PFC Topologies for AC to DC Converters in DC Micro-Grid

With increasing dominance of renewable energy resources and DC household appliances, the novelty of DC micro grid is attracting significant attention. The key interface between the main supply grid and DC micro grid is AC to DC converter. The conventional AC to DC converter with large output capacitor introduces undesirable power quality problems in the main supply current. It reduces system efficiency due to low power factor and high harmonic distortion. Power Factor Correction (PFC) circuits are used to make supply currents sinusoidal and in-phase with supply voltages. This paper presents different PFC topologies for single phase AC to DC converters which are analyzed for power factor (PF), total harmonic distortion (THD) and system efficiency by varying output power. Two-quadrant shunt active filter topology attains a power factor of 0.999, 3.03% THD and 98% system efficiency. Output voltage regulation of the presented active PFC topologies is simulated by applying a step load. Two-quadrant shunt active filter achieves better output voltage regulation compared to other topologies and can be used as grid interface

Cost Effective Bidirectional Power Transactions for Queueing Energy Requests in Smart Micro-Grids

This paper investigates real time problem of cost efficient energy distribution within smart micro-grids (SMG). The aggregator announces a day-ahead price of electricity, and is most often not fully aware of on spot availability of renewable resources. Sometimes, users also encounter estimation errors in their day-ahead energy procurement. In both situations an extra cost is incurred to aggregator or the users to fulfill their needs. This cost could be minimized by intelligently balancing the real time renewable generations with users load demands. The problem is more complex when there are a number of users communicating with each other and with the aggregator at the same time through a Digital Energy Management System (DEMS) for their demand requirements. It is very challenging for DEMS to ensure comfort level for its consumers while providing low cost electricity. Hence, we establish an optimization problem of curtailing the time average cost of electricity, under certain bounds of consumers satisfactions. We introduce load scheduling and energy transaction (LSET) control policy based on Lyapunov optimization theory to develop our proposed solution

Determine the Association Between Nurses Self-Concept and Clinical Performance Among Nursing Students

Self-concept in clinical performance had an important role in applying competencies and self-concept in clinical performance influenced to quality care of nursing students. Self-concept is the key point for patient care by the student nurses which is established with continues education, gaining knowledge, learning skills and making attitudes. The purpose of the study is to determine the association between nurses self concept and clinical performance among nursing students. Descriptive cross sectional study was conducted in the school of nursing at Jinnah hospital Lahore. The study data were collected using a questionnaire which consisted of Nursing Self Concept Questionnaire (NSCQ) and Six Dimension Scale of nurse performance 6-(DSNP). Pearson Correlation test was used to explore the relationship of variables. The results of the study show that clinical performance and professional self-concept are related. These findings can be helpful to teachers, authorities at nursing colleges, and nursing managers. Keywords: Professional Self concept; clinical performance; nursing students. DOI: 10.7176/JHMN/61-09 Publication date: April 30th 201

Key Performance Indicators for Sustainable Freight Transport and Scenario-based Impediments in Pakistan Freight Industry

Freight transport enables economic growth, market connectivity, and access to the global supply chain systems which contribute to the societal progress and inclusive development of a country. However, it may undermine the sustainable operations by incurring external costs, inefficiency, and economic losses due to non-reliability, poor services, and information systems. In this research study, the Key Performance Indicators (KPIs) for Sustainable Freight Transport Systems (SFTS) are discussed based on available literature review and standards of sustainability measurement in freight transport. Then, based on KPIs some of the scenario-based impediments are highlighted which hinder the performance of the freight transport in Pakistan for achieving sustainable development goals. The core impediments included are Strategic Determinants (SD), Information Systems (IS), Infrastructure Management Systems (IMS) and City Logistics (CL). The negative direct impacts of the key identified factors are also highlighted and linked with each scenario-based impediment. This research study would provide an opportunity for the stakeholders to get tangible idea for policy making and upgradation of the freight transport industry in the country. The highlighted implications will also be validated via expert surveys and Delphi-analysis in the future study.

ASSESSMENT OF NURSES’ PRACTICES REGARDING BED-BATH OF CRITICALLY ILL PATIENTS IN TERTIARY CARE HOSPITAL LAHORE

Introduction: Every day bed-bath are normally accommodated most basically sick patients to improve their cleanliness, advance solace and improve wellbeing results. Fundamentally sick patients are at more serious hazard for skin colonization and contamination with multidrug-resistance pathogenic organisms. Hence, it is imperative to furnish basically sick patient with powerful close to home cleanliness particularly bed-bath as poor cleanliness may expand the danger of contamination. Methodology: quantitative observational descriptive study design was used to assess the nurses’ practices regarding bed-bath of critically ill patients. In order to assess nurses practiced, data was collected through the standardized checklist regarding bed bath. The check consists of 51 items. Results: The findings of this study revealed that there is poor practices of nurses regarding bed bath of critically ill patients. Conclusion: This study has described an important basic nursing care that is bed-bath practice in critically ill patient. Although, bed-bath is a routine nursing procedure, critical care nurses in the current study had poor skills and practices regarding it. This study has implications for clinical practice and nursing research. Bed-bath is a routine nursing care; many nurses understand that bathing is just for cleaning. Therefore, Inservice training program should be conducted Key words: bed bath, practice, critical, patient. DOI: 10.7176/JHMN/74-08 Publication date:May 31st 202

Factors Affecting the Rate of Breast Cancer; Role of Heavy Metals

Breast cancer is caused by uncontrolled growth of breast cells. It is more common in women as compared tothat in men. The breast cancer may be interlinked with the drinking of alcohol, smoking, sex, hormonal therapy, obesity,family history and age. Various epidemiologic studies suggest the role of metals e.g., nickel (Ni), zinc (Zn), arsenic(As),selenium (Se)and cadmium (Cd)as potential risk factors in breast cancer. Humans are exposed to these metals bymeans of drinking water, food and air. The oxidative theory suspects that the complexes formed from these metals invivo, near the location of DNA, catalyze the redox reactions which results in oxidation of DNA. The metals like arsenic(As), chromium (Cr), aluminum (Al), cadmium (Cd) and chromium (Cr)which exist in trace amount are considered ascarcinogens for organisms by IARC (International Agency for Research on Cancer). The carcinogenicity of these metalsmainly depends upon their chemical structure and oxidation states

Evaluation of Bentonite Mixed Indigenous Clays for Development of Clay Liners

This study presents experimental investigation of indigenous clays mixed with Bentonite to assess their suitability in potential use as clay liners. Soil samples with 0, 4, 8, and 12% Bentonite content from three different sites in Peshawar region were tested for various geotechnical properties. Grain size distribution, specific gravity, Atterberg limits and free swell were found through laboratory tests using appropriate ASTM procedures. Maximum dry density and optimum moisture content were calculated using Atterberg limits in available relationships. Finally, one dimensional consolidation tests were conducted to find relevant parameters for calculating hydraulic conductivity. A decrease in specific gravity, increase in free swell, and in optimum moisture content, decline in maximum dry density and hydraulic conductivity was observed with increase in Bentonite content across all three soil samples. During free swell, the soil clusters become larger leading to formation of floccules resulting in the narrowing of inter-particle space and thus blocking of permeable paths. It is concluded that 8% Bentonite content by weight yields a suitable mixture for a clay liner that has hydraulic conductivity in the range of recommended limits