules using Laser Displacement Sensors
Four-switch Class-PN Power Amplifier for High Power Handling Capability in Wireless Power Transfer
- …