Transformer tank vibration modeling as a method of detecting winding deformations-part II: experimental verification

In Part I of the paper, a tank vibration model was proposed as a method to detect the winding deformations in power transformers. This model is incorporated in a model-based monitoring system for power transformers. In this paper, the experimental verification of the proposed model that calculates vibration on the transformer tank is reported. The model was validated in a 1500-kVA experimental transformer constructed as a reduced scale model of a 60-MVA 220-kV unit. In order to load the test transformer, the opposition method described in IEC 60076-2 Standard was used allowing to vary the load and power factor over a wide range. Sensors to measure vibrations and temperature were installed in the test transformer. The model was validated under different test transformer operating conditions. In order to verify the model's ability to detect failures, a deformation was provoked in the test transformer winding. Model predictions were compared with the measured vibration in that situation. The model has also been applied to four (30-40 MVA) grid transformers. Some results of this field validation are presented in this paper.     

99Tc(m)-MIBI scanning of the thyroid gland in patients with markedly decreased pertechnetate uptake

The prevalence of nontuberculous mycobacteria (NTM) isolated from the lower airways of adult cystic fibrosis (CF) patients appears to be increasing. Different centers of USA, England, Sweden and Ireland have reported a prevalence ranging from 1.5 to 19.5%. The aim of the present study was to investigate the presence of NTM in patients assisted at these centers. A total of 92 sputum specimens and/or gastric contents from 40 CF patients were studied. Ages of patients ranged from 4 months to 25 years. Samples were obtained during acute exacerbation or in routine check-up. Mycobacterium avium-intracellulare complex strains were isolated from six patients with moderate or severe clinical manifestations. Five of these patients were considered as being colonized by NTM. Active mycobacterial disease was diagnosed in one patient and he underwent treatment. The index of bacterial contamination of cultures was very high early along the study (57%), decreasing to 2.8% later due to a change in the methodology used in the processing of samples. It was concluded that the presence of NTM is relatively frequent in patients with CF, even in children with moderate or severe compromise, a fact which strongly suggests that NTM should be systematically searched for considering the possibility that the patients might develop active disease.     

Long-term precipitation rate statistics for north-east of Spain

Precipitation rates recorded in Barcelona, Spain, over a 20 year period have been processed, and the average annual cumulative distribution is presented. This distribution reflects the meteorological conditions for the North-East of Spain and agrees well with statistics obtained for certain parts of the North of Italy and Greece. The average worst-month distribution is also presented and is related to the annual statistics.     

Differential effects of avoidant and attentional coping strategies on adaptation to chronic and recent-onset pain.

Examined the effectiveness of attentional (AT) and avoidant (AV) coping strategies for somatic, behavioral, and psychological adaptation to clinical pain among 30 chronic (CP) and 30 recent-onset pain (RP) patients. It was hypothesized that RP Ss would demonstrate greater adaptation (lower anxiety, depression, pain severity, and somatization ratings and higher levels of social activity) when employing AV rather than AT strategies. CP Ss using AT strategies were predicted to demonstrate greater adaptation than CP Ss using AV strategies. Ss completed the Coping Scale (A. G. Billings and R. H. Moos, 1981) as well as parts of the SCL-90 (Revised) and the West Haven-Yale Multidimensional Pain Inventory (R. D. Kerns et al, 1985). Results support the hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contrast effects in attitude judgment: An examination of the accentuation hypothesis.

A common finding in attitude judgment is that attitude positions discrepant from an extreme judge's own position are judged as more discrepant than in fact they are. The 2 studies in this article suggest that these contrast effects may be due to accentuation phenomena, as outlined by H. Tajfel (see record 1958-04920-001). Judges may make more polarized pro/anti judgments if they perceive the attitude positions as also differing on an agree/disagree (peripheral) dimension and if the judgment dimension and the peripheral dimension are correlated. In Study 1, a survey was conducted of 290 members of the National Organization for Women and the Massachusetts Federation of Republican Women to test the hypothesis. Strong support was found for the accentuation explanation of contrast effects. To rule out an individual difference alternative explanation for these results, Study 2 with 44 undergraduates experimentally manipulated the salience of the agree/disagree peripheral dimension. Greater contrast was found when the dimension was salient. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Polyisobutene/polystyrene interpenetrating polymer networks: Effects of network formation order and composition on the IPN architecture

In order to improve polyisobutene (PIB) mechanical properties, a PIB network is combined with a polystyrene (PS) one into an interpenetrating polymer network (IPN) architecture. PIB network is formed by alcohol addition between the hydroxyl end groups of a telechelic dihydroxy-polyisobutene and a pluri-isocyanate. PS network is synthesized by free-radical copolymerization of styrene with divinylbenzene. Thus, the optimal synthesis conditions are determined by FTIR spectroscopy and the kinetics of the alcohol-isocyanate addition is studied in detail. A short kinetic study of the PS network formation inside the PIB network is also carried out. The highest degree of interpenetration is obtained by forming the PIB network first. The corresponding transparent IPNs exhibit two mechanical relaxations corresponding to those of PS and PIB enriched phases. However, mechanical properties of PIB networks are tremendously improved by the presence of a PS network in such IPN architectures.     

Reasons for staying alive when you are thinking of killing yourself: The Reasons for Living Inventory.

65 adults generated 72 distinct reasons for not committing suicide; these were reduced to 48 by factor analyses performed on 2 additional samples, and the items were arranged into the Reasons for Living Inventory (RFL), which requires a rating of how important each reason would be for living if suicide were contemplated. In addition, factor analyses indicated 6 primary reasons for living: Survival and Coping Beliefs, Responsibility to Family, Child-Related Concerns, Fear of Suicide, Fear of Social Disapproval, and Moral Objections. The RFL was then given to 2 additional samples, 197 Seattle shoppers (mean age 36 yrs) and 175 psychiatric inpatients (mean age 31 yrs). Both samples were divided into several suicidal (ideators and parasuicides) and nonsuicidal groups. Separate multivariate ANOVAs indicated that the RFL differentiated suicidal from nonsuicidal Ss in both samples. In the shopping-center sample, the Fear of Suicide scale further differentiated between previous ideators and previous parasuicides. In the clinical sample, the Child-Related Concerns scales differentiated between current suicide ideators and current parasuicides. In both samples, the Survival and Coping, the Responsibility to Family, and the Child-Related Concerns scales were most useful in differentiating the groups. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)