7,932 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
Sähkömoottorin jäähdytysjärjestelmän kehittäminen
No full textTämän opinnäytetyön aiheena oli kehittää räjähdyssuojatun sähkömoottorin tuuletinjärjestelmää. Työn toimeksiantaja on Vaasassa sijaitseva IEC LV Motors, joka on osa ABB Oy:tä.
Opinnäytetyö tehtiin osana toimeksiantajan projektia, jossa kehitetään uuden sukupolven 160-kokoluokan räjähdyssuojattua sähkömoottoria. Tuuletinjärjestelmän ongelmana oli erillispuhallinmoottorin kiinnittäminen tuuletinsuojaan, koska tuuletinsuoja ei kestä erillispuhallinmoottorista aiheutuvia tärinöitä ja painoa.
Työn tavoitteena oli tutkia, olisiko mahdollista saada tuuletinmoottori mahdutettua uuden tuuletinsuojan sisälle kokonaan ja kiinnittää tuuletinmoottori laakerikilpeen eikä tuuletinsuojaan. Työ tehtiin ja suunniteltiin Siemens NX -ohjelmalla.The topic of this thesis was to develop a new cooling system for an explosion proof electric motor. The commissioner of this work is IEC LV Motors, located in Vaasa, which is part of ABB Oy.
This thesis was made as a part of the company’s own project to develop a new generation for a 160 sized explosion proof electric motor. Cooling systems problem was attaching fan motor to fan cover, because fan cover could not en-dure the weight and vibrations caused by the fan motor.
The goal of this work was to study if it was possible to fit the fan motor com-pletely within the fan cover and attach it to the bearing shield and not the fan cover. Work was made and designed with Siemens NX -application
Design of a Fan-Out Panel-Level SiC MOSFET Power Module Using Ant Colony Optimization-Back Propagation Neural Network
No full textA new panel-level silicon carbide (SiC) metal oxide semiconductor field effect transistor (MOSFET) power module was developed by using the fan-out and embedded chip technologies. To achieve the more effective thermal management and higher reliability under thermal cycling, a new optimization method called Ant colony optimization-back propagation neural network (ACO-BPNN) was developed for optimizing SiC modules, and contrast it with the Response Surface Method (RSM). First, the heat dissipations of SiC MOSFET with different redistribution layer (RDL) materials were simulated through the ANSYS finite element simulation. Then, the RSM was adopted to design the experiments for optimization. Third, the optimized design considering both junction temperature and thermal-mechanical stress is obtained using RSM and ACO-BPNN. The results show that: 1) compared with nano-silver, copper has a relatively good heat dissipation effect, but nano-silver has a better thermodynamic performance, and 2) ACO-BPNN can provide more accurate optimization results without having to construct a fitness function like RSM. After optimization, the thermal management and the thermal-mechanical stress can be improved by about 3% and 11%, respectively.</p
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
Bonomyces pseudoarnoldii L. Fan & N. Mao 2022, sp. nov.
No full textBonomyces pseudoarnoldii L. Fan & N. Mao, sp. nov. (Figs. 3, 4) MycoBank:— MB841875 Diagnosis:—differing from the phylogenetically and morphologically closest related species B. arnoldii by its crowded lamellae, absence of granules at the top of the stipe, well-differentiated mediostratum and stipitipellis, genetic profile, and distribution in north China. Etymology:—‘ pseudoarnoldii ’, refers to this species being similar to B. arnoldii. Holotype:— CHINA. Shanxi Province, Linfen City, Yicheng County, Zhongtiaoshan Mt., 1950 m elev., 8 July 2021, on the ground under Pinus armandi, N. Mao MNM 239 (BJTC FM1672). Description:— Pileus 12–49 mm, at first convex, then flat to slightly depressed or umbilicate; margin not striate, revolute or flat when young, later slightly uplifted and wavy, sometimes split; surface dry, finely to coarsely fibrillose near the margin, occasionally cracking into minute squamules towards the center; reddish brown (#b95d30) to dark brown (#a56829), pale orange (#e67028), sometimes light yellow (#f3bc9b) or dark reddish brown (#3f1010) in the center. Lamellae 1.5–3.0 mm broad, L = 40‒60, l = 1‒3, crowded, subdecurrent to decurrent, whitish (#ff0000), becoming beige (#f5f5dc), edge turning reddish brown (#b95d30) with age. Stipe central, 18–45 × 3–9 mm, terete, usually equal, occasionally inflated at the apex and slightly tapering at base, granules absent at the top, sometimes curved, longitudinally fibrillose, solid, pale white (#fafafa) to reddish brown (#b95d30) or pale orange (#ee9e6d), with a cluster of large white rhizomorphs at the base. Context white when young later pale brown under the pileus and stipe surface. Odor not recorded. Taste not recorded. Spore print white. Basidiospores [120/4/3] (6.5–)7–8.5(–9) × (4–)4.5–5.5(–6) μm (avg. ± SD = 7.6 ± 0.65 × 4.8 ± 0.57 μm), [Q = (1.35–) 1.40–1.75 (–1.90), Q av = 1.58 ± 0.16], mostly oblong-ellipsoid or amygdaliform in side-view, a few somewhat cylindrical, usually uni-guttulate, smooth, slightly thick-walled (0.3–0.6 µm), with a thick lateral apiculus. Basidia (27–)30–35(–37) × 5–8 μm, mostly 4–spored, occasionally 2–spored, cylindrical to clavate, mostly hyaline, with sterigmata 3–6 μm long. Subhymenium 10–15 µm thick, pavimentous (bottom of hymenophore), weakly developed, made of small polygonal elements 2–4 µm wide. Hymenopodium, 15–20 µm thick, slightly divergent, composed of slender hyphae 1.5–5 µm wide. Mediostratum 70–105 µm thick, well differentiated, regular, composed of parallel hyphae 3–9 μm diam, smooth, colorless. Hymenial cystidia not seen. Pileipellis a trichoderm, 120–150 µm thick, composed of parallel cylindrical to clavate hyphae, 3–11 μm in diam, smooth, with walls sometimes slightly thickened, with yellow to brown minute intracellular pigment, often with numerous cystidioid terminal elements measuring about 30–55 × 5–9(–13) μm, cylindrical to narrowly clavate or sometimes irregular, prostrate or erect, in fascicles. Subpellis not differentiated. Stipitipellis well-differentiated, 90–105 µm thick, composed of parallel hyphae 2.5–6 μm diam. with pale yellow to light brown content, thin-walled. Stipititrama well-differentiated, made of parallel hyaline hyphae 2.5–9.0 µm wide. Clamp connections present in all tissues. Habit, habitat and distribution:—Solitary or scattered, on the ground in conifer forests dominated by Pinus armandi, known from the north of China. Additional specimens examined:— CHINA. Shanxi Province, Linfen City, Yicheng County, Zhongtiaoshan Ms., 35°29’41’’N, 111°54’15’’E, 1950 m elev., 8 July 2021, on ground under Pinus armandi, N. Mao MNM 238 (BJTC FM1671); ibid. 35°29’51’’N, 111°55’1’’E, 1920 m elev., 8 July 2021, on ground under Pinus armandi, N. Mao MNM 240 (BJTC FM1673).Published as part of Mao, Ning, Lv, Jing-Chong, Zhao, Tao-Yu & Fan, Li, 2022, Bonomyces pseudoarnoldii (Biannulariaceae, Agaricales), a new species from China revealed by morphology, and multilocus phylogenetic analysis, pp. 69-78 in Phytotaxa 545 (1) on pages 72-76, DOI: 10.11646/phytotaxa.545.1.5, http://zenodo.org/record/652038
FIGURE 4 in Bonomyces pseudoarnoldii (Biannulariaceae, Agaricales), a new species from China revealed by morphology, and multilocus phylogenetic analysis
No full textFIGURE 4. Microscopic features of Bonomyces pseudoarnoldii (BJTC FM1672, holotype). a. Basidiospores b. Basidia c. Subhymenium, Hymenopodium and Mediostratum d. Pileipellis. Scale bars: a = 5 μm; b, d = 10 μm; c = 20 μm. Drawings and photo by: Ning Mao.Published as part of Mao, Ning, Lv, Jing-Chong, Zhao, Tao-Yu & Fan, Li, 2022, Bonomyces pseudoarnoldii (Biannulariaceae, Agaricales), a new species from China revealed by morphology, and multilocus phylogenetic analysis, pp. 69-78 in Phytotaxa 545 (1) on page 75, DOI: 10.11646/phytotaxa.545.1.5, http://zenodo.org/record/652038
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
Fiscal Prudence and Growth Sustainability: An Analysis of China's Public Debts
No full textThis paper analyses and assesses China's current fiscal system, including its basic institutional arrangements, the relationship between central and local governments, and the fiscal balance and public debt. This paper pays special attention to the local government borrowings that have increased dramatically in recent years, and tries to measure the overall public debt risk by including all kinds of eligible debts. This paper finds that although the large expansion of local government debt during the fiscal stimulation response to the global financial crisis was devastating, the all-inclusive total public debt to gross domestic product ratio remains under 50%, and as long as the local debt stops growing, the risk is quite manageable. This paper also points out that more attention should be paid to improving and reforming the Chinese fiscal system, particularly the reform of the fiscal relationship between central and local governments, and the legal framework for local government debt management.EconomicsSSCI5ARTICLE2202-220
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
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