scholarly journals Analysis of the Increase of Transformer Power Losses due to the Operation of Unbalanced Nonlinier Loads

2018 ◽  
Vol 2 (2) ◽  
pp. 38
Author(s):  
I Wayan Rinas ◽  
I Made Suartika ◽  
Anak Agung Maharta Pemayun

Non-linear loads are the source of harmonic current for electric utilities. The high level of harmonics greatly affects the increase of losses of electrical power (losses). The quality of electric power is determined by the parameters of power losses that occur in the transformer due to harmonic distortion. In this research will be analyzed THD from result of measurement and simulation in accordance with IEEE 519-2014 standard, power loss analysis on transformer before and after. Harmonics, the impact is increased due to unbalanced linear currents.

Author(s):  
Eva Magdalena Silalahi ◽  
Bambang Widodo ◽  
Robinson Purba

Currently, people are increasingly using energy saving lamp (LHE) and LED because of their energy saving and low power consumption. But the use of LHE and LED in large quantities can reduce the quality of electric power. This is because LHE and LED are classified as non-linear loads which are a source of harmonic distortion for low-voltage power lines. Harmonic distortion occurs due to non-linear load currents that experience distortion or defects. Based on this, this study aims to investigate the effect of the collective use of LHE and LEDs on the quality of electrical power, such as: harmonic levels, power factor, and the resulting harmonic current and voltage waveforms. The results of this study indicate that the simultaneous use of LHE and LED with a total of 60 pieces causes distortion of the current waveform with THDi of 63.97% exceeding the standard value of IEEE Std 519-2014, with dominant harmonic currents in the 3rd order with a THDi of 74% and order 5 with a THDi of 37.6% and a THDv value of 2.44%, still below the 5.0% standard of IEEE Std 519-2014. This high THDi value has a negative impact on the low PF value of 0.722, which does not meet the power factor requirements of ≥ 0.85 according to PLN standards. And if the true power factor (TPF) value is calculated, the TPF value is 0.608 which is lower than the PF value of 0.722. The results obtained from the Matlab simulation show conformity to the results obtained from experimental measurements in the laboratory, namely: the simulated harmonic waveform approximates the measured harmonic waveform.


2018 ◽  
Vol 15 (1) ◽  
pp. 55-72
Author(s):  
Herlin Hamimi ◽  
Abdul Ghafar Ismail ◽  
Muhammad Hasbi Zaenal

Zakat is one of the five pillars of Islam which has a function of faith, social and economic functions. Muslims who can pay zakat are required to give at least 2.5 per cent of their wealth. The problem of poverty prevalent in disadvantaged regions because of the difficulty of access to information and communication led to a gap that is so high in wealth and resources. The instrument of zakat provides a paradigm in the achievement of equitable wealth distribution and healthy circulation. Zakat potentially offers a better life and improves the quality of human being. There is a human quality improvement not only in economic terms but also in spiritual terms such as improving religiousity. This study aims to examine the role of zakat to alleviate humanitarian issues in disadvantaged regions such as Sijunjung, one of zakat beneficiaries and impoverished areas in Indonesia. The researcher attempted a Cibest method to capture the impact of zakat beneficiaries before and after becoming a member of Zakat Community Development (ZCD) Program in material and spiritual value. The overall analysis shows that zakat has a positive impact on disadvantaged regions development and enhance the quality of life of the community. There is an improvement in the average of mustahik household incomes after becoming a member of ZCD Program. Cibest model demonstrates that material, spiritual, and absolute poverty index decreased by 10, 5, and 6 per cent. Meanwhile, the welfare index is increased by 21 per cent. These findings have significant implications for developing the quality of life in disadvantaged regions in Sijunjung. Therefore, zakat is one of the instruments to change the status of disadvantaged areas to be equivalent to other areas.


Background: Integrated disease management with self-management for Chronic Obstructive Pulmonary Disease (COPD) is effective to improve clinical outcomes. eHealth can improve patients’ involvement to be able to accept and maintain a healthier lifestyle. Eventhough there is mixed evidence of the impact of eHealth on quality of life (QoL) in different settings. Aim: The primary aim of the e-Vita-COPD-study was to investigate the effect of use of eHealth patient platforms on disease specific QoL of COPD patients. Methods: We evaluated the impact of an eHealth platform on disease specific QoL measured with the clinical COPD questionnaire (CCQ), including subscales of symptoms, functional state and mental state. Interrupted time series (ITS) design was used to collect CCQ data at multiple time points. Multilevel linear regression modelling was used to compare trends in CCQ before and after the eHealth intervention. Results: Of 742 invited COPD patients, 244 signed informed consent. For the analyses, we only included patients who actually used the eHealth platform (n = 123). The decrease of CCQ-symptoms was 0,20% before the intervention and 0,27% after the intervention; this difference was statistically significant (P=0.027). The decrease of CCQ-mental was 0,97% before the intervention and after the intervention there was an increase of 0,017%; this difference was statistically significant (P=0,01). No significant difference was found in the slopes of CCQ (P=0,12) and CCQ-function (P=0,11) before and after the intervention. Conclusion: The e-Vita eHealth platform had a potential beneficial impact on the CCQ-symptoms of COPD patients, but not on functional state. The CCQ-mental state remained stable after the intervention, but this was a deterioration compared to the improving situation before the start of the eHealth platform. In conclusion, this study shows that after the introduction of the COPD platform, patients experienced fewer symptoms, but their mental state deteriorated slightly at the same time. Therefore, health care providers should be aware that, although symptoms improve, there might be a slight increase in anxiety and depression after introducing an eHealth intervention to support self-management.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 152-152
Author(s):  
Afeez Hazzan

Abstract Family caregivers of older people living with dementia are relatives, friends, or neighbors who provide assistance related to this condition, but who are unpaid for the services they provide. Although caregiving could be personally rewarding, many caregivers report a high level of strain. Compared to caregivers of older adults who do not have dementia, family caregivers of older people living with dementia report lower quality-of-life (QoL). In a published systematic review examining the relationship between family caregiver QoL and the quality of care provided, only one study was found to be somewhat relevant. The study suggested that the primary reason for an absence of research into the link between family caregiver QoL and quality of care was the absence of a questionnaire for measuring quality of care in dementia. Therefore, any attempt to investigate the impact of caregiver QoL on the care provided to older people with dementia must first address the lack of an instrument to measure quality of care. To address this issue, we interviewed approximately 20 family caregivers in order to elicit feedback on measurements and interpretation of the quality of care provided by family caregivers of older people living with dementia. Content analysis of the interview transcripts revealed that the quality of relationships with family, caregiver availability to provide or supervise care, and availability of paid or volunteer help are important for the quality of care provided. These results have important implications, particularly for the development of an instrument to measure quality of care in dementia.


2003 ◽  
Vol 14 (04) ◽  
pp. 181-187 ◽  
Author(s):  
Christopher D. Bauch ◽  
Susan G. Lynn ◽  
Donald E. Williams ◽  
Michael W. Mellon ◽  
Amy L. Weaver

The impact of tinnitus and overall levels of distress were measured with three assessment tools for patients with tinnitus. The Tinnitus Handicap Inventory (THI), the Symptom Checklist-90-Revised (SCL-90-R) and an activities limitations questionnaire were administered to 53 audiology patients reporting tinnitus. Forty-three percent of these patients experienced either quality of life reductions associated with tinnitus, substantial perceived handicap, and/or a high level of distress. Results from the General Severity Index (GSI) of the SCL-90-R indicated that 25% of these patients displayed distress greater than that of the general medical population. The SCL-90-R can be a useful tool for audiologists working with tinnitus patients in assessing needs for referral for psychological or psychiatric counseling.


Author(s):  
Carlos Mena Canata ◽  
Rebeca Noemí Ruiz Vallejos

The objective of this study is to determine the impact of adenotonsillectomy on the quality of life of postoperative patients.The study is observational, cross-sectional, and retrospective. The files of all postoperative adenotonsillectomy patients in Otorhinolaryngology Service, Hospital de Clínicas, San Lorenzo Paraguay. The Obstructive sleep apnea – 18 questionnaire (OSA 18) was applied, asking patients about symptoms before and after surgery. An effective sample of 143 postoperative patients was obtained. The average age was 6.05 ± 2.08 years, 55.10% (81) were male and 44.89% (66) were female, 65.30% (96) were from urban areas and 34.69% (51) from the rural areas. The t test was performed for means of two paired samples, comparing the results of the Obstructive sleep apnea – 18 questionnaire surveys before and after surgery which presented a significant difference (p <0.05) with a tendency to improve the quality of life after surgery. It has been shown that there is a significant difference, a considerable improvement in the quality of life of patients after adenotonsillectomy.


Author(s):  
Marcel van Oijen ◽  
Gianni Bellocchi ◽  
Mats Höglind

There is increasing evidence that the impact of climate change on the productivity of grasslands will at least partly depend on their biodiversity. A high level of biodiversity may confer stability to grassland ecosystems against environmental change, but there are also direct effects of biodiversity on the quantity and quality of grassland productivity. To explain the manifold interactions, and to predict future climatic responses, models may be used. However, models designed for studying the interaction between biodiversity and productivity tend to be structurally different from models for studying the effects of climatic impacts. Here we review the literature on the impacts of climate change on biodiversity and productivity of grasslands. We first discuss the availability of data for model development. Then we analyse strengths and weaknesses of three types of model: ecological, process-based and integrated. We discuss the merits of this model diversity and the scope for merging different model types.


2020 ◽  
Vol 6 (3) ◽  
pp. 294-309
Author(s):  
Jamhur Poti ◽  
Mahadiansar Mahadiansar

Revitalizing traditional markets is a form of improving the quality of public space as a policy of the regional government in cooperation with local communities. The purpose of revitalizing traditional markets is not merely to improve the physical form of traditional markets but also to manage these traditional markets. The researcher raised a case study on the policy after revitalizing the Lembu Market, Tanjungpinang City, to what extent the policies that have been implemented before and after the market revitalization match the public's expectations, it is necessary to evaluate the programs that have been implemented. Researchers used policy evaluation techniques with a formal evaluation approach using Dunn 2018 theory. The research method used by researchers used library research, by carrying out a search of several library sources such as e-books, journals, websites, organizational reports, and other good documents. print and online relevant to the topic being evaluated. The results showed that the evaluation of the revitalization program for the beef slaughter market in the city of Tanjungpinang had not found the value of cross-impact analysis and discounting on the program so that the revitalization of traditional markets was only in the form of target mapping, value clarification and mapping of barriers that had become the impact of the revitalization policy of the traditional cattle slaughter market in Tanjungpinang City. The researcher also did not find Urgency in realizing the traditional market revitalization policy in order to change the characteristics of the market for the better.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Montse Romero-Mas ◽  
Anna Ramon-Aribau ◽  
Dyego Leandro Bezerra de Souza ◽  
Andrew M. Cox ◽  
Beni Gómez-Zúñiga

Caring for a person with dementia burdens family caregivers, and there is a close negative relationship between this burden and their quality of life (QoL). Research suggests that caregivers’ main needs are information and training about the disease and support from others experiencing the same situation, and Internet interventions hold considerable promise for meeting these needs. Virtual communities of practice (VCoPs) are Internet frameworks to share knowledge where members collaborate and achieve a sense of trust in the community. This paper seeks to evaluate the impact of participating in a VCoP (developed through an App) on the QoL of caregivers to people with Alzheimer’s. Results show QoL before and after the intervention changed significantly. The impact of VCoP on caregivers’ overall QoL is moderated by age and relation with the person with Alzheimer’s, specifically those over 65, and spouses. VCoPs allow interaction and knowledge sharing among caregivers which provide them mainly with information and support from peers helping them to meet their needs. Furthermore, caregivers’ QoL did not decrease when their relative deteriorated functionally, which could be due to the participation in VCoP. Although we found significant pre- and post differences in caregivers’ health literacy, we must report the ambiguous result that this variable only impacts on QoL’s physical domain. Participants also reported that they had a positive experience because the App was perceived to be a useful tool, because they could manage their own participation and they met peers and felt less lonely. Results suggest that participation in a VCoP impacts positively on caregivers’ QoL.


2022 ◽  
Vol 82 ◽  
Author(s):  
A. Hedfi ◽  
M. Ben Ali ◽  
A. Noureldeen ◽  
H. Darwish ◽  
T. Saif ◽  
...  

Abstract The main objective of the current study was to assess the impact of the water taken from the ‘Tunisian Refining Industries Company’ on meiobenthic nematodes, before and after a series of treatments in decantation basins followed by its discharge in Bizerte bay, Tunisia. The comparison of environmental parameters of the two types of water was clearly indicative of an improvement in the quality of treated waters after a significant reduction in their loads in hydrocarbons. Overall, the water retained a good quality after being treated by ‘Tunisian Refining Industries Company’ before discharge in the sea. At the end of the experiment, differential responses were observed according to the richness of sediment in organic matter and hydrocarbons. Thus, it was apparent that the nematode assemblage exposed to the treated waters was closer to controls and associated to higher values of abundance, than that under untreated ones. It was also assumed that the species Microlaimus honestus De Man, 1922, Paramonohystera proteus Wieser, 1956 and Cyartonema germanicum Juario, 1972 are sensitive bioindicators of bad environmental statues and of hydrocarbon presence in the environment. On the other hand, Metoncholaimus pristiurus (Zur Strassen, 1894) Filipjev, 1918 would rather be classified as a positive bioindicative species of this type of pollutants.


Sign in / Sign up

Export Citation Format

Share Document