457 research outputs found

    Domestic heat pump

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    Bakalářská práce zabývající se tématem „Tepelná čerpadla a vytápění RD“ je rozdělena do čtyř hlavních částí. První část stručně popisuje princip fungování a jednotlivé druhy tepelných čerpadel (typy voda – voda, vzduch – voda, země – voda) včetně výhod a nevýhod jejich vyuţití. Funkce tepelných čerpadel spočívá zejména ve vytápění rodinných domů a vyuţití k ohřevu teplé uţitkové vody. Je zde popsán přenos tepla mezi kondenzátorem a topným potrubím. Druhá část zahrnuje návrh pouţití konkrétního tepelného čerpadla, stručný popis vybraného objektu a výpočet tepelných ztrát objektu. Třetí část věnuje pozornost výpočtu energetické náročnosti budovy. Ekonomické zhodnocení zvoleného systému a finanční návratnost jsou obsaţeny ve čtvrté části této práce.The aim of the Bachelor's thesis is the ,,Heat pumps and house heating " . The thesis is divided into four main parts. The first part briefly describes the principle of operation and the types of heat pumps (The variants are water to water, air to water, earth to water), including the advantages and disadvantages of their use. Heat pumps are effective solutions to home and hot water heating. The part describes the heat transfer between the condenser and the heating pipes. The second part includes a proposal for using the specific heat pump, a brief description of the selected object and calculate the heat loss. The third part pays attention to calculating the energy performance of buildings. Economic evaluation of the selected system and financial returns are contained in the fourth part of this work.

    Disintegration of sludge thickened by flotation

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    Ústředním tématem této diplomové práce je zkoumání vlivu desintegrace čistírenského kalu na produkci bioplynu při procesu anaerobní fermentace. V úvodní teoretické části seznamuje s problematikou a jednotlivými metodami pouţívanými při čištění odpadních vod, ukazuje zjednodušený popis čistíren odpadních vod i dílčích zařízení. Následuje výčet některých způsobů zpracování čistírenského kalu i moţnosti jeho vyuţití. V dalších kapitolách je uveden podrobný popis vlastního procesu anaerobní fermentace včetně důleţitých faktorů, které tento proces ovlivňují. V textu je ukázáno porovnání aerobní a anaerobní fermentace i ekologický pohled na problematiku. Důleţitou součástí je zpracovaná problematika desintegrace spolu s uvedením a popisem některých desintegračních metod a zařízení. Stěţejní část práce tvoří popis provedených experimentů, během nichţ byl sledován nárůst mnoţství bioplynu při anaerobní fermentaci v závislosti na desintegraci čistírenského kalu. Následovně je uvedeno vyhodnocení uvedených experimentů společně s výpočty ekonomické stránky procesu desintegrace provedeného v laboratorních podmínkách.The main topic of this thesis is a research of influence of disintegration of sewage sludge on the production of biogas during the process of anaerobic fermentation. The theoretical part deals with issues and specific methods used during the process of waste water cleaning, furthermore it contains simplified description of waste water treatment plants and particular devices. The number of ways of processing sewage sludge and its potential utilization id also discussed. Following parts of the thesis analyze in detail my own process of anaerobic fermentation including important factors influencing this process. Comparison of aerobic and anaerobic fermentation and ecological perspective on the issue are included in this part. Another important part of the thesis deals with disintegration and description of the disintegration methods and devices. The fundamental part implies the analysis of the executed experiments. Experiments analyze the growth of biogas during anaerobic fermentation depending on the disintegration of sewage sludge. After that the evaluation of the experiments is stated together with economical calculations of the disintegration process executed in laboratory conditions.

    W-Cr solid solution: Comparison of alloying in SPS and by ball milling

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    Tungsten alloys currently represent prospective candidates to replace tungsten in the first wall applications in future fusion facilities. They are anticipated to suppress unfavorable mechanical properties of commercially pure tungsten and/or to gain advantages such as ability of self-passivation under accidental conditions. The self-passivating alloys are designed to minimize possible consequences related mainly to a LOCA (Loss of Coolant Accident) event with simultaneous air ingress into the reactor vessel. Please click Additional Files below to see the full abstract

    THIN NITRIDE LAYERS AS PERMEATION BARRIERS

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    Permeation barriers represent one of the crucial fields in materials development for thermonuclear fusion. Primary objective of the barriers is to suppress the permeation of hydrogen isotopes (mainly tritium) from future thermonuclear fusion facilities. Secondary objective is to reduce hydrogen retention in structural materials, potentially also improving their corrosion resistance. Expected reactor conditions put high demands on the material, as well as on the final barrier quality. Key properties are tritium permeation reduction, absence of defects (especially cracks), high-temperature stability and corrosion resistance, and compatibility with structural materials (mostly ferritic-martensitic steels). Regarding industrial scale production, ability of the deposition method to coat large complex surfaces is desirable. Thin nitride layers, identified as promising permeation barriers, were prepared by diffusion-based nitridation and physical vapour deposition (PVD) and characterized

    Limited Progress in Improving Gender and Geographic Representation in Coral Reef Science

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    Despite increasing recognition of the need for more diverse and equitable representation in the sciences, it is unclear whether measurable progress has been made. Here, we examine trends in authorship in coral reef science from 1,677 articles published over the past 16 years (2003–2018) and find that while representation of authors that are women (from 18 to 33%) and from non-OECD nations (from 4 to 13%) have increased over time, progress is slow in achieving more equitable representation. For example, at the current rate, it would take over two decades for female representation to reach 50%. Given that there are more coral reef non-OECD countries, at the current rate, truly equitable representation of non-OECD countries would take even longer. OECD nations also continue to dominate authorship contributions in coral reef science (89%), in research conducted in both OECD (63%) and non-OECD nations (68%). We identify systemic issues that remain prevalent in coral reef science (i.e., parachute science, gender bias) that likely contribute to observed trends. We provide recommendations to address systemic biases in research to foster a more inclusive global science community. Adoption of these recommendations will lead to more creative, innovative, and impactful scientific approaches urgently needed for coral reefs and contribute to environmental justice efforts.We acknowledge the contributions of the many unrecognized and undervalued individuals in coral reef research whose efforts have made it possible for the field to progress. These scientists have collected data, translated across languages, coordinated field work, welcomed foreign visitors to their countries, shared ideas, trained and mentored students, become friends, inspired, and built the foundation for the discipline we know today. We acknowledge the work of all coral reef scientists who continue day after day to pursue equity, inclusion, and justice in the field and for their colleagues and themselves.Ye

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Search for stop and higgsino production using diphoton Higgs boson decays

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    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

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    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe
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