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Data-driven diagnosis of high temperature PEM fuel cells based on the electrochemical impedance spectroscopy: Robustness improvement and evaluation

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Journal of Energy chemistry 2024年第9期96卷 544-558页

作者： Dan Yu Xingjun Li Samuel simon Araya simon Lennart Sahlin Vincenzo Liso Department of Energy Aalborg UniversityAalborg 9220Denmark Walker Department of Mechanical Engineering The University of Texas at AustinAustinTX 78712USA Materials Research and Technology Development Luxembourg Institute of Science and Technology(LIST)4422 BelvauxLuxembourg

Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (EcM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the EcM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_c) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which sug

关键词： PEM fuel cell Data-driven diagnosis Robustness improvement and evaluation Electrochemical impedance spectroscopy

Experimental and Numerical Analysis of a PcM-Integrated Roof for Higher Thermal Performance of Buildings

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Journal of Thermal Science 2024年第2期33卷 522-536页

作者： simon François RUIZ-VALERO Letzai GIRARD Aymeric GALLEGUILLOS Hector centro de Desarrollo Urbano Sustentable(cEDEUS) Pontificia Universidad Católica de Chile7500000SantiagoChile Facultad de ciencias e Ingeniería Pontificia Universidad Católica Madre y Maestra(PUCMM)10103Santo DomingoDominican Republic LMGc IMT Mines AlesUniv MontpellierCNRS30100AlèsFrance Facultad de Ingeniería y ciencias Universidad Adolfo Ibañez2520000Viña del MarChile centro de Desarrollo Energético Antofagasta(cDEA) Universidad de Antofagasta1240000AntofagastaChile

Phase change materials(PcMs) designate materials able to store latent *** change state from solid to liquid over a defined temperature *** process is reversible and can be used for thermo-technical *** present paper aims to study the thermal performance of an inorganic eutectic PcM integrated into the rooftop slab of a test room and analyze its potential for building thermal *** experiment is conducted in two test rooms in Antofagasta(chile) during summer,fall,and *** PcM is integrated into the rooftop of the first test room,while the roof panel of the second room is a sealed air *** work introduces a numerical model,which is built using the finite difference method and used to simulate the rooms' thermal *** thermal simulations of the PcM room are performed for other chilean locations to evaluate and compare the capability of the PcM panel to store latent heat thermal energy in different *** show that the indoor temperature of the PcM room in Antofagasta varies only 21.1℃±10.6℃,while the one of the air-panel room varies 28.3℃±18.5℃.Under the experiment's conditions,the PcM room's indoor temperature observes smoother diurnal fluctuations,with lower maximum and higher minimum indoor temperatures than that of the air-panel *** simulations in other cities show that the PcM panel has a better thermal performance during winter,as it helps to maintain or increase the room temperature by some degrees to reach comfort *** demonstrates that the implementation of such PcM in the building envelope can effectively reduce space heating and cooling needs,and improve indoor thermal comfort in different climates of chile.

关键词： phase change material thermal energy storage building space heating and cooling energy efficiency designbuilder

Exploring a New Lifetime Distribution for Modelling the Waiting Time of Bank customers

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Journal of Applied Mathematics and Physics 2024年第1期12卷 194-209页

作者： simon A. Ogumeyo Jacob c. Ehiwario Festus c. Opone Department of Mathematics Delta State University of Science and Technology Ozoro Nigeria Department of Statistics University of Delta Agbor Nigeria Department of Statistics Delta State University of Science and Technology Ozoro Nigeria

The fitting of lifetime distribution in real-life data has been studied in various fields of research. With the theory of evolution still applicable, more complex data from real-world scenarios will continue to emerge. Despite this, many researchers have made commendable efforts to develop new lifetime distributions that can fit this complex data. In this paper, we utilized the KM-transformation technique to increase the flexibility of the power Lindley distribution, resulting in the Kavya-Manoharan Power Lindley (KMPL) distribution. We study the mathematical treatments of the KMPL distribution in detail and adapt the widely used method of maximum likelihood to estimate the unknown parameters of the KMPL distribution. We carry out a Monte carlo simulation study to investigate the performance of the Maximum Likelihood Estimates (MLEs) of the parameters of the KMPL distribution. To demonstrate the effectiveness of the KMPL distribution for data fitting, we use a real dataset comprising the waiting time of 100 bank customers. We compare the KMPL distribution with other models that are extensions of the power Lindley distribution. Based on some statistical model selection criteria, the summary results of the analysis were in favor of the KMPL distribution. We further investigate the density fit and probability-probability (p-p) plots to validate the superiority of the KMPL distribution over the competing distributions for fitting the waiting time dataset.

关键词： KM-Transformation Power Lindley Distribution Data Fitting Moments Quantiles

Predictors of survival in autoimmune liver disease overlap syndromes

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World Journal of Hepatology 2024年第9期16卷 1269-1277页

作者： Dujinthan Jayabalan Yi Huang Luis calzadilla-Bertot Malik Janjua Bastiaan de Boer John Joseph Wendy cheng simon Hazeldine Briohny W Smith Gerry c MacQuillan Michael c Wallace George Garas Leon A Adams Gary P Jeffrey Medical School University of Western AustraliaNed-lands 6009Western AustraliaAustralia Department of Hepatology Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia Department of Anatomical Pathology PathWest Laboratory MedicineNedlands 6009Western AustraliaAustralia Department of Gastroenterology and Hepatology Royal Perth HospitalPerth 6000Western AustraliaAustralia Department of Gastroenterology and Hepatology Fiona Stanley HospitalMurdoch 6150Western AustraliaAustralia Medical School University of Western AustraliaNedl-ands 6009Western AustraliaAustralia

BAcKGROUND Survival in patients with autoimmune liver disease overlap syndromes(AILDOS)compared to those with single autoimmune liver disease is *** To investigate the survival of patients with AILDOS and assess the accuracy of non-invasive serum models for predicting liver-related *** Patients with AILDOS were defined as either autoimmune hepatitis and primary biliary cholangitis overlap(AIH-PBc)or autoimmune hepatitis and primary sclerosing cholangitis overlap(AIH-PSc)and were identified from three tertiary centres for this cohort ***-related death or transplantation(liver-related mortality)was determined using a population-based data linkage *** scores for liver-related death were compared for accuracy[including liver outcome score(LOS),Hepascore,Mayo Score,model for end-stage liver disease(MELD)score and MELD incorporated with serum sodium(MELD-Na)score].RESULTS Twenty-two AILDOS patients were followed for a median of 3.1 years(range,0.35-7.7).Fourteen were female,the median age was 46.7 years(range,17.8 to 82.1)and median Hepascore was 1(range,0.07-1).At five years post enrolment,57%of patients remained free from liver-related mortality(74%AIH-PBc,27%AIH-PSc).There was no significant difference in survival between AIH-PBc and *** was a significant predictor of liver-related mortality(Pc(n=14)but not AIH-PSc(n=8).A LOS cut-point of 6 discriminated liver-related mortality in AIH-PBc patients(P=0.012,log-rank test,100%sensitivity,77.8%specificity)(Harrell's c-statistic 0.867).The MELD score,MELD-Na score and Mayo Score were not predictive of liver-related mortality in any *** Survival in the rare,AILDOS is *** current study supports the LOS as a predictor of liver-related mortality in AIH-PBc *** trials investigating predictors of survival in AILDOS are required.

关键词： Autoimmune liver disease overlap syndromes Liver outcome score Liver-related death Hepascore Autoimmune hepatitis Primary biliary cholangitis Primary sclerosing cholangitis

Rekindling *** cooperation

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Beijing Review 2024年第38期67卷 22-23页

作者： Denis simon The Institute for china-America Studies in Washington D.C

chinese President Xi Jinping's recent reply to a letter from Lamont Repollet,/President of Kean University in New Jersey,the U.S.,could not have occurred at a more opportune *** against the backdrop of the 50,000-student initiative announced by President Xi during a visit to the United States in November 2023,the letter emphasized the importance of educational exchanges in building positive bilateral relations,and called on universities in both countries to strengthen cooperation in pursuing ***.

关键词： U.S. letter universities

Evaluation of ruminal methane and ammonia formation and microbiota composition as affected by supplements based on mixtures of tannins and essential oils using Rusitec

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1607-1622页

作者： Giulia Foggi Melissa Terranova Matteo Daghio Sergej L.Amelchanka Giuseppe conte simon Ineichen Monica Agnolucci carlo Viti Alberto Mantino Arianna Buccioni Michael Kreuzer Marcello Mele Department of Agriculture Food and Environment(DAFE)University of Pisa56124 PisaItaly AgroVet‑Strickhof ETH ZurichLindauSwitzerland Department of Agriculture FoodEnvironment and ForestryUniversity of FlorenceFlorence 50144Italy centro Di Ricerche Agro‑Ambientali“E.Avanzi” University of PisaPisa 56122Italy School of Agricultural Forest and Food Sciences HAFLBern University of Applied SciencesZollikofenSwitzerland Institute of Agricultural Sciences ETH ZurichLindauSwitzerland

Background Dietary supplements based on tannin extracts or essential oil compounds(EOc)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous batch culture screening of various supplements identified selected mixtures with an enhanced potential to mitigate ruminal methane and ammonia *** these,Q-2(named after quebracho extract and EOc blend 2,composed of carvacrol,thymol,and eugenol)and c-10(chestnut extract and EOc blend 10,consisting of oregano and thyme essential oils and limonene)have been investigated in detail in the present study with the semi-continuous rumen simulation technique(Rusitec)in three independent *** this purpose,Q-2 and c-10,dosed according to the previous study,were compared with a non-supplemented diet(negative control,Nc)and with one supplemented with the commercial EOc-based Agolin^(R) Ruminant(positive control,Pc).Results From d 5 to 10 of fermentation incubation liquid was collected and analysed for pH,ammonia,protozoa count,and gas *** residues were collected for the determination of ruminal *** d 10,samples of incubation liquid were also characterised for bacterial,archaeal and fungal communities by high-throughput sequencing of 16S rRNA and 26S ribosomal large subunit gene *** of the duration of the fermentation period,Q-2 and c-10 were similarly efficient as Pc in mitigating either ammonia(-37%by Q-2,-34%by Pc)or methane formation(-12%by c-10,-12%by Pc).The Pc was also responsible for lower feed degradability and bacterial and fungal richness,whereas Q-2 and c-10 effects,particularly on microbiome diversities,were limited compared to *** All additives showed the potential to mitigate methane or ammonia formation,or both,in vitro over a period of 10 ***,several differences occurred between Pc and Q-2/c-10,indicating different mechanisms of *** pronounced defaunation caused by Pc a

关键词： Additive Bacteria continuous culture Degradability Fermentation Fungi Greenhouse gas In vitro Microbiome Rumen

A system-on-chip microwave photonic processor solves dynamic RF interference in real time with picosecond latency

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Light(Science & Applications) 2024年第1期13卷 91-102页

作者： Weipeng Zhang Joshua c.Lederman Thomas Ferreira de Lima Jiawei Zhang simon Bilodeau Leila Hudson Alexander Tait Bhavin J.Shastri Paul R.Prucnal Department of Electrical and computer Engineering Princeton UniversityPrinceton08544NJUSA NEc Laboratories America Princeton08540NJUSA Department of Electrical and computer Engineering Queen’s UniversityKingstonK7L 3N6OntarioCanada Department of Physics Engineering Physics and AstronomyQueen’s UniversityKingstonK7L 3N6OntarioCanada

Radio-frequency interference is a growing concern as wireless technology advances,with potentially life-threatening consequences like interference between radar altimeters and 5 G cellular *** transceivers mix signals with varying ratios over time,posing challenges for conventional digital signal processing(DSP)due to its high *** challenges will worsen as future wireless technologies adopt higher carrier frequencies and data ***,conventional DSPs,already on the brink of their clock frequency limit,are expected to offer only marginal speed *** paper introduces a photonic processor to address dynamic interference through blind source separation(BSS).Our system-on-chip processor employs a fully integrated photonic signal pathway in the analogue domain,enabling rapid demixing of received mixtures and recovering the signal-of-interest in under 15 *** reduction in latency surpasses electronic counterparts by more than three orders of *** complement the photonic processor,electronic peripherals based on field-programmable gate array(FPGA)assess the effectiveness of demixing and continuously update demixing weights at a rate of up to 305 *** compact setup features precise dithering weight control,impedance-controlled circuit board and optical fibre packaging,suitable for handheld and mobile *** experimentally demonstrate the processor’s ability to suppress transmission errors and maintain signal-to-noise ratios in two scenarios,radar altimeters and mobile *** work pioneers the real-time adaptability of integrated silicon photonics,enabling online learning and weight adjustments,and showcasing practical operational applications for photonic processing.

关键词： processor mixing dynamic

Analysis of the Quality of Physical and chemical Parameters of Groundwater in Three Localities in the Sub-Prefecture of Zanzra (Ivory coast)

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Journal of Materials Science and chemical Engineering 2024年第4期12卷 1-17页

作者： Djedjess Essoh Jules-césar Meledje Bi Irié Marc Gouli Drissa Ouattara Kra Vanh Eric.simon Zran Adjourma Konate Albert Trokourey Laboratoire de chimie des Eaux (LcE) de l’ Ecole Normale Sup&#233rieure d&#8217Abidjan Abidjan C&#244te d&#8217Ivoire Laboratoire de constitution et Ré action de la Mati&#232re (LCRM) &#224 l&#8217UFR SSMT-Universit&#233 F&#233lix Houphou&#235t-Boigny (UFHB) de Cocody Abidjan C&#244te d&#8217Ivoire

The availability of groundwater of acceptable quality has become a difficult challenge to meet in many countries, particularly côte d’Ivoire. The State of côte d’Ivoire and rural populations are building hydraulic infrastructure for this purpose. However, the quality of water coming from these infrastructures remains to be determined. This study therefore aims to analyze certain physicochemical parameters of the groundwater of Gloazra, Kouezra and Trahonfla. These are temperature, pH, electrical conductivity, TDS, salinity level, hardness, alkalinity, chloride content and bicarbonate. To determine the pH, electrical conductivity, temperature, TDS, and salinity rate, an electrochemical analysis was carried out. The titrimetric analysis made it possible to determine the chloride and bicarbonate content, alkalinity, and hardness. The results indicate that the studied groundwater is soft and acidic with good mineralization. This water does not present a health hazard to consumers but can affect hydraulic equipment and household containers.

关键词： Ivory coast Gloazra Trahonfla Kouezra Physicochemical Parameters Water WHO Standards

Photoelectrochemical Iron-catalyzed c(sp^(3))-H Borylation of Alkanes in a Position-Selective Manner

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ccS chemistry 2024年第6期6卷 1430-1438页

作者： Wen Wei Bin Wang simon L.Homölle Jinbin Zhu Yanjun Li Tristan von Münchow Isaac Maksso Lutz Ackermann Institut für Organische und Biomolekulare chemie Georg-August-Universität Göttingen37077 Göttingen

catalytic c-H borylation is of prime topical importance,since easily available feedstock chemicals can thereby be transformed into valuable transient functional groups in the absence of directing ***,we disclose an iron-catalyzed c(sp^(3))-H borylation of simple,non-prefunctionalized alkanes,providing access to value-added products in a single step by means of *** power of merging photo-and electrochemistry was mirrored by ample scope and exceedingly mild reaction ***,an outstanding position-selectivity in favor of primary c(sp^(3))-H proved viable within the photoelectrochemical borylation through a chemo-selective anodic overoxidation *** ferro-photoelectrochemistry strategy avoids toxic precious transition metals,enabling c(sp^(3))-H borylations in a site-selective fashion.

关键词： photoelectrocatalysis c(sp^(3))-H borylation iron catalysis position-selectivity chlorine radical