Active front-end rectifier modelling using dynamic phasors for more-electric aircraft applications

The More-Electric Aircraft (MEA) has become a dominant trend for next-generation aircraft. The Electrical Power System (EPS) on-board may take many forms: AC, DC, hybrid, frequency-wild, variable voltage, together with the possibility of novel connectivity topologies. To address the stability, availability and capability issues as well as to assess the performance of the power quality and transient behaviour, extensive simulation work is required to develop the EPS architectures. The paper develops a fast-simulation model of active front-end rectifiers based on the dynamic phasor concept. The model is suitable for accelerated simulation studies of EPS under normal, unbalanced and line fault conditions. The performance and effectiveness of the developed model have been demonstrated by comparison against time-domain models in three-phase and synchronous space-vector representations. The experimental verification of the dynamic phasor model is also reported. The prime purpose of the model is for the simulation studies of MEA power architectures at system level; however it can be directly applied for simulation study of any other EPS interfacing with active front-end rectifiers

Türkiye’de bulunan yoğun bakımlarda sabun, kağıt havlu ve alkol bazlı el dezenfektanı yeterli mi?: Phokai çalışması sonuçları

Introduction: Hand hygiene is one of the most effective infection control measures to prevent the spread of healthcare-associated infections (HCAI). Water, soap, paper towel and hand disinfectant must be available and adequate in terms of effective hand hygiene. The adequacy of hand hygiene products or keeping water-soap and paper towel is still a problem for many developing countries like Turkey. In this multicenter study, we analyzed the adequacy in number and availability of hand hygiene products.Materials and Methods: This study was performed in all intensive care units (ICUs) of 41 hospitals (27 tertiary-care educational, 10 state and four private hospitals) from 22 cities located in seven geographical regions of Turkey. We analyzed water, soap, paper towel and alcohol-based hand disinfectant adequacy on four different days, two of which were in summer during the vacation time (August, 27th and 31st 2016) and two in autumn (October, 12th and 15th 2016).Results: The total number of ICUs and intensive care beds in 41 participating centers were 214 and 2357, respectively. Overall, there was no soap in 3-11% of sinks and no paper towel in 10-18% of sinks while there was no alcohol-based hand disinfectant in 1-4.7% of hand disinfectant units on the observation days. When we compared the number of sinks with soap and/or paper towel on weekdays vs. weekends, there was no significant difference in summer. However, on autumn weekdays, the number of sinks with soap and paper towel was significantly lower on weekend days (p<0.0001, p<0.0001) while the number of hand disinfectant units with alcohol-based disinfectant was significantly higher (p<0.0001).Conclusion: There should be adequate and accessible hand hygiene materials for effective hand hygiene. In this study, we found that soap and paper towels were inadequate on the observation days in 3-11% and 10-18% of units, respectively. Attention should be paid on soap and paper towel supply at weekends as well

A rheological network model for the continuum anisotropic and viscoelastic behavior of soft tissue

The mechanical behavior of soft tissue demonstrates a number of complex features including nonlinearity, anisotropy, viscoelasticity, and growth. Characteristic features of the time-dependent and anisotropic behavior are related to the properties of various components of the tissue such as fibrous collagen and elastin networks, large proteins and sugars attached to these networks, and interstitial fluid. Attempts to model the elastic behavior of these tissues based on assumptions about the behavior of the underlying constituents have been reasonably successful, but the essential addition of viscoelasticity to these models has been met with varying success. Here, a new rheological network model is proposed using, as its basis, an orthotropic hyperelastic constitutive model for fibrous tissue and a viscoelastic reptation model for soft materials. The resulting model has been incorporated into numerical and computational models, and is shown to capture the mechanical behavior of soft tissue in various modes of deformation including uniaxial and biaxial tension and simple shear.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47943/1/10237_2004_Article_49.pd

Bedesten köyü folkloru.

Donated by Klaus KreiserReprinted from : Türk Folklor. Araştırmaları, No:208, 211, Kasım 1966, Şubat 1967

The effects of XPD /ERCC2, RAD51 and hOGG1 gene polymorphisms on overall survival of Turkish gastric cancer patients

Abstract Not Availabl

Buscke-löwenstein tümörü (dev kondiloma akuminata): Cerrahi eksizyon ile tedavi

Giant condyloma acuminatum is a rare sexually transmitted disease which primarily affects genital and perianal areas. Human papilloma virus (HPV) is the most common sexually transmitted disorder in young, sexually active populations in the USA and Europe. Giant condyloma acuminatum is a uniqe variant of condyloma acuminata, characterized by local aggressive behaviour despite benign histology. It carries a substantial risk of squamous cell carcinoma. Various treatments have been used, but response is often poor and recurrence rates high. We present a case of giant condyloma acuminata succesfully treated with surgical excision.Dev kondiloma akuminata özellikle genital ve perianal alanı tutan, nadir görülen ve cinsel ilişki ile bulaşan bir hastalıktır. Human papilloma virüs enfeksiyonu A.B.D. ve Avrupa'da cinsel aktif populasyonda en sık görülen cinsel yolla bulaşan hastalıktır. Dev kondiloma akuminata benign histolojik tipte olmasına rağmen lokal olarak agresif seyreden bir kondilom çeşitidir. Düşük de olsa skuamoz hücreli kanser gelişme riski taşır. Çok çeşitli tedavi yöntemleri geliştirilmesine rağmen yanıt genellikle düşük ve nüks sık izlenmektedir. Bu olgu sunumunda dev kondiloma akuminatalı bir hastanın cerrahi eksizyon sonrası başarılı tedavisi sunuldu