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Design and Experimental Testing of a Moving Coil Actuator with Compensation Coil

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 707-716页

作者： Boyuan Yin Xianwu Zeng John Frederick Eastham Emelie nilsson Jean-francois Rouquette Jean Rivenc Ludovic Ybanez Xiaoze Pei Department of Electronics&Electrical Engineering University of BathBathBA27AYUnited Kingdom Airbus UpNext BlangnacFrance Airbus CRT BlangnacFrance Department of Mechanical Engineering University of BathBathBA27AYUnited Kingdom

Hydrogen-powered electric aircraft have attracted significant interests aiming to achieve decarbonization *** DC electric networks are facing great challenges in DC fault protection *** interrupters are widely used in low voltage and medium voltage power systems due to being environmentally friendly with low *** this paper a moving coil actuator with compensation coils for a vacuum interrupter,as part of a hybrid direct current circuit breaker,is designed and experimentally *** coils are used to improve operating speed compared with original moving coil *** between four possible connections of compensation coils and original moving coil actuator are carried *** results show comparisons between different connections of actuator coils in terms of opening time and coil current with a range of pre-charged capacitor *** performance of each actuator connection is also *** actuator with compensation coils is shown to have a higher current rising rate and achieve faster opening speed,which is a critical requirement for electric aircraft network *** parallel connection actuator achieves the highest opening speed within 3.5 ms with capacitor voltage of 50 V.

关键词： Circuit breaker compensation coil moving coil actuator vacuum interrupter

Target blood pressure in diabetes patients with hypertension——What is the accumulated evidence in 2011?

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第8期12卷 611-623页

作者： Peter M.nilsson Department of Clinical Sciences Lund UniversityUniversity Hospital

There is overwhelming evidence that hypertension is an important risk factor for both macrovascular and microvascular complications in patients with diabetes,but the problem remains to identify appropriate goals for preventive therapies.A number of guidelines (the European Society of Cardiology (ESC)/European Association for the Study of Diabetes (EASD) 2007,the Joint National Committee (JNC)-Ⅶ 2003,the American Diabetes Association (ADA) 2011) have for example advocated a blood pressure goal of less than 130/80 mmHg,but this suggestion has been challenged by findings in recent trials and meta-analyses (2011).The European Society of Hypertension (ESH) therefore recommends a systolic blood pressure goal of "well below" 140 *** on evidence from both randomized controlled trials (hypertension optimal treatment (HOT),action in diabetes and vascular disease:preterax and diamicron MR controlled evaluation (ADVANCE),action to control cardiovascular risk in diabetes (ACCORD)) and observational studies (ongoing telmisartan alone and in combination with ramipril global endpoint trial (ONTARGET),international verapamil-trandolapril study (INVEST),treat to new targets (TNT),and the National Diabetes Register (NDR)),it has been shown that the benefit for stroke reduction remains even at lower achieved blood pressure levels,but the risk of coronary events may be uninfluenced or even increased at lower systolic blood pressure *** a recent meta-analysis,it was therefore concluded that the new recommended goal should be 130-135 mmHg systolic blood pressure for most patients with type 2 *** risk factors should also be controlled with a more ambitious strategy applied in the younger patients with shorter diabetes duration,but a more cautious approach in the elderly and frail patients with a number of vascular or non-vascular *** patients from East Asia,such as China,the stroke risk is relatively higher than the risk of coronary *** must al

关键词： Blood pressure Cardiovascular Diabetes Goal Hypertension Treatment

Static/dynamic friction and wear of some selected polymeric materials for conformal tribo-pairs under boundary lubrication conditions

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Friction 2013年第3期1卷 232-241页

作者： Daniel nilsson Braham PRAKASH Bosch Rexroth Mellansel AB MellanselSweden Division of Machine Elements Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleåSweden

This work is aimed at investigating the friction and wear performance of different polymeric materials having potential for hydraulic system components under lubricated sliding conditions against a steel counter face.A pin-on-disc test configuration was used for the experimental *** different polymeric materials selected for these studies were commercial polyimides(PI),polyether ether ketone(PEEK),and *** of these materials were bulk materials whereas others were used as coatings applied on to the cast iron *** tribological characteristics of the polymers were compared with a reference grey cast *** frictional characteristics were evaluated in both static and dynamic *** results have shown that by using polymeric materials it is possible to reduce breakaway friction by an order of magnitude compared to grey cast ***,the breakaway friction increased significantly after the wear *** polymeric materials having lowest breakaway friction have shown the highest wear with the exception of the PEEK-PTFE coating which showed low *** with graphite fillers also showed low wear but it resulted in relatively high *** carbon fibre reinforced materials resulted in unstable friction as well as higher wear compared to the PI materials with graphite fillers.

关键词： polymer tribology static friction dynamic friction and lubricated wear

Are flight paths of nocturnal songbird migrants influenced by local coastlines at a peninsula？

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Current Zoology 2014年第5期60卷 660-669页

作者： Cecilia nilsson Johan BACKMAN Thomas ALERSTAM Department of Biology Lund University SE-223 62 Lund Sweden

By recording nocturnally migrating passerines with tracking radar we have investigated how coastlines affect the migrants＇ flight paths. Birds could use coastlines as an orientation aid or as a reference cue to compensate for wind drift while mi- grating. However, on the small scale of Falsterbo Peninsula in southern Sweden, we found very little effect of coastlines on migrants flight paths, irrespective of altitude. We tracked 2 930 migrants in three autumn and two spring seasons, at altitudes from 60 up to 3 000 meters. We compared tracks of migrants flying in three different areas, which correspond to the three main coastlines, and can demonstrate that the orientation of the tracks did not differ in a way consistent with the coastlines between the areas in autumn, and showed only a slight effect in spring. This is in accordance with earlier infrared device monitoring in Falsterbo, but contrary to earlier visual observations. It supports the view of nocturnally migrating passerines as mainly broad-front migrants. Even though the coastlines on the scale of the peninsula affected the flight paths very little, it is possible that the coastline has an effect on a larger regional scale, by migrants avoiding long sea crossings and thereby being funneled towards the peninsula, but this remains to be investigated [Current Zoology 60 （5）： 660-669, 2014].

关键词： Bird migration Passerines Coastlines Leading lines Flight paths

Why People Live in Flood-Prone Areas in Akuressa, Sri Lanka

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International Journal of Disaster Risk Science 2018年第2期9卷 143-156页

作者： Johan Askman Olof nilsson Per Becker Division of Risk Management and Societal safety Lund University

To investigate why people live in areas at high risk of floods, a qualitative case study was carried out in the areas around Akuressa, in southwest Sri Lanka. Data collection consisted mainly of semistructured interviews with local residents and government officials. The purpose was to study why people live in areas at high risk of floods, by looking beyond the purely physical aspects of living with hazards and exploring the underlying social factors. Four main factors were identified: an overall good living situation; a sense of place; difficulties relocating; and being well-adapted to the situation. The analysis also examined whether government officials shared the views of local residents. The findings highlighted both areas of consensus and discrepancies related to risk awareness, and the efficiency of risk reduction measures that had been implemented by the government. The case study identified and explored underlying social factors, such as risk normalization, risk trade-offs, and push-and-pull processes, which seem to influence the decision to live in a high-risk area.

关键词： Flood risk Risk awareness Risk perception Sri Lanka

Epigenetics and transgenerational inheritance in domesticated farm animals

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Journal of Animal Science and Biotechnology 2015年第2期6卷 123-129页

作者： Amanda Feeney Eric nilsson Michael K Skinner Center for Reproductive Biology School of Biological Sciences Washington State University

Epigenetics provides a molecular mechanism of inheritance that is not solely dependent on DNA sequence and that can account for non-Mendelian inheritance patterns. Epigenetic changes underlie many normal developmental processes, and can lead to disease development as well. While epigenetic effects have been studied in well-characterized rodent models, less research has been done using agriculturally important domestic animal species. This review will present the results of current epigenetic research using farm animal models （cattle, pigs, sheep and chickens）. Much of the work has focused on the epigenetic effects that environmental exposures to toxicants, nutrients and infectious agents has on either the exposed animals themselves or on their direct offspring. Only one porcine study examined epigenetic transgenerational effects; namely the effect diet micronutrients fed to male pigs has on liver DNA methylation and muscle mass in grand-offspring （F2 generation）. Healthy viable offspring are very important in the farm and husbandry industry and epigenetic differences can be associated with production traits. Therefore further epigenetic research into domestic animal health and how exposure to toxicants or nutritional changes affects future generations is imperative.

关键词： Environment EDiclenetics Pig. Review Transgenerational

Characterizing gastrointestinal stromal tumors and evaluating neoadjuvant imatinib by sequencing of endoscopic ultrasound-biopsies

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World Journal of Gastroenterology 2017年第32期23卷 5925-5935页

作者： Per Hedenstrom Bengt nilsson Akif Demir Carola Andersson Fredrik Enlund Ola nilsson Riadh sadik Division of Medical Gastro-enterology Department of Internal MedicineSahlgrenska University Hospital Department of Surgery Sahlgrenska University Hospital Department of Clinical Pathology and Genetics Sahlgrenska University Hospital

AIM To evaluate endoscopic ultrasound(EUS)-guided biopsies for the pretreatment characterization of gastrointestinal stromal tumors(GIST) to personalize the management of *** All patients with lesions suspected to be GIST who were referred for EUS-sampling at a tertiary Swedish center were eligible for inclusion 2006-2015. During the observational study phase(2006-2011), routine fine-needle-aspiration(EUS-FNA) was *** 2012-2015, we converted to an interventional, randomized protocol with dual sampling EUS-FNA and fine-needle-biopsy-sampling(EUS-FNB) for all lesions. c-KIT-and DOG-1-immunostaining was attempted in all samples and a manual count of the Ki-67-index was performed. FNB-sampled tissue and the resected specimens were subjected to sanger sequencing of the KIT and platelet-derived growth factor alpha(PDGFRA) genes. RESULTS In all, 64 unique patients with GIST were included, and of these, 38 were subjected to pretreatment dual sampling. EUS-FNB had a higher diagnostic sensitivity when compared head-to-head with EUS-FNA(98% vs 58%, P sampling is accurate for the pretreatment diagnosis and characterization of GISTs and allows the prediction and evaluation of tumor response to neoadjuvant imatini

关键词： Endosonography Fine-needle biopsy Gastrointestinal stromal tumor KIT Platelet-derived growth factor alpha Tumor proliferation rate Ki-67 index Neoadjuvant treatment Imatinib

Non-alcoholic fatty liver disease-a chronic disease of the 21^(st) century

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The Journal of Biomedical Research 2018年第5期32卷 327-335页

作者： Peter Metrakos Tommy nilsson Cancer Research Program Block-E The Research Institute of the McGill University Health Centre and Department of Medicine McGill University

Non-alcoholic fatty liver disease（NAFLD） comprises a spectrum of metabolic states ranging from simple steatosis to inflammation with associated fibrosis to cirrhosis. Though accumulation of hepatic fat is not associated with a significant increase in mortality rates, hepatic inflammation is, as this augments the risk of terminal liver disease, i.e.,cirrhosis, hepatic decompensation（liver failure） and/or hepatocellular carcinoma. Disease progression is usually slow, over a decade or more and, for the most part, remains asymptomatic. Recent estimates suggest that the global prevalence of NAFLD is high, about one in four. In most cases, NAFLD overlaps with overweight, obesity,cardiovascular disease and the metabolic syndrome with numerous contributing parameters including a dysregulation of adipose tissue, insulin resistance, type 2 diabetes, changes in the gut microbiome, neuronal and hormonal dysregulation and metabolic stress. NAFLD is diagnosed incidentally, despite its high prevalence. Non-invasive imaging techniques have emerged, making it possible to determine degree of steatosis as well asfibrosis. Despite this,the benefit of routine diagnostics remains uncertain. A better understanding of the（molecular） pathogenesis of NAFLD is needed combined with long-term studies where benefits of treatment can be assessed to determine costbenefit ratios. This review summarizes the current state of knowledge and possible areas of treatment.

关键词： non-alcoholic fatty liver disease pathogenesis molecular mechanism diagnostics biomarker

Remote estimation of the fraction of absorbed photosynthetically active radiation for a maize canopy in Northeast China

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Journal of Plant Ecology 2015年第4期8卷 429-435页

作者： Feng Zhang Guangsheng Zhou Christer nilsson State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences20 NanxincunXiangshanHaidian DistrictBeijing 100093China Chinese Academy of Meteorological Sciences 46 Zhongguancun South StreetHaidian DistrictBeijing 100081China Landscape Ecology Group Department of Ecology and Environmental ScienceUmeåUniversityUmeåSE-90187Sweden

Aims accurate remote estimation of the fraction of absorbed photosynthetically active radiation(fAPAR)is essential for the light use efficiency(LUE)***,one challenge for the LUE models is lack of knowledge about the relationship between fAPAR and the normalized difference vegetation index(NDVI).Few studies have tested this relationship against field measurements and evaluated the accuracy of the remote estimation *** study aimed to reveal the empirical relationship between NDVI and fAPAR and to improve algorithms for remote estimation of *** to investigate the method of remote estimation of fAPAR seasonal dynamics,the CAsa(Carnegie-ames-stanford approach)model and spectral vegetation indices(VIs)were used for in situ measure-ments of spectral reflectance and fAPAR during the growing season of a maize canopy in Northeast *** Findingsthe results showed that the fAPAR increased rapidly with the day of year during the vegetative stage,it remained relatively stable at the stage of reproduction,and finally decreased slowly during the senescence *** addition,fAPAR green[fAPAR_(green)=fAPAR_(green) -fAPAR_(green) LAI_(max))]showed clearer seasonal trends than *** NDVI,red-edge NDVI,wide dynamic range vegetation index,red-edge position(REP)and REP with sentinel-2 bands derived from hyperspectral remote sensing data were all significantly positively related to fAPAR green during the entire growing *** a comparison of the predictive performance of VIs for the whole growing season,REP was the most appropriate spectral index,and can be recommended for monitoring seasonal dynamics of fAPAR in a maize canopy.

关键词： fraction of absorbed photosynthetically active radiation hyperspectral remote sensing maize canopy spectral vegetation indices