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Evaluation of Voltage Sag Impact by Method of Fault Position in Distribution System with ITIC curve / การประเมินผลกระทบของแรงดันตกชั่วขณะโดยใช้หลักการระบุตำแหน่ง ความผิดพร่องในระบบจำหน่ายด้วยเส้นโค้ง ITIC
No full textบทคัดย่อแรงดันตกชั่วขณะ คือ ปัญหาคุณภาพอย่างหนึ่งสำหรับระบบจำหน่ายไฟฟ้าแบบเหนือดินซึ่งมีโอกาสเกิดความผิดพร่อง หรือการลัดวงจร ผลกระทบของแรงดันตกชั่วขณะเนื่องจากความผิดพร่องหรือการลัดวงจรขึ้นอยู่กับขนาดกระแสและระยะเวลา ในการกำจัดความผิดพร่องของอุปกรณ์ป้องกัน ปัจจัยทั้งสองดังกล่าวทำให้ทราบถึงระดับความลึกและระยะเวลาของการเกิดแรงดัน ตกชั่วขณะ ด้วยการอ้างอิงกับกราฟ ITIC เราจะทราบว่าอุปกรณ์ที่มีความไวที่เชื่อมต่ออยู่ ณ บัสที่สนใจ สามารถทำงานได้อย่างเหมาะสมหรือไม่ บทความนี้นำเสนอวิธีการระบุตำแหน่งของความผิดพร่องเพื่อให้ได้ขนาดและจำนวนครั้งของการเกิดเหตุการณ์แรงดันตก ซึ่งอ้างอิงกับข้อมูลที่ทราบค่าแน่นอนและข้อมูลเชิงสุ่มของระบบ วิธีที่พัฒนาขึ้นได้ทำการทดสอบกับระบบจำหน่าย Roy Billinton Test System (RTBS) ผลการจำลองเหตุการณ์ที่ได้รับเป็นประโยชน์อย่างมากและเป็นแนวทางสำหรับผู้ใช้ไฟฟ้าในการตัดสินใจหาจุดสมดุลระหว่างต้นทุนในการป้องกันเหตุการณ์แรงดันตกชั่วขณะและผลกระทบทางเศรษฐกิจเนื่องจากแรงดันตกชั่วขณะ คำสำคัญ: แรงดันตกชั่วขณะ การระบุตำแหน่งความผิดพร่อง เส้นโค้ง ITIC AbstractVoltage sag is one of the main power quality problems in overhead distribution systems which are exposed to faults or short circuits. The effects of voltage sag from fault or short circuit generally depend on fault current magnitude and clearing time of protective device. These two factors determine the depth and duration of voltage sag. With reference to the ITIC curve, it can be determined whether sensitive equipment connected at the bus of interest can function properly This paper presents a method of fault position to obtain the magnitude of voltage and the number of voltage sag events based on deterministic data and statistical data of the system. The developed methodology was tested with the Roy Billinton Test System (RTBS). The simulation results obtained are very useful and can be served as a guideline for customers to justify the optimal balance between the cost of investment to guard against voltage sag events and the economic loss due to voltage sag events. Keywords: Voltage sag, Fault Position, ITIC curv
The Developmental Periods of Mass Media from the Central Region, to the Northeast Region and to the Thai-So Ethnic Group of Kusuman District
Get PDFThe objective of this article is to study the developmental periods of mass media from the central region, to the northeast region and to the Thai-So community of Kusuman district. Purposive sampling technique was used for selecting 35 key informants. The research instrument was semi-structured interview. All raw materials were analyzed by content analysis. The research findings revealed that not only was the developmental periods of mass media from the central region, to the northeast region, and to the Thai-So community of Kusuman district at different times, but was also influenced by various driving forces. Moreover, the time scales of mass media development from the central to the northeast region and from the northeast region to the Thai-So community of Kusuman district were likely to continue to be reduced. Namely, the journey time of newspaper from the central region to the northeast region was around 116 years, followed by radio in around 10 years, television 7 years, internet 6 years, and satellite television 5 years. Similarly, the journey time of newspaper from the northeast region to the Thai-So community of Kusuman district was around 14 years, followed by television and internet in around 8 years, radio 7 years and satellite television 6 years. Therefore, this research predicts that, in the digital age, new forms of digital media-such as smart phones, tablets, Google glasses, smart watches and so forth - will become more rapidly proliferated into the northeast region and the Thai-So community of Kusuman district until there will be no difference between their arrival times. More Interestingly, all types of mass media - including newspaper, radio, television, satellite television and Internet - were available within the Thai-So community of Kusuman district but the Thai-So people are likely to be exposed to radio and television to a greater extent than other media. It was fair to say that they are likely to access mass media that requires no skills. Keywords: The Developmental Periods of Mass Media, The Central Region, The Northeast Region, The Thai-So Community of Kusuman District, Media Exposure
Diphoton Signatures from Heavy Axion Decays at the CERN Large Hadron Collider
No full textRecently, the LHC collaborations, ATLAS and CMS, have announced an excess in the diphoton channel with local significance of about 3σ around an invariant mass distribution of ∼750 GeV, after analyzing new data collected at centre-of-mass energies of √s = 13 TeV. In this Letter, we present a possible interpretation of such a signature, within the framework of a minimal UV-complete model with a massive singlet pseudo-scalar state a that couples to a new TeV-scale coloured vector-like fermion F, which has a large exotic hypercharge quantum number. The pseudo-scalar state a might be a heavy pseudo-Goldstone boson, such as a heavy axion, which decays into two photons and whose mass lies around the excess region. The mass of the CP-odd state a and its coupling to F may be due to non-perturbative topological effects, which break the original Goldstone shift symmetry dynamically. The possible role of the heavy axion a in the radiative generation of the seesaw Majorana scale and in the solution to the so-called strong CP problem are briefly discussed
Mental health service changes, organisational factors, and patient suicide in England in 1997–2012: a before-and-after study
No full textBackground Research into which aspects of service provision in mental health are most eff ective in preventing suicide is sparse. We examined the association between service changes, organisational factors, and suicide rates in a nationalsample. Methods We did a before-and-after analysis of service delivery data and an ecological analysis of organisational characteristics, in relation to suicide rates, in providers of mental health care in England. We also investigated whether the eff ect of service changes varied according to markers of organisational functioning. Findings Overall, 19 248 individuals who died by suicide within 12 months of contact with mental health services were included (1997–2012). Various service changes related to ward safety, improved community services, staff training, and implementation of policy and guidance were associated with a lower suicide rate after the introduction of thesechanges (incidence rate ratios ranged from 0·71 to 0·79, p<0·0001). Some wider organisational factors, such as nonmedical staff turnover (Spearman’s r=0·34, p=0·01) and incident reporting (0·46, 0·0004), were also related to suicide rates but others, such as staff sickness (–0·12, 0·37) and patient satisfaction (–0·06, 0·64), were not. Service changes had more eff ect in organisations that had low rates of staff turnover but high rates of overall event reporting. Interpretation Aspects of mental health service provision might have an eff ect on suicide rates in clinical populations but the wider organisational context in which service changes are made are likely to be important too. System-wide change implemented across the patient care pathway could be a key strategy for improving patient safety in mental health care
Genome-wide association analysis identifies three new susceptibility loci for childhood body mass index.
No full textA large number of genetic loci are associated with adult body mass index. However, the genetics of childhood body mass index are largely unknown. We performed a meta-analysis of genome-wide association studies of childhood body mass index, using sex- and age-adjusted standard deviation scores. We included 35,668 children from 20 studies in the discovery phase and 11,873 children from 13 studies in the replication phase. In total, 15 loci reached genome-wide-significance (P-valu
Transient receptor potential vanilloid 1 expression and function in splenic dendritic cells: a potential role in immune homeostasis
No full textNeuro-immune interactions, particularly those driven by neuropeptides, are increasingly implicated in immune responses. For instance, triggering calcium-channel transient receptor potential vanilloid 1 (TRPV1) on sensory nerves induces the release of calcitonin-gene-related peptide (CGRP), a neuropeptide known to moderate dendritic cell activation and T helper cell type 1 polarization. Despite observations that CGRP is not confined to the nervous system, few studies have addressed the possibility that immune cells can respond to well-documented 'neural' ligands independently of peripheral nerves. Here we have identified functionally relevant TRPV1 on primary antigen-presenting cells of the spleen and have demonstrated both calcium influx and CGRP release in three separate strains of mice using natural agonists. Furthermore, we have shown down-regulation of activation markers CD80/86 on dendritic cells, and up-regulation of interleukin-6 and interleukin-10 in response to CGRP treatment. We suggest that dendritic cell responses to neural ligands can amplify neuropeptide release, but more importantly that variability in CGRP release across individuals may have important implications for immune cell homeostasis
Urban growth and spatial restructuring patterns: The case of Yangtze River Delta region, China
No full textThe year 1995 has been widely identified as a watershed in China’s urbanisation process. The period before was deemed as ‘urbanisation from below’ with a focus on small cities and towns, whereas the period afterwards has been characterised by the ‘land-centred development’ of large cities. This paper argues that there have been further spatial and temporal differentiations since 2000. By adopting a city-regional perspective of urban land expansion, the urban growth and spatial-restructuring process of different levels of cities in Yangtze River Delta Region were examined. Different indicators and technical measures such as spatial autocorrelation analysis and Geographic Information System (GIS) mapping analysis were employed to examine growth rates, growth intensity levels and the spatial clustering patterns of 15 city-regions over three time periods between 1985 and 2007. Through the development of a unified land classification system with satellite images, and the use of the GIS grid-overlay method, our analysis overcomes various identified methodological problems of previous research
Flood resilience technology in Europe: identifying barriers and co-producing best practice
No full textFlood resistance and resilience technologies hold considerable potential to limit the damage caused by flooding. Resistance technologies generally aim to keep water out of buildings, while resilient measures may allow ingress but create the conditions for a quicker recovery of individuals, communities and buildings. However despite their potential contribution to flood risk management, their use remains uncommon. The paper draws upon pan-European research with local communities at risk and their representatives, and professional stakeholders working at a more strategic scale, to explore the barriers to use and describe the co-production of new best practice. The paper interrogates the issues in terms of: level of awareness, degree of acceptance and the integration into decision making. We found that even where awareness was high there was a reluctance to use these measures. This is due to issues related to comparability, costs, installation, performance and maintenance. The research also revealed that flood risk management policy and practice has struggled to incorporate this emergent approach and that many individuals at risk are reluctant to take responsibility and protect their properties in this way. In response, the paper details how good practice guidance – the ‘Six Steps approach’ – was co-produced with key stakeholders to facilitate the wider contribution of FRe to flood risk management