Comparative study of various controllers applied to a three phases parallel multi-cell buck converter

Un programme de recherches a été entrepris pour comparer vingt-deux nouveaux cépages et trois anciennes variétés sur quatre zones viticoles de la Haute-Moselle. La première phase de ce programme s'est étendue sur cinq ans (1975-1980). L'examen de vingt caractéristiques portant sur les raisins, les moûts et les tests sensoriels des vins obtenus montre Ia supériorité des nouveaux cépages sur le cépage témoin « Elbling blanc ».Sur les vingt-deux cépages testés, au cours de la première phase des recherches, les résultats obtenus ont permis aux auteurs de sélectionner pour la deuxième phase de l'étude les huit cépages suivants : Faberrebe, Kerner, Gutenborner, Ortega, Reichensteiner, Forta, Rabaner et Regner.+++A comparative study has been made between twenty-two new and three traditional varieties. They are located in four different sites in the Upper-Moselle wine-growing area. The date presented is based on a five-year (1975-1980) programme, which is one of three phases. Twenty characteristics has been taken into account. Experiments in vinification and sensoric wine tests showed great improvements when compared with the variety « white Elbling » which has been taken as control.After having got the results of the first part of the study, we selected to continue the experiments with eight varieties instead of twenty-two, namely : Faberrebe, Kerner, Gutenborner, Ortega, Reichensteiner, Forts, Rabaner and Regner.

Download Full-text

COMPARATIVE STUDY AND IMPLEMENTATION OF INCREMENTAL CONDUCTANCE METHOD AND PERTURB AND OBSERVE METHOD WITH BUCK CONVERTER BY USING ARDUINO

International Journal of Research in Engineering and Technology ◽

10.15623/ijret.2014.0301079 ◽

2014 ◽

Vol 03 (01) ◽

pp. 461-469 ◽

Cited By ~ 2

Author(s):

Roshan Kini .

Keyword(s):

Comparative Study ◽

Buck Converter ◽

Incremental Conductance ◽

Perturb And Observe ◽

Conductance Method

Download Full-text

Constructivist Approach for E-Learning Effectiveness in African Higher Education Contexts

Asian Journal of Research in Computer Science ◽

10.9734/ajrcos/2021/v8i230197 ◽

2021 ◽

pp. 29-41

Author(s):

Mohamed Elfateeh Alobeed A Ismail ◽

T. Gnana Sambanthan

Keyword(s):

Higher Education ◽

Comparative Study ◽

Survey Methods ◽

Self Regulation ◽

Learning System ◽

Learner Characteristics ◽

African Countries ◽

African Higher Education ◽

E Learning ◽

Three Phases

There is a spurt in online learning worldwide, particularly in Asian and African countries, after the COVID-19 pandemic. Outcomes Based Education (OBE), the new paradigm in Africa, India and elsewhere in the world promotes e-Learning as part of its Lifelong learning attribute. Design of such e-Learning system should incorporate features of autonomous learner’s characteristics (like African higher education students) for their preparedness and progression phases of e-Learning. This is due to the fact that the learning environment and learner characteristics, may differ from place to place and cultures. As per literature, principles of constructivist theory have been successfully adapted for e-Learning. Meta-cognition is a new addition to the OBE paradigm besides cognitive, affective and psychomotor domains, that plays important role in e-Learning. This paper attempts to construct metrics for meta-cognition using constructivist’s learning parameters, for analyzing three phases of e-Learning. Literatures are limited on meta-cognitive studies of e-Learner characteristics. The novelty of the paper is the adaptation of certain principles of ecological system on meta-cognition with literature support. Inductive research with appropriate methodology is applied for studying the effectiveness of e-Learning. Ecological factors in the meta-cognition aspects of the constructivist’s theory have been considered. Two parts are treated by the paper: i. Comparative study between Indian and African scenario; ii. Detailed study of selective African countries on the preparedness and progression phases of e-Learning. Survey methods have been chosen for obtaining feedbacks on scientifically designed questionnaire. Three hypotheses on the meta-cognitive aspects of self-regulation and a null hypothesis for the comparative study, have been constructed. Observations on the three phases of e-Learning have been documented and inferences drawn. Conclusions made out our research study along with the results presented will be of immense use to e-Learning system designers, particularly for the African scenario.

Download Full-text

Paṭhamasambodhi in Nine Languages: Their Relation and Evolution

MANUSYA ◽

10.1163/26659077-00601002 ◽

2003 ◽

Vol 6 (1) ◽

pp. 11-34 ◽

Cited By ~ 1

Author(s):

Anant Laulertvorakul

Keyword(s):

Comparative Study ◽

Southeast Asia ◽

Original Version ◽

Second Phase ◽

The Comparative Study ◽

Three Phases

Paṭhamasambodhi is widespread in at least 5 countries in Southeast Asia. Hundreds of manuscripts and not less than 10 versions have been discovered. They are composed in 4 languages: Pāli, Mon, Cambodian and Tai, including Tai vernaculars: Siamese Thai, Northern Thai Northeastern Thai, Lao, Tai Lue, and Tai Khoeun. The styles of composition dramatically vary between detailed enumeration and concision, prose and verse, translation in the style of nissaya and non-nissaya, single language and dual languages—Pāli and another language. The comparative study of the different versions, with emphasis on their content, reveals their relation and the evolution of Paṭhamasambodhi. The Pāli version found in the Lanna region is the oldest complete version. It is probably the original version, which not only is rendered to Tai Lue, Tai Khoeun, Lao and Northern Thai, but evolved over centuries to become the three newer Pali recensions which later were rendered to northeastern Thai, Mon and Siamese Thai. The latter version was finally rendered to Cambodian. The content of Paṭhamasambodhi was gradually enhanced in three phases with different genres: 1) the legend of the Siddhattha Bodhisatta in the Pali of the Lanna region, the Northern Thai the Lao, the Tai Khoeun and the Tai Lue versions; 2) the legend of the Gotama Buddha in the two late Pāli versions as well as the Mon and the northeastern Thai versions; and 3) the legend of the Gotama Buddha's sāsana or teaching in both Pāli and Siamese Thai versions by His Supreme Patriarch Prince Paramanujitjinorot and the Cambodian version. The Northern Thai version is the transition link between the first and the second phase. The result of this study also provides the genesis of Paṭhamasambodhi.

Download Full-text

A Comparative Study on the Switching Performance of GaN and Si Power Devices for Bipolar Complementary Modulated Converter Legs

Energies ◽

10.3390/en12061146 ◽

2019 ◽

Vol 12 (6) ◽

pp. 1146 ◽

Cited By ~ 4

Author(s):

Baochao Wang ◽

Shili Dong ◽

Shanlin Jiang ◽

Chun He ◽

Jianhui Hu ◽

...

Keyword(s):

Comparative Study ◽

Dead Time ◽

High Electron Mobility Transistors ◽

Buck Converter ◽

Switching Frequency ◽

High Electron ◽

Switching Loss ◽

Gan Hemt ◽

Switching Losses ◽

High Switching Frequency

The commercial mature gallium nitride high electron mobility transistors (GaN HEMT) technology has drawn much attention for its great potential in industrial power electronic applications. GaN HEMT is known for low on-state resistance, high withstand voltage, and high switching frequency. This paper presents comparative experimental evaluations of GaN HEMT and conventional Si insulated gate bipolar transistors (Si IGBTs) of similar power rating. The comparative study is carried out on both the element and converter level. Firstly, on the discrete element level, the steady and dynamic characteristics of GaN HEMT are compared with Si-IGBT, including forward and reverse conducting character, and switching time. Then, the elemental switching losses are analyzed based on measured data. Finally, on a complementary buck converter level, the overall efficiency and EMI-related common-mode currents are compared. For the tested conditions, it is found that the GaN HEMT switching loss is much less than for the same power class IGBT. However, it is worth noting that special attention should be paid to reverse conduction losses in the PWM dead time (or dead band) of complementary-modulated converter legs. When migrating from IGBT to GaN, choosing a dead-time and negative gate drive voltage in conventional IGBT manner can make GaN reverse conducting losses high. It is suggested to use 0 V turn-off gate voltage and minimize the GaN dead time in order to make full use of the GaN advantages.

Download Full-text