130 research outputs found
Around the Grothendieck anabelian section conjecture
No full textThis is the author accepted manuscript. The final version is available from CUP via the DOI in this record We mostly survey recent results (including those of the author) on the Grothendieck anabelian section conjectur
Implementasi Alat Monitoring Saidi Dan Saifi Via Sms Dan Iot
No full textReliability is the ability of the system to deliver electricity to customers in appropriate or reasonable standards and quantities. In this case, the author makes a tool for implementing SAIDI and SAIFI monitoring tools via SMS and IoT to help improve electrical reliability, if there is damage or problems in the electricity distribution system to customers in low-voltage electrical panels 380 V/220 V, it can be handled faster by PLN field officers with an SMS notification system and make it easier to retrieve SAIDI and SAIFI monthly/annual index data by using the SD card data recap storage system and on the Blynk application making it easier to evaluate, analyze and improve the reliability of the electric power system network in the future, especially at PT. Adra Brilliant Rayon of Bengkalis City. In data collection for 2 weeks from July 15 to 29 at PHBTR next
to GH Hangtuah Rumbia st, found 4 interruptions with an average interruption time of 72,865 minutes and a repair rate of 0.0137240102, the time difference between sending SMS messages and SD card data for 4 interruptions with an
average time of 151,175 minutes
ANALYSIS OF THE RELIABILITY OF THE 20 KV DISTRIBUTION SYSTEM AT ULP DHARMO PERMAI USING THE SAIDI AND SAIFI METHODS
No full textThe quality of electrical energy received by customers is influenced by the distribution system. It requires an electric power distribution system with good reliability. An electric power distribution system can be said to be reliable if the disturbances and blackouts that occur within a certain period of time are below the established reliability index numbers. The measure of the reliability of a system can be expressed by calculating the SAIFI (System Average Interruption Frequency Index) and SAIDI (System Average Interruption Duration Index), namely how often the system experiences blackouts and how long the outages occur within a certain time span, namely one year. This study aims to analyze the reliability of the electric power distribution system at PT. PLN ULP Dharmo Permai is based on the SAIDI and SAIFI reliability index by using distribution disruption data that occurred during 2019. The steps taken by the author are collecting disturbance data, blackout data, and customer data obtained at PT. PLN (Persero) ULP Dharmo Permai. Then the results of these calculations are compared with the values according to the SPLN 68-2: 1986 and IEEE std 1366-2003 standards. At the ULP Dharmo Permai the Saidi and Saifi values are very good because they do not exceed the limits specified by SPLN 68-2: 1986 and IEEE std 1366 - 2003
Perancangan Dan Pembuatan Alat Pendeteksi Durasi Pemadaman Untuk Menentukansystem Average Interruption Duration Index(Saidi)
No full textDistribution system as a system of distribution of electric power aredirectly related to Subscriber should pay attention to the level of its reliability of elektirik of its reliability of electric power supply ie. Konsumen continuously. This research aims to determine the indexto mainstay SAIDI. System average Interruptin Duration Index (average Time index of a blackout), based on the duration of the blackout, as well as the number of subscribers on each penyulang distribution network The methods used for data retrieval from the tools that have been created using the assumptions, this tool uses a microcontroller as the brain programs from design tool designed and function to calculate the duration of his long dead lights. Data to calculate the condition of dead and alive are stored on the sd card. To find out the many distractions and business clients the whole number of customers then the author uses the assumption, that assumption takes from line three pasha IE R S T, third line from the testing assumptions as much as two days per line. From the assumption that data has been collected data on overall customer and customer data that is experiencing interference.in the get custumer data with 310 custumer overall distruption of the average amount of long and 88.57 disturbace duration dead lights 2.95 hoursand has calculated the value of custumer outages saidi hours/week/0.1
My view on and experience with Grothendieck\u27s anabelian geometry
No full textThis paper is based on the author\u27s talk at the Grothendieck conference at Chapman university on 26-05-2022. It is not a survey of anabelian geometry but rather exposes some of the personal views and experiences of the author with the topic.Chapter, to appear in the book : The Mathematical and Philosophical Legacy of Alexander Grothendiec
One Bad Apple Can Spoil Your {IPv6} Privacy
No full textIPv6 is being more and more adopted, in part to facilitate the millions of smart devices that have already been installed at home. Unfortunately, we find that the privacy of a substantial fraction of end-users is still at risk, despite the efforts by ISPs and electronic vendors to improve end-user security, e.g., by adopting prefix rotation and IPv6 privacy extensions. By analyzing passive data from a large ISP, we find that around 19% of end-users' privacy can be at risk. When we investigate the root causes, we notice that a single device at home that encodes its MAC address into the IPv6 address can be utilized as a tracking identifier for the entire end-user prefix-even if other devices use IPv6 privacy extensions. Our results show that IoT devices contribute the most to this privacy leakage and, to a lesser extent, personal computers and mobile devices. To our surprise, some of the most popular IoT manufacturers have not yet adopted privacy extensions that could otherwise mitigate this privacy risk. Finally, we show that third-party providers, e.g., hypergiants, can track up to 17% of subscriber lines in our study.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Cyber Securit
Station Area ZuidAs Amsterdam
No full textImprovement of the Station Area of the Zuidas in Amsterdam. Zooming out and elaboration of the Hotel function at the entrance of the Train Station.Hybride BuildingArchitectureArchitectur
Can REDD+ contribute to private sector development in sustainable fuelwood and charcoal production in Rwanda?
No full textThe expected increase in future demand of biomass feedstock in Rwanda cannot be met because of constraints at the supply side. This has a negative effect on the energy security for Rwandese in the future and the income generated for the Rwandan population involved in biomass feedstock production. There are, however, opportunities to stimulate the typically informal private sector in such a manner that the biomass energy production is made more sustainable. This thesis conducts research into the REDD+ mechanism (Reducing Emissions from Deforestation and Forest Degradation and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks (UN, 2011)) and the role it can play for the Rwandan biomass feedstock market. Next, an exploration is made of the current charcoal and fuelwood value chains to be able to better promote sustainable production of biomass. Then, an adapted version of business model generation theory from Osterwalder and Pigneur (2010) of Vastbinder, Kroesen, Blom, and Ortt (2011) is applied to generate sustainable business models. It is shown through a charcoal and a fuelwood cooperative business model that existing, improved and economically viable techniques exist in Rwanda which can be exploited to improve the sustainability of practices within the charcoal and fuelwood value chains; and leverage private investment. It is also shown that REDD+ can provide the financial argumentation for private smallholders to provide a tangible benefit of being in a cooperative, but that there is a lack of data available to prove it. Based on the research findings, the Government of Rwanda is recommended to build institutional capacities at different levels of Government in order to: (1)Align laws and policies applying in the different sectors involved in biomass energy production so that competition for land between energy, agriculture and forestry is decreased; (2)Develop and implement laws and policies specifically addressing charcoal and fuelwood in Rwanda which can be monitored uniformly and are applied consistently across the various levels of Government; (3)Promote increased social, economical and ecological benefits of improved charcoal and fuelwood production cooperatives to reach more formal organization of the charcoal and fuelwood sector and more equally distributed income across the value chains; (4)Gain insight in what the economic characteristics of the charcoal and fuelwood markets in Rwanda are, so that intervention to create long-term economic sustainability is founded on better reasoning; (5)Operationalize additional value of their project-involved activities, so that sustainable benefits of practical intervention can be proven and continued funding for the longer term can more easily be derived. Based on the research findings, it is recommended to DGIS (the Directorate General for International Cooperation) to: (1)Reconsider their food security definition to include domestic cooking energy for developing countries which are densely populated and rely on traditional biomass. The current food security definition increases competition between wood production for domestic energy provision and agricultural food production - without the energy to cook there are no means to achieve food security; (2)Convince the international developing aid community that a reconsideration of the food security definition is needed; (3)Provide aid to the Government of Rwanda through bilateral agreements for: a.Capacity building activities (e.g. institutional or business); b.Gaining an insight in the economic characteristics of the charcoal and fuelwood markets in Rwanda; (4)Develop guidelines for the REDD+ mechanism on which data can be collected in what way to be able to prove additional value of certain projects. Currently these guidelines do not exist. Hence, sustainable benefits of practical intervention are short term. This is because involved parties lack the time and resources to consider long-term sustainability – potentially through carbon finance – since short-term results are needed; (5)Follow up on the previous recommendation so that current and future funding of projects requires not just a focus on practical intervention, but focuses on proven long-term additionality of practices as well; (6)Research opportunities to develop a mechanism by which such supply-side interventions in woody, traditional biomass value chains can be funded. Although these interventions are beneficial in terms of sustainable development, the old-fashioned image of woodfuels and the complexities with terrestrial carbon – including forest carbon – calculations hamper the possibilities for funding of wood energy interventions at the supply side.Systems Engineering, Policy Analysis and ManagementEnergy & IndustryTechnology, Policy and Managemen
The root essential oil from the Tunisian endemic plant Ferula tunetana: Chemical composition, biological evaluation, molecular docking analysis and drug-likeness prediction
No full textOxidative stress is closely related to cancer aspects, such as the induction of gene muta-tions resulting from cellular injury and the effects on transcription and signal transduction factors. In addition, antibiotic resistance is also linked with oxidative stress, which could contribute to the selection of resistant bacterial strains. With this in mind, and considering that essential oils are well known to display antioxidant, antimicrobial, and cytotoxic activities, this study was destined to in-vestigate the chemical composition and to screen these properties for the root essential oil (REO) of the Tunisian endemic species Ferula tunetana Pomel ex Batt. The REO GC/MS analysis led to the identification of nine compounds, representing 94.5% of the total oil composition. The phytochem-ical profile of this essential oil (EO) was characterized by the dominance of sesquiterpenes, compris-ing 11.7% of sesquiterpene hydrocarbons and 82.8% of oxygenated sesquiterpenes. The three major constituents of the EO were caryophyllene oxide (33.9%), a-cyperone (13.9%), and 14-hydroxy-9- epi-(E)-caryophyllene (12.3%). REO showed a good antioxidant potential against DPPH (IC50 = 30.13 & PLUSMN; 0.28 & mu;g/mL), O2 & BULL;- (IC50 = 42.87 & PLUSMN; 0.81 & mu;g/mL) and H2O2 (IC50 = 48.03 & PLUSMN; 1.21 & mu;g/mL). Additionally, the antimicrobial activity results showed that REO had a strong an-tibacterial potential against all target microbial strains, including five Gram-negative, six Gram-positive bacteria, and two Candida species (MICs = 0.039-0.625 mg/mL). Furthermore, the ex-tracted EO was found to have good cytotoxic properties against five human cell lines viz. HT-29, HCT-116, HeLa, A549 and U937, with IC50 values ranging from 3.37 & PLUSMN; 0.02 to 46.66 & PLUSMN; 1.22 & mu;g/mL. The main REO constituents were docked to the human DNA topoisomerase IIa en-zyme and the in vitro cellular toxicities were rationalized. The drug-likeness of the main compounds identified in the studied EO was predicted. Overall, the results of the current study prove that the EO of F. tunetana roots has a noteworthy antioxidant potential and represents an interesting can-didate to treat infectious diseases and cancer. & COPY; 2023 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Structural Stabilities and Electronic Properties of High-Angle Grain Boundaries in Perovskite Cesium Lead Halides
No full textOrganometal trihalide perovskites are emerging as very promising photovoltaic materials, which is rivaling that of single crystal silicon solar cells despite their polycrystalline nature with relatively high density of grain boundaries (GBs). There is a lack of understanding of the effects of GBs on halide perovskites as their presence in silicon and other photovoltaic materials is generally detrimental to their photovoltaic properties. Using first-principles calculations, we systematically investigate the geometric structures of high-angle tilt GBs in halide perovskites CsPbX3 (X = Cl, Br, and I) starting from the coincidence site lattice model and refining using crystal shifts and lattice expansion. Electronic density of states calculations reveal that GBs in halides perovskites do not generate midgap states because Of the large distance between the unsaturated atoms and the atomic reconstructions in the GB region. However, we show that the GBs can induce different very shallow states near the valence band edge that can hinder hole diffusion. We further extend the results to MAPbI(3) GBs and also show their benign, effect on optoelectronic properties.National Natural Science Foundation of China [NSFC-51471004]; Doctoral Program of Higher Education of China [20130001110033]; department of Mechanical Engineering and Materials Science at the University of Pittsburgh; National Science Foundation [NSF OCI-1053575]; Graduate School of Peking UniversitySCI(E)ARTICLE31715-172212
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