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The induction heating principle has been successfully introduced for about 20 years in domestic cooking appliances. The technical developments now concern the improvement of the current appliances and the introduction of new functions. So, one tendency is the design of multiwinding induction coils that are very adaptive concerning the shape and the power capability. This paper describes different original converter topologies designed to supply multiwinding coils, and, in addition, multicoil systems. The proposed topologies are based on particular use and associations of zero-voltage switching series-resonant converters. They are all characterized by a frequency-synchronized operating mode, in order to prevent any acoustic harm that could result from beating frequency-interferences. Index Terms--Frequency-synchronized power converter, induction heating, mnitiwinding induction coil, zero-voltage switching (ZVS) resonant power converter.

Power-factor-corrector (PFC) converters are now commonly used in low-power supply systems connected to ac networks. In addition to their basic PFC properties, they constitute the best technical solution to directly obtain the compatibility with a large range of ac voltages provided by different distribution networks around the world (typically, from 85 to 265 V rms). It is the main application of these converters. This function is achieved with an additional cost and volume, and this extra price to pay needs to be minimized. In this context, we first recall the main approaches of the design of conventional PFCs based on the boost converter topology. We emphasize the different critical points of the sizing that mainly concern the input choke and the silicon devices, in regard with the choice of the switching frequency. Few ways of improvement are then presented for these conventional PFCs. In a second part, always in the context of a large input voltage range, we consider the possibility to introduce the multi-level concept to reduce the input choke and filters. A solution using a multilevel Flying Capacitor Two-Cell converter is presented. It is shown that it can lead to a significant increase of the performances, with several options of sizing which can be suited to different requirements of the applications. Index Terms--Flying capacitor multicell converter, flying capacitors, multilevel converter, power-factor corrector (PFC).

In this paper, a nonintrusive method of current cartography inside a component is presented. The measurement of the current density in metallized film capacitors has numerous applications, including nondestructive testing, new component design, and validation of existing models on current distribution in capacitors. The method is based upon the measurement of the magnetic field created by a capacitor and the current density reconstruction by means of inverse problem methodology. The experimental setup comprises of a radio-frequency generator operating between 10 to 1000 MHZ, a near-field probe, an XY positioning table and a computer used for control and data acquisition. The first results confirm that, near some frequencies, the current density in the capacitor becomes nonhomogeneous and increases dramatically in some areas. Index Terms--Current cartography, current density reconstruction, magnetic field, metallized film capacitors.

76 university students responded to the Big Five Inventory, the Coopersmith Self-esteem Inventory, and rated how much they liked their first and middle names. Self-esteem positively correlated with scores on Agreeableness, Conscientiousness, and Extraversion and negatively with Neuroticism. Liking of one's first name correlated positively with scores on Conscientiousness only.

In this paper, we use an analytic model to calculate the losses in the metallized polypropylene film capacitors. The model is validated experimentally for capacitors having the same capacitance but different geometry. For each group of capacitors a temperature distribution in the roll is assumed with the aim of optimizing its thermal performance. It appears that the heating of a long capacitor is higher than that of an equivalent flat capacitor subjected to the same electric stresses. Index Terms--Equivalent series resistance, metallized film capacitors, optimization, polypropylene, thermal simulation.

In a study of the relationship between liking of personal names and personality factors, 98 college students responded to the NEO Five-factor Inventory and rated how much they liked 60 different male and 60 different female names on 7-point Likert scales. Each list consisted of equal numbers of common, less common, dated, and rare names. Over-all, common names were preferred to less common, dated, and rare names; less common names were preferred to dated and rare names; and rare names were least preferred of all. Persons who scored higher in Extraversion or Agreeableness tended to report liking more personal names. Higher Agreeableness or Extraversion scores were associated with stronger preferences for both common or less common names but not for dated or rare names. This latter relationship was observed for male and female personal names separately, as well as over-all.

125 university students indicated how frequently they performed 15 different personal habits that ordinarily are socially disapproved, e.g., nail-biting, nose-picking. They also responded to the Narcissistic Personality Inventory, the Social Desirability Scale, the Hong Psychological Reactance Scale, and the Social Interest Scale. The sexes differed in the frequencies with which they performed 6 of the 15 habits: men were more likely to pick their noses, to spit, to pick at scabs, or to repeat another's speech; while women were more apt to giggle or to pull hair. Persons who scored higher in Social Desirability tended to report less frequent performance of 12 of the 15 habits, while people who scored higher on Psychological Reactance tended to report more frequent performance of 8 of the 15 habits. A total habits score resulting from the sums of the frequency ratings of each of the 15 habits correlated positively with Psychological Reactance and negatively with Social Desirability. Scores on Narcissism and Social Interest did not significantly correlate with most habits. These results suggest that the approval motive and the disposition to resist limitation on one's freedoms may be factors affecting the rates of many of these personal habits.

This article reviewed the empirically based research on given names in several areas. The preferences for personal names were discussed in terms of variables such as the frequency of occurrence of the name and characteristics of the preferee such as sex, age, race, and religion. Liking of one's own names was related to some variables, including self-esteem. Unusual names apparently do have some effect, often a negative one. Personal names tend to have certain stereotypes associated with age, intelligence, attractiveness, and other dimensions. These stereotypes may in turn yield positive or negative consequences; however, their influence may be limited by other variables. The research on self-presentation by means of personal names and titles was also discussed. Additional topics covered included the effects of nicknames, sexually ambiguous or misleading names, being named for another person, and alphabetical position of surname., A study of personal names as a psychological variable indicates the influence of name on a person. Uncommon and sexually misleading names have a negative effect on a person, who are often teased because of their name. Negatively and positively stereotyped names related with intelligence, age, attractiveness or other things also have an influence on personality.

75 women and 64 men responded to the Coopersmith Self-esteem Inventory, the Manifest Anxiety Scale, and the Maudsley Obsessional-compulsive Inventory in addition to responding to a questionnaire on personal habits. The results indicated that more frequent hair-pullers and nervous twitchers scored lower on self-esteem and higher on anxiety. People who giggled and those who bit their fingernails more often scored higher on obsessive-compulsiveness. Self-reported gigglers were higher on manifest anxiety. If the criterion of self-assessed seriousness of the behavior problem was used, people who bit their nails, picked their noses, pulled their hair, chewed on objects, giggled, ground their teeth, twitched nervously, and picked at scabs scored lower on self-esteem. Higher manifest-anxiety scores were found among the people who regarded their nail-biting, hair-pulling, object-chewing, nervous twitching, or giggling as serious problems. Finally, people who regarded their nail-biting as more serious tended to have higher obsessive-compulsive scores. The results in general suggest that the frequency of several of these behaviors is anxiety-related and that it is the person's assessments of these behaviors as problems rather than simply their frequency that is related to higher anxiety and lower self-esteem.

This study explored the incidence of three personal habits and their correlates with popular tensional outlets. The 108 men and 202 women college students estimated how often they bit their fingernails, picked their noses, chewed on pencils or other objects, used specific tobacco products, used specific caffeine products, chewed gum, and exercised. Also, they rated their happiness on a seven-point scale in Likert format. The fingernail-biting incidence observed here was higher than was reported in previous samples of young adults, and more men than women were nail-biters. More men than women admitted to nose-picking; and about 61% of persons of either sex reported being occasional object-chewers. Men were more likely to exercise, use tobacco products, or consume iced tea than were women but were less likely to chew gum. The intercorrelations among the habits were not significant, and they were unrelated to lower self-reports of happiness. Both men and women who were object-chewers reported drinking greater amounts of cola beverages; otherwise, the relationships between these habits and product uses were not significant.

84 college students responded to Coopersmith's self-esteem scale, Moore and Barling's AIDS Questionnaire, and a background survey querying them as to their sex, race, religion, frequency of church attendance, marital status, college classification, and sources of their sex education. The results indicated that self-esteem scores correlated positively with having received sex education from the parents and negatively with not having received sex education from any of the listed sources. More frequent church attenders were more likely to have received sex education from their parents and to score higher in foreclosure status with regard to attitudes towards AIDS. Persons who scored higher on moratorium status for attitudes towards AIDS were less likely to have received sex education in high school, were more likely not to have received sex education from formal sources, and reported being less likely to use condoms.

This study examined the relationships that fathers' and mothers' interactive or disciplinary behaviors have with college students' Coopersmith Self-esteem Inventory scores, Social Desirability scale scores, and their retrospective perceptions of their parents' fairness (50 sons, 84 daughters). Sons with higher scores in self-esteem reported that their mothers were fairer, had more interest in their activities, and were less likely to use verbal put-downs (abuse). Daughters with high self-esteem reported both of their parents were more interested in their activities, used praise more often, and refrained from verbal abuse. Also, these daughters reported that their mothers were more fair and encouraged their independence more. Daughters who reported their fathers as being more strict had lower self-esteem scores. There was no evidence that spanking, grounding, scolding, or monetary rewards had any effect on children's self-esteem scores, whether these methods were used by mothers or by fathers. Both sons and daughters who perceived their parents as being more fair also saw them as being more interested, having used praise more often, and having been less likely to have used verbal abuse. Daughters were less likely to view either fathers or mothers as being more fair if they had used spanking, grounding, or scolding more, and had been over-all stricter. Sons who had less strict fathers or who had received monetary rewards from them tended to regard them as being more fair. Higher social desirability scores correlated with higher self-esteem of women. Also, women with these higher social desirability scores tended to report that both their fathers and mothers used scolding and grounding less often.

69 women and 42 men responded to the Coopersmith Self-esteem Inventory, the Revised UCLA Loneliness Scale, the Hong Psychological Reactance Scale, and the Famous Sayings test. Also, subjects rated their happiness using a Likert scale. Men scored significantly higher than did women on the UCLA Loneliness, Hostility, and Psychological Reactance measures, and lower on the Conventional Mores and Social Acquiescence measures. Loneliness scores positively correlated with Psychological Reactance scores and negatively with Self-esteem and Conventional Mores scores and with happiness self-ratings for both sexes. Men who scored higher on Psychological Reactance tended to score lower on Conventional More. Happiness ratings correlated negatively with Psychological Reactance for all subjects and positively with Conventional Mores for men subjects only. Women's self-esteem scores correlated positively with self-ratings of happiness and negatively with Psychological Reactance, Hostility, and Fear of Failure. Finally, women's Psychological Reactance scores correlated positively with those on Bass's Fear of Failure scale.

College students rated their own first, middle, and nicknames as to likability, attractiveness, and masculinity or femininity. They reported preferring their first names to their middle names and also found them more attractive. First names were better liked and found more attractive and sex-appropriate than were nicknames. Middle names were rated as more attractive and sex-appropriate than were nicknames. In general, persons who liked their first or middle names also rated them as more attractive and sex-appropriate. Liking of nicknames was related to their attractiveness.

The study of metallized capacitor behavior at high frequencies points out the presence of series and parallelresonances that could lead to oscillations, perturbations and additional losses in power electronics apparatus. Starting from an already established analytical model of this resonance, we propose a method to elaborate equivalent circuits suiting circuit simulators. These models should help further investigations on high frequency properties of decoupling and snubber capacitors in commutation cells. Index Terms--Capacitor impedance, circuit simulators, dielectric film, frequency-domain, high frequency models, magnetic components, metallized capacitor, time-domain.