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This paper proposes a new design for line-start operation of synchronous reluctance motors. In the past years, synchronous reluctance motors have been studied by many researchers. Due to high efficiency, they have gained increasing interest because in the synchronous operation, there is limited losses in the rotor. On the other hand, line-start operation of the synchronous reluctance motors is an important challenge that can make this type of the motors popular in many applications. However, line-start operation techniques should not considerably affect the steady-state characteristics of the motor. In the proposed design, the arrangement, size and shape of the rotor conductor bars are designed based on the rotor magnetic circuit difference between induction and reluctance synchronous motors. Complete assessment of the motor parameters are examined using finite element analysis. The proposed structure improves the starting characteristics of the motor. Moreover, power factor of the proposed motor is slightly increased in comparison to that of conventional line-start synchronous reluctance motors. The results obviously show effectiveness of the proposed line-start operation strategy for the synchronous reluctance motors. Finally, experimental verification are also included to confirm the finite element analysis results. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the functional integrity of visual pathway in hypothyroid patients by pattern visual evoked potential (PVEP).Methods: We enrolled 36 female patients with history of hypothyroidism (18 overt and 18 subclinical) aged 20 to 60 years and 36 healthy women of similar age (control group). All subjects had a complete ophthalmic examination. For VEP testing, subjects were exposed to checks subtending a visual angle of 15 and 60 min of arc.Results: For the 15 min of arc check size, the mean P100 latency was significantly delayed (113 milliseconds (ms)) and amplitude significantly reduced (9.2 microvolts (µv)) in the hypothyroidism group compared with controls (109.6 ms and 11.6 µv, respectively). For this 15′ check size, the group differences were related to significantly increased latency and reduced amplitude of responses in the group with overt hypothyroidism compared with controls. There was no difference between the groups (hypothyroid vs control) with 60 min of arc check size. There was a significant correlation between severity of the disease and PVEP component.Conclusions: In conclusion, low levels of circulating hypothyroid hormone are associated with delay in the pattern VEP to small check sizes. This CNS involvement worsens in patients with greater severity and duration of hypothyroidism. [ABSTRACT FROM AUTHOR]

Background: To compare the accommodative amplitude (AA), facility (AF), and lag between dominant and non-dominant eyes. Methods: Seventy students [mean (SD) age: 21.2 (1.7) years, range 18-25] from Zahedan University of Medical Sciences were selected. Retinoscopy and subjective refraction was used to determine the refractive error. The hole-in-the card method was used to determine eye dominance. The accommodative amplitude (AA) was measured in the dominant and non-dominant eye using the push-up method, and accommodative facility (AF) using ±2.00 dioptre flipper lenses at 40 cm. Accommodative lag was determined using monocular estimate method (MEM) retinoscopy at 40 cm. Results: The right eye was dominant in 53 subjects (75.7 %). There was no significant difference in refractive error (sphere, cylinder, and spherical equivalent) between dominant and non-dominant eyes. The mean (SD) for the AA, AF, and lag in dominant eyes was 12.48 (2.56) dioptres, 12.45 (4.83) cycles per minute, and 0.80 (0.27) dioptres respectively. The mean (SD) for the AA, AF, and lag in non-dominant eyes was 12.16 (2.37) dioptres, 12.20 (4.88) cycles per minute, and 0.83 (0.28) dioptres respectively. The mean (SD) difference in AA, AF, and lag between dominant and non dominant eyes was 0.32 (0.75) dioptres ( P = 0.001), 0.25 (1.05) cycles per minute ( P = 0.04), and −0.02 (0.11) dioptres ( P = 0.10) respectively. The AA and AF was statistically better ( P < 0.05) in the dominant eye group than in the non-dominant eye group. These data provided little evidence of any difference in the accommodative lag between dominant and non-dominant eyes ( P > 0.05). Conclusion: The right eye was dominant in 76 % of subjects. Superior AA and AF was found in the dominant eye as determined by hole-in-the card method in young healthy adults, although these differences are perhaps not of clinical significance (<0.50 dioptres and <2 cycles per minute). [ABSTRACT FROM AUTHOR]