2,343 research outputs found
From nominal to true a posteriori probabilities: an exact Bayesian theorem based probabilistic data association approach for iterative MIMO detection and decoding
No full textIt was conventionally regarded that the existing probabilistic data association (PDA) algorithms output the estimated symbol-wise a posteriori probabilities (APPs) as soft information. In this paper, however, we demonstrate that these probabilities are not the true APPs in the rigorous mathematicasense, but a type of nominal APPs, which are unsuitable for the classic architecture of iterative detection and decoding (IDD) aided receivers. To circumvent this predicament, we propose an exact Bayesian theorem based logarithmic domain PDA (EB-Log-PDA) method, whose output has similar characteristics to the true APPs, and hence it is readily applicable to the classic IDD architecture of multiple-input multiple-output (MIMO) systems using the general M-ary modulation. Furthermore, we investigate the impact of the PDA algorithms' inner iteration on the design of PDA-aided IDD receivers. We demonstrate that introducing inner iterations into PDAs, which is common practice in PDA-aided uncoded MIMO systems, would actually degrade the IDD receiver's performance, despite significantly increasing the overall computational complexity of the IDD receiver. Finally, we investigate the relationship between the extrinsic log-likelihood ratio (LLRs) of the proposed EB-Log-PDA and of the approximate Bayesian theorem based logarithmic domain PDA (AB-Log-PDA) reported in our previous work. We also show that the IDD scheme employing the EB-Log-PDA without incorporating any inner PDA iterations has an achievable performance close to that of the optimal maximum a posteriori (MAP) detector based IDD receiver, while imposing a significantly lower computational complexity in the scenarios considered
Temporal non-uniformity of LV wall expansion
No full textBackground: Early-diastolic left ventricular (LV) longitudinal expansion is delayed with diastolic dysfunction. We hypothesized that, in patients with heart failure (HF) regardless of LV ejection fraction (EF), there is diastolic temporal non-uniformity with a delay of longitudinal relative to circumferential expansion. Methods and Results: Echocardiography was performed in 143 HF patients: 50 with preserved EF (HFpEF) and 93 with reduced EF (HFrEF) and 31 normal controls. The delay of early-diastolic mitral annular velocity from the mitral Doppler E (TE-e′) was measured as a parameter of the longitudinal-expansion delay. The delay of the longitudinal early-diastolic global strain rate (SRE) relative to circumferential SRE (DelayC-L) was calculated as a parameter of temporal non-uniformity. Intra LV pressure difference (IVPD) was estimated by using color M-mode Doppler data as a parameter of LV diastolic suction. Although normal controls had symmetrical LV expansion in early diastole, TE-e′ and DelayC-L were significantly prolonged in HF regardless of EF (P<0.01 vs controls for all). Multivariate analysis revealed that DelayC-L was the independent determinant of IVPD among the parameters of LV geometry and contraction (β=-0.21, P<0.05). Conclusion: An abnormal temporal non-uniformity of early-diastolic expansion is present in HF regardless of EF, which was associated with reduced LV suction
Ltd.“Apranga LV”, Ltd.“Apranga BPB LV” and Ltd.“Apranga PLV” financial situation Assessment and Comparison
No full textDarba tēma: SIA ,,Apranga LV’’, SIA ,,Apranga BPB LV’’ un SIA ,,Apranga PLV’’ finansiālās situācijas novērtējums un salīdzinājums Darba mērķis ir uz teorētisko un praktisko materiālu pamata veikt uzņēmumu SIA ,,Apranga LV’’, SIA ,,Apranga BPB LV’’ un SIA ,,Apranga PLV’’finansiālā stāvokļa novērtēšanu un salīdzināšanu, atklāt trūkumus, nepilnības, problēmas un izstrādāt priekšlikumus trīs pētāmo uzņēmumu finansiālā stāvokļa uzlabošanai. Diplomdarbā tiek atklāta būtiska mātes sabiedrības ietekme uz pētāmo meitas uzņēmumu bilances rādītājiem. Darbs kopumā izklāstīts 68 lappusēs, tajā ir 28 tabulas.Theme of the paper: Ltd. ,,Apranga LV’’, Ltd. ,,Apranga BPB LV’’ and Ltd. ,,Apranga PLV’’ financial situation Assessment and Comparison Type of the paper: Diploma paper The aim of this paper is: On theoretical and practical material basis, accomplish Ltd. ,,Apranga LV’’, Ltd. ,,Apranga BPB LV’’ and Ltd. ,,Apranga PLV’’ financial situation assessment, reweal weaknesses, flaws, problems and develop proposals to the companies for financial situation improvements. In the diploma paper, author identifies the significant influence of the parent company, of the subsidiaries under investigation, on the balance sheet ratios. The paper consists of 68 pages with 28 tables
Container LV/MV switchgears
No full textIn this thesis author discuss main facilities of switchgear-rooms placed into metallic containers based on ISO containers primary used for transport. In the beginning of this thesis, author writes about the basic requirements needed for realization of switchgear-rooms placed into metallic containers. Paragraph includes parameters of ISO containers, benefits and necessary modifications of containers for substations. Author continues with environment impact of this solution. In the next paragraph author describes most important electrical devices, machines and components such as HV and LV ABB switchgears, transformers and other used devices and components. Next part deals with dimensions of holes for cables, air-conditioning and ventilators and calculations for light and air-conditioning proposal for concrete substation solved for SNOS in Salavat. Final part includes DIAlux export to show light intensity in different nodes of grid in switchgear room. Enclosure contains pictures and photographs for a better understanding of this unique solution and tables for proposal of heat profits from walls
Achieving full diversity in multi-antenna two-way relay networks via symbol-based physical-layer network coding
No full textThis paper considers physical-layer network coding (PNC) with M-ary phase-shift keying (MPSK) modulation in two-way relay channel (TWRC). A low complexity detection technique, termed symbol-based PNC (SPNC), is proposed for the relay. In particular, attributing to the outer product operation imposed on the superposed MPSK signals at the relay, SPNC obtains the network-coded symbol (NCS) straightforwardly without having to detect individual symbols separately. Unlike the optimal multi-user detector (MUD) which searches over the combinations of all users’ modulation constellations, SPNC searches over only one modulation constellation, thus simplifies the NCS detection. Despite the reduced complexity, SPNC achieves full diversity in multi-antenna relay as the optimal MUD does. Specifically, antenna selection based SPNC (AS-SPNC) scheme and signal combining based SPNC (SC-SPNC) scheme are proposed. Our analysis of these two schemes not only confirms their full diversity performance, but also implies when SPNC is applied in multi-antenna relay, TWRC can be viewed as an effective single-input multiple-output (SIMO) system, in which AS-PNC and SC-PNC are equivalent to the general AS scheme and the maximal-ratio combining (MRC) scheme. Moreover, an asymptotic analysis of symbol error rate (SER) is provided for SC-PNC considering the case that the number of relay antennas is sufficiently large
First person – Zhiyi Lv
No full textABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Zhiyi Lv is the first author on ‘A ‘molecular guillotine’ reveals an interphase function of Kinesin-5’, published in Journal of Cell Science. Zhiyi is a postdoctoral fellow in the lab of Jörg Groβhans at Göttingen University, Germany, investigating the mechano-biology of Drosophila morphogenesis.</jats:p
Impact of Dynamic Tariffs for Smart EV Charging on LV Distribution Network Operation
No full textWith a growing share of electric vehicles (EVs) in our distribution grids, the need for smart charging becomes indispensable to minimise grid reinforcement. To circumvent the associated capacity limitations, this paper evaluates the effectiveness of different levels of network constraints and different dynamic tariffs, including a dynamic network tariff. A detailed optimisation model is first developed for public charging electric vehicles in a representative Dutch low voltage (LV) distribution network, susceptible to congestion and voltage problems by 2050 without smart charging of EVs. Later, a detailed reflection is made to assess the influence of the modelled features on the distribution system operator (DSO), charge point operator (CPO) costs, and the EVs' final state-of-charge (SOC) for both mono- (V1G) and bi-directional (V2G) charging. Results show that the dynamic network tariff outperforms other flat tariffs by increasing valley-filling. Consequently, compared to regular day-ahead pricing, a significant reduction in the frequency of congestion in the lines is achieved. In addition, V2G ensures the joint optimum for different stakeholders causing adequate EV user satisfaction, decreased CPO costs compared to conventional charging and fewer violations of grid constraints for the DSOs.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.Intelligent Electrical Power GridsElectrical Sustainable Energ
Factors influencing consumer behaviour choosing SIA “Gym LV” services.
No full textBakalaura darba tēma ir “Patērētāju rīcību ietekmējoši faktori izvēloties SIA “Gym LV” pakalpojumus”. Darba mērķis, pamatojoties uz patērētāju rīcību teoriju, veiktā pētījuma rezultātiem, izanalizēt iegūtos datus, izdarīt secinājumus un sniegt priekšlikumus SIA “Gym LV” pakalpojuma darbības uzlabošanai. Darba pirmajā nodaļā aprakstītas patērētāju rīcību veicinošie faktori. Otrajā nodaļā autors apraksta SIA “Gym LV” saimniecisko darbību, procesus un attīstību. Trešajā nodaļā izanalizēti gūtie rezultāti. No aprakstītās teorijas un gūtajiem rezultātiem izdarīti secinājumi un izvirzīti priekšlikumi. Patērētājam, izvēloties sev piemērotāko sporta klubu, pievērš uzmanību trīs galvenajiem faktoriem – cena, atrašanās vieta un darba laiks. Neatkarīgi kādas ir atsauksmes internetā par pētāmo uzņēmumu, tās ietekmē vismazāk patērētāju lēmumu pieņemšana.The topic of the bachelor thesis is "Factors influencing consumer behaviour choosing SIA "Gym LV" services ". The aim of the thesis, based on the theory of consumer behaviour, results of the conducted research, analyse the data, make conclusions and make proposals for SIA "Gym LV" to improve services. The first chapter of the thesis describes factors influencing consumer behaviour. In the second chapter author describes economic activity, processes and development of SIA "Gym LV”. The third chapter analyse the results obtained. In the end conclusions and proposals are drawn from the theory and the results. There are three main factors that consumers look for when choosing the right gym for them - price, location and working hours. Regardless of the online reviews of the company, reviews have the least influence on consumer decision-making
Impact of line length on the operation of overvoltage protection in LV networks
No full textAbstractThis paper deals with analysing the impact of LV lines impedance on the operation of overvoltage protection, especially on the operation of gas discharge arresters. A model of the overvoltage protection with all elements (gas discharge arrester and metal-oxide surge arrester) was developed within a Simulink/Matlab environment for this purpose. This model of LV line is presented as a model for the computation of transients. Computations were carried out for various line lengths and various combinations of overvoltage protection elements. On the basis of analyzing the models responses, an analysis was made on the impact of the impedance of LV lines on the ability of self-extinguishing the gas discharge arrester. Some additional measures are also proposed for achieving the proper operation of overvoltage protection
Выбор поставщика светового и звукового оборудования для организации массовых развлекательных мероприятий "LV Party"
No full textДанная выпускная квалификационная работа направлена на решение проблемы выбора поставщика светового и звукового оборудования для компании по организации массовых развлекательных мероприятий «LV Party».
В исследовании представлены различные методы для подбора наиболее подходящего поставщика.
Так как для компании «LV Party» важен учет нескольких критериев при выборе поставщика, автор исследования рассматривает методы для решения многокритериальной задачи.
После изучения профессиональной и научной литературы, автор выбрал метод анализа иерархий для применения в компании. Данный метод позволил сравнить три альтернативы компаний-поставщиков, с учётом 5 выбранных критериев.
В результате расчетов автор смог выбрать одного поставщика оборудования для компании, который является наиболее подходящим для нее.The following thesis paper is focused on solving the problem of choosing a supplier of light and sound equipment for the company that is organizing mass entertainment events "LV Party".
The study explores various methods for selecting the most suitable supplier.
Since for the company "LV Party" it is very important to take into account several criteria while choosing a supplier, the author of the study was looking for those methods which can solve a multi-criteria problem.
After studying professional and scientific literature, the author chose the hierarchy analysis method for application in the company. This method allowed to compare three alternatives of supplier companies according to 5 selected criteria.
As a result, the author was able to select one supplier for the company, which is most suitable for it
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