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Fault diagnosis of railway point machines based on wavelet transform and artificial immune algorithm

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Transportation Safety and Environment 2023年第4期5卷 117-126页

作者： Xiaochun Wu weikang yang Jianrong Cao School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070GansuChina China Railway Rolling Stock Corporation Qingdao Sifang Rolling Stock Research Institute Co. LtdQingdao 266000ShandongChina

Aiming at the current problems of high failure rate and low diagnostic efficiency of railway point machines(RPMs)in the railway industry,a short-time method of fault diagnosis is *** the effect of noise on power signals in the data acquisition process of the railway centralized signaling monitoring(CSM)system,this study utilizes wavelet threshold denoising to eliminate *** results show that the accuracy of fault diagnosis can be improved by 4.4% after denoising the power *** in order to attain a lighter weight and shorten the running time of the diagnosis model,Mallat wavelet decomposition and artificial immune algorithm are applied to RPM fault ***,voluminous experiments using veritable power signals collected from CSM are introduced,which show that combining these methods can procure higher precision of RPMs and curtail fault diagnosis *** substantiates the validity and feasibility of the presented approach.

关键词： railway point machines wavelet threshold denoising Mallat wavelet decomposition artificial immune algorithm

Diet characteristics of wild sheep(Ovis ammon darwini) in the Mengluoke Mountains,Xinjiang,China

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Journal of Arid Land 2018年第3期10卷 482-491页

作者： LI Bang XU Wenxuan David A BLANK WANG Muyang yang weikang Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Research Center for Ecology and Environment of Central Asia Bishkek 720001 Kyrgyzstan

In most arid and semi-arid regions of the world, domestic livestock and native wildlife share pastures, and their competition for forage and habitat is thought to be a serious conservation issue. Moreover, unmanaged grazing by livestock can cause the population decline in wild ungulates. The diet of an animal species is a determining aspect of its ecological niche, and investigating its diet has been one of the initial steps in basic ecology study of a new species. To get an approximate understanding of the interspecific food relationships of argali（Ovis ammon darwini） between sexes, and sympatric domestic sheep and goats, we compared the diet compositions and diet-overlaps among these herbivores, i.e., male argali, female argali, domestic sheep, and domestic goats in the Mengluoke Mountains of Xinjiang, China by using micro-histological fecal analysis. Female argali, male argali, domestic sheep and domestic goat primarily consumed forbs（43.31%±4.86%）, grass（36.02%±9.32%）, forbs（41.01%±9.18%）, and forbs（36.22%±10.61%）, respectively in warm season. All these animals consumed mostly shrubs（female argali： 36.47%±7.56%; male argali： 47.28%±10.75%; domestic sheep： 40.46%±9.56%; and domestic goats： 42.88%±9.34%, respectively） in cold season. The diet-overlaps were relatively high among all species in cold season with values ranging from 0.88 to 0.94. Furthermore, Schoener＇s index measured between each possible pair of 4 herbivores increased from the warm season to the cold season. The results illustrate that the high degree of diet-overlap of argali and domestic livestock（sheep and goat） may pose a threat to the survival of the argali in cold season. From the viewpoint of rangeland management and conservation of the endangered argali, the numbers of domestic sheep and goats should be limited in cold season to reduce food competition.

关键词： argali fecal analysis food habits competition diet-overlap

Impact of great gerbils(Rhombomys opimus) on desert plant communities

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Journal of Arid Land 2015年第6期7卷 852-859页

作者： XU Wenxuan LIU Wei yang weikang WANG Muyang XU Feng David BLANK Key laboratory of Biogeography and Bioresources in Arid Lands Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences College of Life Science and Technology Southwest University for Nationalities

Great gerbil（Rhombomys opimus） colonies, with bare soil and herbaceous plants, are conspicuous to the background environment throughout their range area. In order to quantify the engineer role of great gerbils, we investigated the plant communities of 20 active colonies in the Junggar Basin, Xinjiang, China. In areas without disturbance, desert plant communities were dominated by the shrubs with low level species richness. In burrow areas and surrounding intermediate areas, which were disturbed by great gerbils, the shrubs were suppressed with the decrease of vegetation cover and aboveground biomass. As a result, ＂niche gaps＂ were created in disturbed areas and worked as a refuge for herbaceous annuals and perennials. So the existence of great gerbils increased the overall species richness of the desert. Furthermore, herbaceous annuals and perennials are the major food source for great gerbils in spring, indicating that great gerbils have a mutually beneficial relationship with herbaceous plants.

关键词： Rhombomys opimus ecosystem engineer species richness mutually beneficial relationship

Distribution and status of bustards in China

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Frontiers in Biology 2008年第4期3卷 385-391页

作者： Xingyi GAO weikang yang Jianfang QIAO Jun YAO Kefen XU Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

This article presents the distribution and status of bustards,which are listed as first-category protected animals according to the survey results during 1990–2002 in *** Chinese populations of Otis tarda dybowskii are breeding in south-west of Heilongjiang Province,western Jilin Province,east and middle Inner Mongolia,north Ningxia Hui Autonomous Region,and Gansu Province.A few can winter in the south *** winterrange lies from the south to the Yellow River,as far as to Guizhou Province and Jiangxi *** population number is about 200–300 or 500–*** Chinese populations of *** are breeding in the north and west of *** is unclear about its winter-range,which is presumed to be in south *** we found individuals wintering in Chabuchaer and west *** population number is about 2000–*** habitat in breeding range includes steppe,grassland,desert grassland,and *** habitat in winter range is the beach of rivers and lakes,meadows,meadow-grassland,and *** Chinese populations of Chlamydotis undulata macqueeni are breeding in the fringe of the Jungar Basin,the banks of the Ulungur River,Balikun and south Turpan Basin in Xinjiang,west Inner Mongolia,and west *** Mulei in eastern Jungar Basin of Xinjiang is the main breeding-range in the *** bird uses desert and desert grassland as its *** winter-range is west Asia and south *** population number is about *** Chinese populations of Tetrax tetrax are breeding in north Xinjiang,and China is located on the east border of its *** habitat is grassland and semi-desert,and its winter-range lies in south *** population in China is very *** addition,we analyzed the causes of their endangerment and put forward protection tactics of Chinese Bustards.

关键词： Great Bustard(Otis tarda) Houbara Bustard(Chlamydotis undulata) Little Bustard(Tetrax tetrax) distribution status

Selecting flagship species to solve a biodiversity conservation conundrum

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Plant Diversity 2020年第6期42卷 488-491页

作者： Jie Qian Huifu Zhuang weikang yang Yifeng Chen Shilong Chen Yanhua Qu Yuanming Zhang Yongping yang Yuhua Wang Kunming Institute of Botany Chinese Academy of Sciences132 Lanhei RoadKunming650201YunnanChina Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences818 South Beijing RoadUrumqi830011XinjiangChina Northwest Institute of Plateau Biology Chinese Academy of Sciences23 Xinning RoadXining810008QinghaiChina Institute of Hydrobiology Chinese Academy of Sciences7 Donghu South RoadWuhan430072HubeiChina Institute of Zoology Chinese Academy of Sciences1 Beichen West RoadChaoyang DistrictBeijing100101China

The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum.A project of the Chinese Academy of Sciences has concluded that progress can be made through the use of flagship species selected using criteria drawn from conservation biology,ecosystem function,socio-economics,and cultural *** of the latter three criteria will help attract and maintain the commitment of the public to play full parts in carrying out any conservation measures needed.A system is proposed for scoring species to select those that are most suitable as *** method can be used regardless of the size of the area chosen for attention,whether it is a region,a country,or a particular protected area.

关键词： Flagship species Selection criteria Biodiversity conservation Proposed program

Status and distribution of ungulates in Xinjiang,China

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Journal of Arid Land 2011年第1期3卷 49-60页

作者： XingYi GAO WenXuan XU weikang yang David A BLANK JianFang QIAO KeFen XU Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Acad- emy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Zoology Kazakhstan Academy of Sciences Almaty 050010 Kazakhstan

Based on a long-term field investigation and other research results, we reviewed the status and distribution of ungulates in Xinjiang, China. The ungulates in Xinjiang included 19 ungulate species （30 subspecies） from 6 families and 2 orders. Among them, 3 species （2 subspecies） relate to Equidae （Per- risodactyla）, and 16 species （28 subspecies） are from 5 families of Artiodactyla. In this paper, we analyzed the conservation status of most rare and important 13 ungulate species. Firstly, we proposed the protec- tion of genetic diversity of Camelus ferus and the distribution areas of Moschus sifanicus, Procapra przewalskii and Saiga tatarica in Xinjiang. We found that Moschus sifanicus but not Procapra przewalskii distributed in Xinjiang. It was not clear whether the remnant populations of Saiga tatarica existed in Xinjiang and China-Kazakhstan border or not. We discussed that the protection level and rational use of Capra si- birica and enhancing protection level and enlarging monitoring and research projects for Pantholops hodgsoni and Gazella subgutturosa. And we would like to suggest Forestry Department to develop the captive breeding of Tibetan antelope for rational use. In addition, the captive breeding of Cervus elaphus in Xinjiang was reviewed. Local government should lessen strong control to Cervus elaphus because of many breeding centers＇ establishment.

关键词： Xinjiang of China ungulate species and distribution status

Characterization of a new 4,6-α-glucanotransferase from Limosilactobacillus fermentum NCC 3057 with ability of synthesizing low molecular mass isomalto-/maltopolysaccharide

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Food Bioscience 2022年第2期46卷 241-250页

作者： weikang yang Lufei Sheng Sheng Chen Lei Wang Lingqia Su Jing Wu State Key Laboratory of Food Science and Technology Jiangnan University1800 Lihu AvenueWuxi214122China School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education Jiangnan University1800 Lihu AvenueWuxi214122China International Joint Laboratory on Food Safety Jiangnan University1800 Lihu AvenueWuxi214122China

4,6-α-Glucanotransferase(4,6-α-GT)converts starch into product with increasedα(1-6)glycosidic bonds ratio,and this product is a new type of soluble dietary fiber with property of escaping small intestine digestion.4,6-α-GT gained interest recently because of their potential use in enzymatic synthesis of soluble dietary *** this study,a putative GtfB sequence from Limosilactobacillus fermentum NCC 3057 was *** sequence was truncated and expressed in Escherichia coli to obtain the protein *** NCC 3057 GtfBΔ***ΔN showed optimal activity at 35℃and pH 6.0,and it converted amylose V to isomalto-/maltopolysaccharide(IMMP)with low molecular mass(3.1 kDa).This IMMP product contains 72%α(1-6)glycosidic bonds,and it showed 64%indigestible content in vitro digestion *** results indicate that the product of *** NCC 3057 GtfBΔN is a soluble dietary *** the X-ray crystal structure of GtfBΔN(2.4Å)was *** on the GtfBΔN structure,we offer an insight about that three loops of domain C may be related to the molecular mass of IMMP product.

关键词： 4,6-α-Glucanotransferase Isomalto-/maltopolysaccharide Soluble dietary fiber X-ray crystal structure Molecular mass of product NMR spectroscopy

Winter habitat use of snow leopards in Tomur National Nature Reserve of Xinjiang,Northwest China

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Journal of Arid Land 2012年第2期4卷 191-195页

作者： Feng XU Ming MA weikang yang David BLANK YiQun WU Thomas MCCARTHY Bariusha MUNKHTSOG Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Department of Environment and Life Sciences Weinan Teachers University Weinan 714000 China International Snow Leopard Trust Seattle WA 98103 USA Institute of Biology Mongolian Academy of Sciences Ulaanbaatar 51 BZD Mongolia

Snow leopards are one of the least known large cats, the population of which has dramatically de- creased. Their habitat loss was considered the main reason for the decline during the last decade, but their habitat preferences are still not well known. In this paper, we studied the winter habitat preferences of snow leopards in the Tomur National Nature Reserve （TNNR） in Northwest China during 2004-2005. We used sign surveys and tran- sects to study the winter habitat selection of snow leopards. The results indicated that snow leopards showed a preference for habitat variabilities in slope aspect, vegetation cover, dominant topographical features, landform ruggedness and grazing status. We found that prey availability and dominant topographical features were the most important factors that determined the winter habitat selection of snow leopards. Our results supported the idea that the habitat preferences of snow leopards are a tradeoff between suitable habitat features and avoidance of potential human interactions.

关键词： snow leopard Panthera uncia sign survey habitat preferences Tomur National Nature Reserve

The cluster digging behavior of larvae confers trophic benefits to fitness in insects

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Insect Science 2024年第3期31卷 870-884页

作者： Yujie Wu Qiang Wang weikang yang Sheng Zhang Chuan-Xi Mao Nana He Shaojie Zhou Chuanming Zhou Wei Liu School of Plant Protection Anhui Agricultural UniversityAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Province Engineering Laboratory for Green Pesticide Development and ApplicationHefeiChina College of Plant Protection Nanjing Agricultural UniversityNanjingChina School of Teacher Education Nanjng Xiaozhuang UniversityNanjingChina State Key Laboratory of Biocatalysis and Enzyme Engineering Hubei Province Key Laboratory of Biotechnology of Chinese Traditional MedicineNational&Local Joint Engineering Research Center of High-throughput Drug Screening TechnologySchool of Life ScienceHubei UniversityWuhanChina

Collective behaviors efficiently impart benefits to a diversity of species ranging from bacteria to *** larvae tend to cluster and form coordinated digging groups under crowded conditions,yet understanding the rules governing this behavior is in its *** primarily took advantage of the Drosophila model to investigate cooperative foraging ***,we report that Drosophila-related species and the black soldier fly have evolved a conserved strategy of cluster digging in food ***,we investigated relative factors,including larval stage,population density,and food stiffness and quality,that affect the cluster digging ***,oxygen supply through the posterior breathing spiracles is necessary for the organization of digging *** importantly,we theoretically devise a mathematical model to accurately calculate how the cluster digging behavior expands food resources by diving depth,cross-section area,and food *** found that cluster digging behavior approximately increases 2.2 fold depth,1.7-fold cross-section area,and 1.9 fold volume than control groups,*** of food sources significantly facilitates survival,larval development,and reproductive success of Drosophila challenged with competition for limited food resources,thereby conferring trophic benefits to fitness in ***,our findings highlight that the cluster digging behavior is a pivotal behavior for their adaptation to food scarcity,advancing a better understanding of how this cooperative behavior confers fitness benefits in the animal kingdom.

关键词： cluster digging determinant development fecundity larvae mathematical model