Top PDF POWER TRANSFORMER TAP SWITCHING USING SEMICONDUCTOR DEVICES

POWER TRANSFORMER TAP SWITCHING USING SEMICONDUCTOR DEVICES

POWER TRANSFORMER TAP SWITCHING USING SEMICONDUCTOR DEVICES

Instead of using oil-immersed contact and complicated mechanical drive, a vacuum switch and bi- stable electromechanical actuator were used. These vacuum switches had the advantages of high power handling capability and long life, thus, suitable for the use of the selector. The proposed diverter, consisting of two solid-state switches, was to be connected between each of the selector output leads and in parallel with those two solid-state switches. A faster form of GTO assisted tap changer with the advantage of reduced transformer outages. The speed of the intended vacuum switch moving is now controllable, since fatigue in the stainless steel bellows is the prime limitation, and reverts to fast operation during a system fault.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Subjectivity is the process by which the researcher acknowledges, discusses, and takes into consideration experiences, beliefs, and assumptions that have framed the purpose for conducting the study and the researcher’s relationship to the study in terms of biases and perceived truths. 149,170 I must have acknowledged and understood through reflexivity, how my culture, race, and lived experiences impacted the development of inquiry into the phenomenon and my views and understanding of the subsequent findings. Subjective experiences are important components that justify use of the interpretivist approach to frame the study using CRT and discuss the data. Phenomena can only be understood within the context in which they are studied, 149 and experienced. As a PT, I have had experiences or subjective truths that were contextually the same as other PTs, because I have worked on an inpatient rehabilitation unit and treated persons with stroke. But being an AA, I have experienced what I perceived to be as racism, which may be the same for AAwS participating in the study. The key was not to impart my subjective truths during the research process, but to remain neutral so that I
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Attention-deficit/hyperactivity disorder (ADHD). The Child Behavior Checklist (CBCL; 1.5-5, 6-18; Achenbach, 1991; Achenbach & Rescorla, 2001) was completed by participants’ mothers at the initial and subsequent assessment points. The CBCL is a widely used 118 item parent rating scale used to assess the internalizing and externalizing symptoms of children. Items are answered using a 3-point Likert scale of “not true (0)”, “somewhat or sometimes true (1)”, and “very true (2).” It is broken down into individual symptom-specific scales, composite scores (internalizing, externalizing, and total problems) and also provides scales based on criteria from the Diagnostic and Statistical Manual (DSM-IV). For the DSM-based scales, there are raw scores as well as t-scores indicating severity. Overall, the CBCL was normed on a large, representative sample of children and adolescents, yielding high rates of reliability (r= 0.95; Nakamura, Ebesutani, Bernstein, & Chorpita, 2009). The ADHD scale of the CBCL has shown consistent reliability, discriminative validity, and convergent validity. Further, inter-rater reliability yielded similarly high consistency (r= 0.96; Nakamura et al., 2009). For the present study, the raw scores scale of DSM-ADHD was used to assess parent’s
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Photoluminescence data was collected using a Perkin Elmer LS 55 fluorescence spectrometer with a fiber optic attachment. This instrument is equipped with a xenon flash tube that travels along the path outlined in Figure 1.3. The spectral range of the excitation monochromator is 200-800nm, while the emission of the monochromator ranges from 200-900nm. The slit widths can also be varied from 2.5 to 15 nm for the excitation monochromator and between 2.5 and 20 nm for the emission monochromator. Results from the emission spectrum can be used in the Color Calculator program by Osram Sylvania to provide the CIE chromaticity coordinates within this dissertation 14 .
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

achievement is less likely to collaborate with an instructional coach and is less likely to support the utilization of the research-based instructional coaching model. Teachers who do not see the benefits of collaborating with an instructional coach will not tap into the resources offered by an instructional coach to improve their classroom instruction. The perceptions of teachers provide information and data that can impact how schools and school districts implement the instructional coaching model, how schools and school districts choose instructional coaches, and how schools and school districts should provide professional development for instructional coaches. Although instructional coaching typically involves only the adults in a school, it is the students who reap the benefits of an effective instructional coaching program in a school. Research from the Pathways to Success program on implementation rates after teachers attended a summer workshop that was followed-up with instructional coaching was 85% while earlier research concludes there is a less than 10% implementation rate following traditional workshops with no follow-up (Knight, 2005).
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Agrarians and Aristocrats (1981) offers a broad intellectual interpretation of the Jackson- era that characterizes the partisan divide as representative of a rift between two opposing “worldviews,” which Ashworth defines as an intellectual bundle “comprised of beliefs, fears, hopes, and a series of assumptions about government, society and the economy.” 7 The ideologies and policies of the opposing parties emanated from two conflicting perceptions of human society. The Democrats, he suggests, fundamentally conceived of the nation as a conglomeration of equal citizens, one whose proper function depended most fundamentally on vigilance against the natural tendencies of power units (“special interests,” perhaps?) to upset the healthy balance of equals. National republicans/Whigs, on the contrary, conceived of the nation as an organism, a body politic in the most literal sense, whose proper operation depended not on equality but rather on a diversity of roles served by inequality, insofar as nature doled out different capacities for different roles. The function of government was to harmonize the body, to, ideally, perfectly match one’s role to one’s capacity. Ashworth’s book makes a convincing case, for he is quite
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

countries and maximize the effectiveness of donor aid. The Paris Declaration is based on the recognition that partner country should take ownership of development strategies. A country partner has ownership when it takes the lead in determining the goals and priorities of its own development and set the agenda for how they are to be achieved. Strengthening the country's ownership represents a shift of power in the way aid relationship worked in the past, while underlining the need for mutual accountability (OECD, 2009). With strong ownership, the prospects for progress against other Paris Declaration principles improve. If partners “own” priorities, plans and programs, they are more likely to exercise effective leadership in getting donors to align to national
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Adiponectin, an adipokine secreted exclusively by adipose tissue, is decreased in obese subjects, likely increasing their propensity for the development of CRC. Several recent mechanistic studies using mice have made substantial advancements in our understanding of the role of adiponectin in CRC. For example, Saxena et al. examined the effect of adiponectin deficiency on chronic inflammation-induced CRC 53 . They reported that deficiency of adiponectin results in more severe symptoms along with a greater number and larger area of tumors that included higher immune cell infiltration and inflammation compared to wild-type mice 53 . Adiponectin knockout mice also
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

qualities of the second half of the B section melodic material (mm. During the second statement of B, Toch replaces wind sonorities with percussion. The rhythm on beat 2 in measure 134 i[r]

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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

university may have more funding within an individual state, resources are relative to other universities on a national scale. The research, showing longer time to degree for students at less selective institutions could be attributed to declining resources such as fewer course offerings, and also that students attending this type of institution spent time outside school in part or full time employment. The data is limited by the follow-up data collected for the NELS, which ended eight years after high school graduation and may have confounded the data and influenced the results. A more controversial issue with the study is their method of using US News and World Report rankings to identify the top public and private universities and liberal arts colleges. Since the US News rankings are typically made by college and university presidents or their staff, the selections may be unduly influenced by reputation and subject to inconsistent research methods when measuring data.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Participants responded to a manipulation check question that asked them to indicate the instructions they had received regarding evaluating the misstatement. The two choices were as follows: “as I normally would in practice” or “from the perspective of Joe Rogers, Purchasing Manager (i.e., by imagining myself in the place of the client- individual responsible for the misstatement).” Seventy-four of the 82 participants who completed the study (90.2%) correctly identified the instructions they had received. However, recalling the instructions received does not verify that participants actively considered the manager’s perspective during their evaluations. Thus, a more precise way of determining whether the perspective taking manipulation was successful is by using the measure of PT Engagement, which indicates whether participants actually considered, by their own admission, the manager’s perspective. I find that of the 42 participants who received perspective taking instructions, 19 actively engaged in perspective taking (i.e., were coded as High in PT Engagement) (45.2%). 15 Of the participants who did not receive perspective taking instructions, 23 (57.5%) spontaneously considered the perspective of the manager without being prompted.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Advocates of the disability community are not alone in their concern about the potential negative effects of NIPT on the reproductive trends of the population. Many worry there could be unintended consequences. One such concern is that the risk-free and simple process of NIPT will lead to the routinization of the test. In other words, NIPT may become a standard test that most women uptake simply because other women uptake and thus it seems “normal”. While this might increase efficiency and improve uptake, routinization could potentially undermine the decision-making process (Deans & Newson, 2011). Others feel alarmed by the reproductive power NIPT offers and wonder if in the future, a fetus might have to meet certain standards of desirable traits to qualify for birth. One ethicist suggested that potentially “every pregnancy becomes a ‘tentative pregnancy’ pending the results of prenatal screening” (Benn & Chapman, 2010, p. 131).
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Figure 2.2 The effects of porosity on thermal conductivity in uranium carbide.. Figure 2.3 The effects of oxygen impurity in uranium carbide.2[r]

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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Characterization of the developmental alloys was carried using SEM, EDS, TEM, and XRD analysis in order to evaluate grain size, dislocation microstructure, matrix microstructure and composition, and nanoparticle size, dispersion, and composition. The presented data only reflects particles observed in the images collected through the analysis techniques utilized; this only represents a very small sample of the microstructure and nanoparticle dispersion in the consolidated alloy. The resolution of SEM limits observations to particles of 10nm or larger and scanning electron microscopy only reveals the particle dispersion on the surface of the alloy; particles fully obscured within the alloy matrix are not properly represented as they are not observed or counted at all and particles partially obscured result in inaccurate calculated area estimates. A combination of SEM, EDS, TEM (EFTEM), XRD, and atom probe analyses would be necessary to form a comprehensive imaging record of as fabricated and irradiated microstructure, nanoparticle size, dispersion, and composition for 18CrODS and 9Cr ODS.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Specifically, I argue that an actor who anticipates the active consumption of a public good will contribute significantly more to its provision than an actor who anticipates [r]

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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

In Chapter 3, I have quantified the effect of three environmentally common anthropogenic antibiotics and their mixtures upon two species of common eukaryotic marine benthic primary pro[r]

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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Biotechnology, Inc., Santa Cruz, CA), according to the protocol of the manufacturer. Detailed method is described elsewhere (Xing et al., 2012). Briefly, 5 µm thick paraffin sections were prepared using (Leica RM2030, rotary microtome) and stored at room temperature until further staining. Using three changes of xylene and five chances of alcohol at varying concentration, sections were deparaffinized. Immunohistochemistry involved the use of microwave based antigen retrieval process for 30 minute in citrate buffer. Sections were blocked using 5% serum at 20 degree for 20 minutes followed by incubation with primary antibody (1/25 dilution) for overnight at 4 degree and corresponding secondary antibody was used. Cardiomyocytes were stained with rabbit anti-tropomyosin I(ab55915, Abcam Inc, Cambridge, MA) and nuclei were stained with DAPI. Images were acquired by observing slides under the fluorescence microscope (Nikon Eclipse E600; Nickon In, Melville, NY) at 400 × magnification. By using Qcapture software (MAG Corp., Pleasanton, CA), twenty fields of each section were randomly photographed and quantification was done using Image-Pro Plus software (Media Cybernetics, Inc., Bethesda, MD). Relative staining area was quantified and represented as integrated optical density (IOD) with respect to the area measured.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

are challenged to combine dynamic covalent and non-covalent interactions in complex mixtures to yield functional self-assembled materials through both spontaneous and assisted assembly. Such controlled self-assembly will have practical applications over a larger range of fields from medicine to electronics. For example, organic based semiconductors have promising applications in electronic and optoelectronic devices but are not nearly as developed as their inorganic counterparts. 191 Basic issues of how structure, both molecular and supramolecular architectures, influence electronic and optical properties are still under exploration. The goal of fabricating useful commercial electronics, batteries, and light harvesting devices will require not only control of assembled structures but also regulation of their ordering and registration within heterogeneous solids and interfaces. This means that there is much work ahead for the supramolecular chemist.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

female students enrolled in single gender classes had higher mean math and reading. scores compared to the females enrolled in single gender classes[r]

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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

The Theory of Planned Behavior (TPB) assumes that behavioral intention is the most important determinant of a given behavior (Ajzen, 1985; Ajzen, 1991). According to TPB, a person’s attitude towards a behavior (attitude toward behavior) and whether individuals who are important to the person approve or disapprove of the behavior (subjective norm) are the primary determinants of behavioral intentions (Ajzen, 1985; Ajzen, 1991). In this study, the focus groups assessed African American and White 18- 19 year old males’ intention to use condoms and contraception by inquiring about their thoughts and attitudes towards pregnancy at this point in their lives. Many focus group participants acknowledged their role and said that they could do their part in preventing a pregnancy by using condoms. These findings aligned with constructs from the TPB (Ajzen, 1985; Ajzen, 1991). Perceived behavioral control was also significant in the study (Ajzen, 1985; Ajzen, 1991). Specifically, African American and White 18-19 year old males were asked about their role in the use of contraception with sexual partners, which helped to clarify their perceived control related to engaging in sexual risk behaviors.
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