Impact Analysis and Mitigation of Voltage Regulation Issues in PV Rich Low Voltage Residential Distribution Networks

Modern distribution networks are undergoing major changes with the increased uptake of rooftop photovoltaic (PV) units in low voltage (LV) residential distribution networks. These renewable based distributed energy resources (DERs) impose adverse effects which can propagate from LV to medium voltage (MV) and high voltage (HV) levels. Some of the major areas of concern to network operators include reverse power flow, voltage unbalance, voltage rise, increased harmonics, increased potential of islanding, and component and line overloading. These issues create both an operational mitigation requirement and a need for Distribution Network Service Providers (DNSPs) to adjust LV network design procedures. In Australia DNSPs are bound by strict regulation to provide supply to customers complying with several power quality standards. Australian Standard AS 61000.3.100 requires the voltage at the consumer point of supply to be within +10%, -6% of the 230 V nominal for single phase LV customers. Since residential peak load is typically observed during evening time and power generated from PV during daytime, rooftop PV does little to reduce peak demand. Increased numbers of rooftop PV systems in future LV feeders, combined with increased demand, means DNSPs need to invest in infrastructure to alleviate issues related to overgeneration or overloading and voltage regulation. Traditionally, voltage regulation devices such as on-load tap changers (OLTCs), regulators and capacitor banks have been sufficient to regulate voltage within mandated limits. Bidirectional power flow that arises as a result of DER in LV limits the ability of these devices, as LV voltage issues cannot be detected or do not propagate further up the network. Compared to HV/MV networks, residential LV networks experience more variable loads, have inherent unbalance due to the overhead 4-wire structure, and lack visibility with respect to operational states. This thesis aims to contribute new knowledge and understanding to the field of power distribution network voltage regulation. This includes investigation and analysis of different approaches to voltage regulation in power distribution networks in the literature, and to propose new methods and improvements to existing methods. Specifically, this thesis aims to highlight the shortcomings of the current voltage regulation techniques available to DNSPs in LV feeder. The case studies to be provided in this thesis presents 24 h time series simulation to investigate the performance with varying load and PV generation

A Data Driven Approach to Quantify the Impact of Crashes

The growth of data has begun to transform the transportation research and policy, and open a new window for analyzing the impact of crashes. Currently for the crash impact analysis, researchers tend to rely on reported incident duration, which may not always be accurate. Further, impact of the crashes could linger a much longer time at upstream, even if the records are correct for the crash spot and it is a challenge to quantify the impact of a crash from the complex dynamics of the recurrent and non-recurrent congested condition. Therefore, a difference-in-speed approach is developed in this research to estimate the true crash impact duration using stationary sensor data and incident logs. The proposed method used the Kalman filter algorithm to establish traveler’s anticipated travel speed under incident-free condition and then employ the difference-in-speed approach to quantify the temporal and spatial extent of the crash. Moreover, potential applications such as statistical models for predicting the impact duration and total delay were developed in this research. Later, an analysis on distribution of travel rate was performed to describe and numerically show to what extent crashes influenced travel rates compared with the normal conditions at different periods of the day and by the crash types. This study can help to shape incident management policies for different types of crashes at different periods and illustrates the usages of data to improve the understanding of crashes, their impact, and their distribution in a spatial-temporal domain

An investigation of macroamphiphile composition and biosynthesis in representative Actinomycete bacteria

Studies of the distribution of macroamphiphiles in Gram-positive bacteria are interesting in relation to understanding their functions and are of chemotaxonomic value at the supergeneric level. Previous studies have revealed the distribution of lipoteichoic acid (LTA) in the low G+C phylum Firmicutes and typically parallel that of the teichoic acid as a secondary cell wall polymer (SCWP). The present study had focused on the distribution of macroamphiphiles in the high G+C phylum Actinobacteria, where most previous studies have revealed liopglycans as the macroamphiphiles in various different lineages of the phylum. The present study has, for the first time, investigated macromaphiphiles in a thermophilic Actinobacterium, Thermobifida fusca. The study detected the presence of LTA, with detailed structural analysis. This confirms the compatibility of these macromolecules with membrane adaptation at higher temperatures. A second thermophilic Actinobacteria, Rubrobacter xylanophilus (which had moved recently to the most distant lineage of the phylum) was found to lack of typical macroamphiphiles. The present study also detected a novel LAM-like molecule in Kineococcus radiotolerans suggesting a close relationship between the distribution of LAM or LAM-like molecules and that of the SCWP, arabinogalactan (AG). The study also identified the presence both LTA and lipoglycan in two representatives of the genus Streptomyces (Streptomyces coelicolor and Streptomyces sp. DSM40537). This allows a re-evaluation of the hypothesis (Fischer, 1994) that a single type of major macroamphiphile is normally present in a single organism. Extending these findings, comparative genomic analyses suggest that the LTA biosynthesis pathway in Actinobacteria might be different from that in the Firmicutes. The alanine substitution pathway for LTA and teichoic acids (TA) was also found to be absent from the phylum Actinobacteria. Moreover, the comparative genomic analyses for Kineoccus radiotolerans were consistent with the practical results for this organism, illustrating the potential of predicting macroamphiphile composition utilizing genome databases. The study had also confirmed that the distribution of macroamphiphiles and SCWPs has importance chemotaxonomic value especially at the supra-generic level; it can be hypothesised from the study that: LTA containing Actinobacteria contain TA as a SCWP, whilst lipoglycan containing Actinobacteria generally contains other SCWPs, such as AG rather than TA

Develop a Highway Inventory Data Quality Control Scheme (PL-26)

Since passage of the Moving Ahead for Progress in the 21st Century (MAP-21), transportation agencies have become increasingly reliant on data for planning and programming, asset management, and performance tracking. An efficient asset inventory database with accurate data is critical for states to comply with MAP-21 (and now FAST Act) requirements. The Kentucky Transportation Cabinet’s (KYTC) Division of Planning maintains the Highway Information System (HIS), which is a primary source of this information for transportation professionals at the Cabinet (KYTC). Because highway system is continually changing, it is a challenging task to keep the information in the HIS up to date. Further, the level of accuracy and precision of the initial data collection activities vary among the agencies tasked with data collection. This study developed a quality check program of the HIS to ensure key items in the database are accurate. KYTC identified a list of priority data items to include in this assessment. They were: (1) Number and width of through lanes; (2) Type and width of medians; (3) Presence and width of auxiliary lanes (e.g., truck climbing, turning, two-way left turn); and (4) Type and width of shoulders. For this study, Kentucky Transportation Center (KTC) researchers developed a process to systematically sample highway segments and generate data collection points. These points were located on Google Earth and Google Street View so that those programs ’ native tools could be used to measure the relevant attributes.Researchers then compared the HI S records and observed data to identify possible errors. This study’s analysis verified that the vast majority of the sampled segments have accurate entries in the HIS database. For Through Lane and Shoulder asset types, inconsistencies between the observed and archived data were mostly on roads in small urban areas and rural minor arterials or lower functional groups.Since they account for about 86% of the total mileages in Kentucky, additional sampling of roads in these groups is recommended. Median width was identified as another item that warrants further review. The Auxiliary Lane asset type appears to have the least inconsistency between the observed and archived data, according to random samples

HEAVY METAL TOXICITY IN FISHES OF POLLUTED LAKES OF DHAKA CITYAND ITS IMPACTS ON HUMAN HEALTH

The City of Dhaka is not built up plan wise from the beginning yet till date. The land uses are not following the urbanization rules correctly. Due to the laggings of proper water and air flow and basic treatment of household and industrial utilizing water, some of the major health issues are concerned. This research works is on the focus of heavy metal contamination in fishes of two major lakes in Dhaka city called Dhanmondi Lake and Gulshan Lake. The research is focusing mainly the study on Cr, Cd and Pb concentration in fishes along with other elements. Concentration of Cr is found in ranges of 3.45 μg/gm – 10.25 μg/gm, Cd is 2.17 μg/gm – 9.78 μg/gm and Pb is 1.132 – 7.102 μg/gm. The major element K and Ca with other trace elements are also projected. The data acquisition setup is calibrated using 2.2 MeV proton beam in the current ranges of 5nA to 15nA. The Van-de Graff Accelerator of Atomic Energy Centre, Dhaka has been used for sample irradiation. The IBA technique Proton Induced X-ray Emission (PIXE) has been applied using Si(Li) detector (SL30165) and other ORTEC nuclear electronics. The calibration and standardization of PIXE setup has been done using X-ray source, and IAEA standard CuSx (thin), Soil-7 (thick)

An investigation of macroamphiphile composition and biosynthesis in representative Actinomycete bacteria

Studies of the distribution of macroamphiphiles in Gram-positive bacteria are interesting in relation to understanding their functions and are of chemotaxonomic value at the supergeneric level. Previous studies have revealed the distribution of lipoteichoic acid (LTA) in the low G+C phylum Firmicutes and typically parallel that of the teichoic acid as a secondary cell wall polymer (SCWP). The present study had focused on the distribution of macroamphiphiles in the high G+C phylum Actinobacteria, where most previous studies have revealed liopglycans as the macroamphiphiles in various different lineages of the phylum. The present study has, for the first time, investigated macromaphiphiles in a thermophilic Actinobacterium, Thermobifida fusca. The study detected the presence of LTA, with detailed structural analysis. This confirms the compatibility of these macromolecules with membrane adaptation at higher temperatures. A second thermophilic Actinobacteria, Rubrobacter xylanophilus (which had moved recently to the most distant lineage of the phylum) was found to lack of typical macroamphiphiles. The present study also detected a novel LAM-like molecule in Kineococcus radiotolerans suggesting a close relationship between the distribution of LAM or LAM-like molecules and that of the SCWP, arabinogalactan (AG). The study also identified the presence both LTA and lipoglycan in two representatives of the genus Streptomyces (Streptomyces coelicolor and Streptomyces sp. DSM40537). This allows a re-evaluation of the hypothesis (Fischer, 1994) that a single type of major macroamphiphile is normally present in a single organism. Extending these findings, comparative genomic analyses suggest that the LTA biosynthesis pathway in Actinobacteria might be different from that in the Firmicutes. The alanine substitution pathway for LTA and teichoic acids (TA) was also found to be absent from the phylum Actinobacteria. Moreover, the comparative genomic analyses for Kineoccus radiotolerans were consistent with the practical results for this organism, illustrating the potential of predicting macroamphiphile composition utilizing genome databases. The study had also confirmed that the distribution of macroamphiphiles and SCWPs has importance chemotaxonomic value especially at the supra-generic level; it can be hypothesised from the study that: LTA containing Actinobacteria contain TA as a SCWP, whilst lipoglycan containing Actinobacteria generally contains other SCWPs, such as AG rather than TA.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Bangladesh’s Trade Partners and the J-Curve: An Asymmetry Analysis

Separating currency appreciations from depreciations and using nonlinear models in recent literature have improved discovering significant link between the trade balance and the exchange rate. We add to this growing literature by considering the experience of Bangladesh with 11 trading partners. When a linear model was used, support for the J-curve effect was present only with one small partner. However, when a nonlinear model was used, support increased to three countries including the largest partner, the U.S. which accounts for more than 12% of Bangladesh’s trade. Furthermore, the nonlinear models supported short-run asymmetry adjustment as well as short-run asymmetry effects of exchange rate changes in most cases. However, long-run asymmetric effects were limited to a few

Level of Awareness about HIV/AIDS among Ever Married Women in Bangladesh

Abstract Ever married women are more vulnerable group to sexually transmitted diseases (STDs), HIV/AIDS infection, and unplanned pregnancies. The aims of this study are to assess the level of awareness among ever married women on HIV/AIDS and to determine the affecting factors influenced knowledge and awareness about HIV/AIDS regarding its prevention and control. The data on 10,996 ever married women in their reproductive span (15-49 years) was taken from the Bangladesh Demographic and Health Survey (BDHS), 2007. The statistical tools, Chi square (χ 2 ) test and binary logistic regression analysis have been performed to analyse the data. Both bivariate and multivariate analyses identified that respondent's education, husband's education, husband's occupation, age at marriage, watching TV, electricity in the household, marital status, and residence are found to have statistically significant effects with HIV/AIDS awareness (p<0.01). Marriage in the older age (>18 years), education, and mass media campaigns are strongly suggested for increasing knowledge and awareness to be controlled the spread of HIV/AIDS as well as STDs among ever married women in Bangladesh