Degradation modeling and degradation-aware control of power electronic systems

The power electronics market is valued at $23.25 billion in 2019 and is projected to reach$ 36.64 billion by 2027. Power electronic systems (PES) have been extensively used in a wide range of critical applications, including automotive, renewable energy, industrial variable-frequency drive, etc. Thus, the PESs\u27 reliability and robustness are immensely important for the smooth operation of mission-critical applications. Power semiconductor switches are one of the most vulnerable components in the PES. The vulnerability of these switches impacts the reliability and robustness of the PES. Thus, switch-health monitoring and prognosis are critical for avoiding unexpected shutdowns and preventing catastrophic failures. The importance of the prognosis study increases dramatically with the growing popularity of the next-generation power semiconductor switches, wide bandgap switches. These switches show immense promise in the high-power high-frequency operations due to their higher breakdown voltage and lower switch loss. But their wide adaptation is limited by the inadequate reliability study. A thorough prognosis study comprising switch degradation modeling, remaining useful life (RUL) estimation, and degradation-aware controller development, is important to enhance the PESs\u27 robustness, especially with wide bandgap switches. In this dissertation, three studies are conducted to achieve these objectives- 1) Insulated Gate Bipolar Transistor (IGBT) degradation modeling and RUL estimation, 2) cascode Gallium Nitride (GaN) Field-Effect Transistor (FET) degradation modeling and RUL estimation, and 3) Degradation-aware controller design for a PES, solid-state transformer (SST). The first two studies have addressed the significant variation in RUL estimation and proposed degradation identification methods for IGBT and cascode GaN FET. In the third study, a system-level integration of the switch degradation model is implemented in the SST. The insight into the switch\u27s degradation pattern from the first two studies is integrated into developing a degradation-aware controller for the SST. State-of-the-art controllers do not consider the switch degradation that results in premature system failure. The proposed low-complexity degradation-aware and adaptive SST controller ensures optimal degradation-aware power transfer and robust operation over the lifetime

Paper Session II-C - An Inventory of Florida\u27s Space-Related Academic Support Capabilities

The University of Central Florida, in cooperation with the developing an inventory of Florida’s university and Spaceport Florida Authority, is college-level space research, education/training capabilities and programs. Upon completion in early 1996, the inventory will be useful in the following ways: 1) space-related companies and agencies will use the inventory to select academic capabilities to support their programs; 2) the inventory will be distributed among the state’s academic institutions to enable teaming for research projects and grants; 3) the inventory will allow the academic community and Florida’s university system administrators to better understand their strengths and weaknesses in the space field; 4) and the inventory will be useful to local and state economic development organizations in attracting new space-related business to Florida

Comparative Meat Production Performance Evaluation of Buffalo with Cattle at Different Ages

An inquisitive on-station feeding trial was carried out to identify the dexterous species and age for beef production with same plane of nutrition. A 2×3 (2 species × 3 ages) factorial experiment was settled for a period of 105 days with eighteen native buffalo and 18 BCB-1 (BLRI Cattle Breed-1) bulls of three age groups (18 months, 24 months and 30 months) and distributed them randomly in six treatment groups having an equal number (6) of animals in each. Intake of nutrients i.e.: DM, CP of buffalo bulls was significantly (p<0.001) higher than BCB-1 bulls in all the cases. The buffalo bulls had significantly higher digestibility of DM (68.0%, p<0.001), OM (67.9%, p<0.001), CP (66.3%, p<0.05), ADF (59.8%, p<0.001) or NDF (59.6%, p<0.001) than cattle (63.0%, 62.7%, 63.6%, 52.4% & 49.6%, respectively). But, the digestibility of DM, OM, CP, ADF or NDF was not affected significantly (p>0.05) by the age of the bulls with any cases. Buffalo bulls gained body weight more rapidly (p<0.001); 1.11 & 0.88 kg/day, respectively and showed a better FCR (p>0.05; 6.72 & 6.86, respectively) than cattle with low feed cost of per kg gain (US 1.62 & US 1.69, respectively). ADG (p<0.01), FCR (p<0.05) and estimated feed cost (p<0.05) affected significantly and increased linearly by the age of bulls, where 18 months bulls of buffalo and BCB-1 performed best. In an aggregation, it revealed that, buffalo performed better than BCB-1 cattle and 18 months age of both species was more responsive for profitable meat production

Mitigation of Salt Stress by Foliar Application of Jasmonic Acid in Wheat

 Two individual experiments were conducted to investigate the effects of salinity from germination to seedling stage and exogenous application of methyl jasmonate (MeJA) to mitigate the adverse effects of salinity in wheat. The results of laboratory experiment showed that salt stress reduced germination percent and seedling fresh weight of wheat. The BARI Gom 25 exhibited better performance under saline environment upto 12 dSm-1. The field experimental results showed that plant height, leaf number, tiller number, fresh and dry weight per plant, spike length, grain number and weight per spike and yield of wheat were reduced with increased levels of salinity generally at 8 dS m-1. Exogenous application of MeJA significantly mitigated the adverse effects of salinity by improving morpho-physiological, yield contributing and yield characters of wheat. The interaction between different levels of salinity and MeJA improved the morpho-physiological, yield contributing characters and yield of wheat. The yield of wheat increased with 10 µM MeJA from 2.22 to 2.77 t ha-1, 1.63 to 2.01 t ha-1, 1.15 to 1.39 t ha-1 at 0 dS m-1, 4 dS m-1, 8 dS m-1 salinity, respectively and suggested that MeJA mitigate the adverse effects of salt stress in wheat. 

Ethics in public relations and responsible advocacy theory

Ethics in public relations plays a vital role in human communication. It brings the credibility to organizations. It helps to establish faithful relationship between organizations and the public. Excellence in public relations can be achieved by ethical practices. Public relations organizations should follow code of ethics to provide reliable services to the target audience. Organizations need to ensure that the codes of ethics are practically implemented for the betterment of all the stakeholders. The responsible advocacy theory is one of the latest theories of ethics in public relations. It focuses on the responsibilities of public relations practitioners. It is based on three major principles of public relations ethics: the comparison of harms and benefits, respect of persons, and distributive justice. It encourages to avoid all harmful contents, guarantee the public interest, safeguard the human dignity and maintain justice in communication. This article highlights on the basic concepts of ethics in public relations, codes of ethics in different public relations organizations and key points of responsible advocacy theory

Seasonal Weather Impacts on Biomass Production of Moringa oleifera at Different Fertilizer Doses

A year round agronomical trial was conducted on station (Bangladesh Livestock Research Institute) to investigate the impact of seasonal variations on biomass production of Moringa oleifera at different fertilizer doses in Bangladesh. A 6×3 factorial arrangement in a completely randomized design (CRD) was applied on 20m×12m =240 m2 size plot, established in 2006 with a plant density of 13,500/hectare, was equally divided into 18 sub-plots and randomly grouped into three; 6 plots was treated as control, 6 plots was treated as medium with medium doses of fertilizer and rest 6 was treated as high fertilizer dose with the ratio of N.P.K was 90:30:15 and 160:60:40 kg/ha, respectively. The obtained result revealed that, the summer was the best season and autumn, monsoon and spring was also favorable for getting maximum yield of Moringa oleifera with ambient temperature ranges 27-320C and fertilization dose N:P:K= 90:30:15 is suitable for optimum moringa production and chemical composition of moringa varied with season and slightly with fertilization

Method of doping silicon, metal doped silicon, method of making solar cells, and solar cells

A low temperature process for forming a metal doped silicon layer in which a silicon layer is deposited onto a substrate at low temperatures, with a metal doping layer then deposited upon the silicon layer is described. This structure is then annealed at low temperatures to form a metal doped semiconductor having greater than about 1x10^20 dopant atoms per cubic cm of silicon

Corporate Governance Mechanisms and Capital Structure Decision of Textile Companies in Bangladesh

Purpose: The purpose of this study is to examine the impact of corporate governance mechanisms on capital structure decisions of Textile Companies in Bangladesh. In particular, the paper examines the degree to which internal corporate governance mechanisms and an external corporate governance mechanism affect Bangladeshi textile firms’ capital structure. Methodology of the Study: The paper uses a multiple regression analysis to examine the effect of corporate governance and capital structure for a sample of 10 Bangladeshi textile firms listed in DSE during period from 2011 to 2017.Board size, Board composition, Board meetings & Board ownership were used as corporate governance variables and Return on Assets (ROA) also used as control variable and debt ratio used as the measure of capital structure. This study also used different statistical tools like descriptive statistics, Pearson correlation and multiple regressions. Findings: The findings indicate that the relationship of Debt Ratio with Board Size & Board Composition is positive and highly significant, a less significant or moderate positive relationship between Debt Ratio & Board Ownership, insignificant and negative relationship between Debt Ratio & Board Meetings and the Debt Ratio is negatively related to Return on Assets that is significant.CG mechanisms (Board Size & Board Ownership) are significantly and positively impact on firms Capital Structure/ Debt Ratio (DR) and (Board Composition & Board Meetings) are also positively impact on firms Capital Structure but that is statistically insignificant and Return on Assets is highly significant & negatively impact on firms Capital Structure/ Debt Ratio (DR) of Listed Textile Companies in Bangladesh. [Keywords: Corporate Governance (CG), Capital Structure (CS), Debt Ratio (DR)] DOI: 10.7176/JESD/10-20-02 Publication date:October 31st 201