The analysis of different techniques for speed control of permanent magnet synchronous motor

U radu se predstavljaju tehnike reguliranja brzine primjenom proporcionalnog integrala (PI), derivacije proporcionalnog integrala i fuzzy logike u pogonu sinkronog motora s permanentnim magnetima. PI i PID regulatori zahtijevaju precizni linearni matematički model sustava. S druge strane, FL zahtijeva lingvistički opis sustava. Analizirana je dinamička reakcija PMSMa na regulatore pri različitim opterećenjima. Uspoređena je učinkovitost reguliranja fuzzy logikom i uobičajenim načinima pomoću PI i PID. FL regulatori su reagirali bolje od uobičajenih tehnika pri prelaznim uvjetima opterećenja te postigli bržu regulaciju.This paper presents the use of proportional integral (PI), proportional integral derivative (PID) and fuzzy logic (FL) speed controller techniques in the permanent magnet synchronous motor (PMSM) drive. PI and PID controllers require precise linear mathematical model of the system. On the other hand, FL needs linguistic description of the system. The dynamic response of PMSM with the controllers was studied under different load disturbances. The effectiveness of the fuzzy logic controller was compared with the conventional PI and PID controllers. The FL controller responded better than conventional techniques under transient load conditions and also achieved faster settling response

Elderly and aged asthma have different characteristics: results of a multicenter study

Background/aim: Characteristics of asthma in the elderly population is not well-known. The aim of the present study was to evaluate asthma in the elderly population, to compare disease characteristics between patients diagnosed <60 (aged asthma) and ≥60 (elderly asthma) years of age. Materials and methods: The study was a prospective, multicenter, cross-sectional type. A questionnaire was filled out to patients 60 years of age and over, that have been followed for asthma for at least 3 months. Asthma Control Test (ACT), eight-item Morisky Medication Adherence Scale (MMAS-8) was filled out, inhaler device technique was assessed. Results: A total of 399 patients were included from 17 tertiary care centers across the country. Mean age was 67.11 years and 331 (83%) were female. The age at asthma diagnosis was ≥60 in 146 (36.6%) patients. Patients diagnosed ≥60 years were older (p < 0.001), had higher education level (p < 0.001), more commonly had first-degree relative with asthma (p = 0.038), asthma related comorbidities (p = 0.009) and accompanying rhinitis/rhinosinusitis (p = 0.005), had better asthma control (p = 0.001), were using less controller medications (p = 0.014). Inhaler technique was correct in 37% of the patients with no difference in between the groups. Treatment compliance was better in elderly asthma patients (p < 0.001). In the multivariate logistic regression analysis, having well-controlled asthma (odds ratio = 1.61, CI = 1.04-2.51), and high medication adherence rate (odds ratio = 2.43, CI = 1.48-4.0) were associated with being in the elderly asthma group. Conclusion: The characteristics of asthma are different among patients aged 60 years and over which seems to be related to onset age of asthma. In our cohort, the elderly asthma patients had higher education level, and treatment adherence and asthma control was better. Patients diagnosed ≥60 years of age did not have more severe disease

Variations in abundance and diversity of phytoplankton in the surface waters of the Golden Horn Estuary (Sea of Marmara)

The abundance pattern and species diversity of phytoplankton in the surface waters of the Golden Horn Estuary were investigated between August 2011 and July 2012 in relation to environmental factors. Seventy-eight phytoplankton taxa (38 diatoms, 30 dinoflagellates and 10 phytoflagellates) belonging to eight taxonomic classes were identified in bottle and net samples. Phytoplankton abundance increased in spring and summer (from March to August) and reached its highest (10,429 x 10(3) cells L-1) during the bloom of Heterosigma akashiwo (Raphidophyceae) in the middle and upper estuary in late May. In general, phytoplankton abundance was higher in the middle estuary indicating more suitable conditions for phytoplankton growth, while species richness and diversity was higher in the lower estuary. The most abundant species were Skeletonema marinoi and Thalassiosira sp. among diatoms; Scrippsiella trochoidea among dinoflagellates; Plagioselmis prolonga and Heterosigma akashiwo among phytoflagellates. Diatoms were more abundant in the lower and middle estuary, while dinoflagellates and phytoflagellates in the upper estuary. The main factors causing the spatio-temporal variation of phytoplankton in the study area were temperature, salinity, water transparency and nutrients. Water transparency in the upper estuary is mostly influenced by organic and inorganic matter carried by two streams. As a result, this area should be considered a potential risk area for future algal blooms